Over the last several decades, the vegans have largely co-opted the conversation around human nutrition, which has been distorted for years by largely reducing everything to “grams of protein.” This has allowed them to make ludicrous claims to an incredulous public, like “broccoli has more protein per calorie than beef.“
Vegan Showdown: Broccoli vs. Beef
A) the claim is demonstrably false on its face, and
B) Let’s look closer and see what we actually get for 100 calories of broccoli vs 100 calories of beef sirloin (particularly when it comes to amino acids): *source: all values from cronometer
Broccoli
Beef
Oops. Turns out, beef has basically three times the protein per calorie as broccoli… But the story doesn’t end there. Let’s look at the micronutrient breakdown of both per 100 calories.
Amino Acid Content
Clearly, beef wins hands down in the battle of amino acids, particularly when it comes to leucine. (We’ll get more into why that matters later…)
Vitamins
Broccoli wins the contest for vitamin C and, on paper, vitamin K; however, the K in broccoli is not the active, animal-form K2. A theme we will revisit. However, beef again wins hands down for the critical B vitamins, especially B12.
Minerals
When it comes to minerals, broccoli seems to go head-to-head with beef, but once again, the iron in broccoli is non-heme, which is not the active animal form of iron, and beef blows broccoli out of the water when it comes to zinc, which is critical for hormonal health.
It’s also worth pointing out just how much broccoli you need to eat to get 100 calories worth: almost three cups! Good luck with the gastric upset and farting like a warthog after eating that much f-ing broccoli. Compare that to a less-than-normal portion of beef at a meager 62.5g to get 100 calories.
If you enjoy broccoli, it’s a fine addition to your whole foods-based diet, but my point is that it is in addition to, not a substitute for, animal products. I’m only picking on broccoli as an example. Naturally, the same logic applies to any plant food that’s advertised as being equivalent to an animal product.
Universally, they are not.
Micronutrient Density & Amino Acids
The more honest question is actually about micronutrient density, amino acid balance, amino acid ratios, digestibility, and whether a diet is truly aligned with human biology. Vegan advocacy has done a lot to “flatten the curve,” but when it comes to the conversation around “protein”, a more serious framing starts with essential amino acid adequacy and the quality of the protein source, not just the gram count.
Ancestral Health – The Dao of Human Nutrition
That is why ancestral health arguments have always been the strongest: humans are omnivores, yes, but omnivory does not mean all food sources are nutritionally equivalent.
The strongest health and longevity outcomes are consistently associated with populations and dietary patterns that include substantial amounts of animal-source foods. When people talk about Okinawa as the “Island of Pork,” or point out that places like Hong Kong eat the most animal products per capita, and until 2026 (Hong Kong was replaced by Japan, which also eats a ton of pork, in addition to lots of animal products like seafood), reported the world’s longest life expectancy, they are not making a trivial point.
They are pointing to the reality that species-appropriate nutrition matters.
This is also where the discussion gets more technical. Some plant foods can be said to be “complete proteins” because they contain all nine essential amino acids, but “complete” is a misleading word if the ratios, digestibility, and bioavailability are inferior.
Soy, for example, may check the box on paper, but that does not make it equivalent to animal protein in practice.
Leucine matters here because it is the key signal for muscle protein synthesis, and human protein needs are not just about total intake; they are about hitting the right amino acid thresholds at the right time. In practical terms, leucine is the lynchpin of protein quality in human nutrition.
And protein quality goes beyond amino acids alone. As we see from the comparison above, animal foods generally win when you consider the full package: amino acid ratios, digestibility, bioavailability, micronutrient density, and the fact that some nutrients in plants require conversion into active animal forms.
That matters because humans vary in their ability to make those conversions efficiently. Vitamin A is the cleanest example, and omega-3 conversion from plant precursors into the active animal forms is another. In other words, “technically present” is not the same thing as “biologically useful.”
The Bee Study – Species Specific Diets Matter
I want to shift to a study on honeybees because it illustrates a principle that matters far beyond insects: nutrition is not just about eating enough food; it is also fundamentally about matching the organism’s specific amino acid needs. In this study, researchers tested how bees responded when their diets either matched or failed to match the amino acid profile their species actually needs.
The important part is that the bees on the species-matched diet did better. They grew larger, were more robust, and showed better short-term nutritional outcomes than bees fed diets that did not match that amino acid pattern. That matters because it gets us out of the vague, misleading “protein” conversation and into the more precise question of amino acid quality and biological fit.
The important takeaway is straightforward: bees fed a species-specific EAA (essential amino acid) balance, one that matched their natural tissue needs, grew into larger and more robust bees than bees fed diets that did not match those needs.
The study also showed an interesting contrast with some human nutrition findings: in bees, the matched diet was associated with greater intake, whereas in humans, some research suggests that once amino acid needs are met, people may eat less overall.
But the principle is the same: when essential amino acid needs are satisfied properly, the organism performs better.
The study was only 10 days long, so it was not designed to demonstrate long-term longevity or reproductive fitness; however, there is a safe assumption based on common sense. Yes, “more study” is always warranted, and even welcome, but it doesn’t take a rocket scientist to understand that within the same species, a larger bee is a stronger, more robust bee, less prone to predation from other insects, and generally more resilient.
Mo’ Protein Is Mo’ Betta
That same logic shows up in human populations, too. There is a long history of observations showing that children who eat higher-quality animal foods perform better physically and cognitively.
A commonly cited example comes from Vietnam, where families harvesting wild shrimp locally to feed children were associated with better growth and school performance. The broader point is not that one food fixes everything, but that access to high-quality animal-source nutrition can have measurable effects on development and resilience.
Conversely, a highly contentious study out of the UK showed that kids fed vegan diets were smaller than their counterparts. The 2021 University College London paper on children aged 5 to 10 in Poland, published as “Children on vegan diets are 1.2 inches shorter on average, with smaller and weaker bones, study finds.” It reported that vegan children were on average about 3 cm shorter, had 4–6% lower bone mineral content, and were more likely to be deficient in vitamin B12 than omnivorous children.
The debate should not be reduced to “grams of protein.” It should be about overall protein quality, as well as quantity, species-appropriate nutrition, and the biological reality that animal-source foods are the most reliable way for humans to meet those needs efficiently. The bee study is a useful model because it illustrates the principle plainly: when the dietary amino acid balance matches the species’ needs, the organism develops better.
Ashe is a highly skilled martial arts instructor and certified nutrition coach with over two decades of experience in the field. He holds a Master Instructor certification in I Liq Chuan under Sam FS Chin, making him one of only several individuals worldwide to hold the title. He has taught classes and workshops worldwide and is passionate about helping others achieve their fitness and wellness goals.
With a background in full-contact fighting and a Level 2 certification from Precision Nutrition in nutrition coaching, Ashe is a well-rounded expert in the fields of martial arts. In addition to his expertise, he has a wealth of experience in teaching and mentoring others. He has a natural ability to connect with his students and inspire them to reach their full potential.
I am not a doctor or a lawyer, and the information provided should not be considered medical or legal advice.
The information provided is for educational and informational purposes only and should not be used as a substitute for professional legal or medical advice, diagnosis, or treatment. Consult your doctor or a qualified healthcare professional before making any changes to your diet, exercise routine, or lifestyle.
Please note that some of the links provided in this content may be affiliate links, meaning that I may receive a small commission if you purchase through them. However, please rest assured that any products or services recommended are based on my personal experience and belief in their value. I only recommend products or services that I have personally used and believe in.
When you picture the ancient Vikings, you see it instantly: muscular, bare-chested warriors rowing longships through the frigid North Sea, ice forming in their beards, or crashing shields together in snow-covered fields as if the cold were nothing more than background noise.
They weren’t just tough. They were resilient in a way that borders on myth—seemingly impervious to the freezing arctic winds that would cripple a modern desk-bound mortal.
But here’s the real question: Did these warriors possess a metabolic advantage we’ve forgotten?
These were people whose diets were dominated by cold-water fish—herring, salmon, mackerel, sardines—foods packed with omega-3s that modern science now shows can supercharge the body’s cold-adaptation machinery.
Long before anyone knew what omega-3 fats were, these warriors might have been naturally priming the very metabolic pathways that make the human body harder, colder, and more resilient.
A primeval “metabolic hack,” hidden in plain sight.
Fit To Fight: How Cold Exposure Turns Brown Fat Into a Glucose-Burning Furnace Understanding the 12-LOX → 12-HEPE Pathway and Why It Matters for Metabolic Health
Cold exposure isn’t just a test of toughness. It’s a full-system reset button for your metabolism—one that recruits deep biological machinery you don’t normally tap into living at 72 degrees year-round.
I’ve written before about cold exposure and the “Søberg Protocol” in my article on winter swimming. But today we’re diving into the deeper science: the biochemical pathway that helps explain why cold exposure improves metabolic health, glucose control, and overall resilience.
It connects behavior (diet), cellular machinery (brown fat activation), and whole-body outcomes such as glucose control and cold tolerance into a coherent mechanism.
Brown Fat: Your Built-In Heat Engine
Brown adipose tissue (BAT) is “metabolically active fat”—packed with mitochondria and designed to burn fuel for heat. Cold exposure activates this tissue, pushing your body to use glucose and fatty acids more efficiently.
Brown Fat activity during cold exposure and room temperature Source: unknown
But activation is only part of the story.
Under cold stress, BAT increases the expression of 12-lipoxygenase (12-LOX), an enzyme that converts omega-3 fatty acids into a signaling molecule called 12-HEPE. Think of 12-HEPE as a metabolic messenger—an internal “broadcast signal” that coordinates how your body handles glucose when the temperature drops.
When cold or adrenergic stimulation hits:
12-LOX activity rises
12-HEPE production spikes
These lipids enter the bloodstream
And your entire metabolism shifts into a higher-performance mode
BAT isn’t just warming you—it’s giving orders.
Cold Exposure Boosts 12-HEPE in Both Mice and Humans
Across multiple models—mice, cultured cells, and human volunteers—the pattern is the same:
Cold exposure rapidly increases circulating 12-HEPE—within about an hour.
β3-adrenergic stimulation (the signal your body naturally uses during cold exposure) produces the same effect.
Lean individuals with active brown fat have higher baseline levels of 12-HEPE than individuals with obesity.
This pathway is not subtle. It switches on fast and hard.
Enhances glucose uptake in brown fat, white fat, and skeletal muscle
Activates a Gs-coupled receptor, triggering an insulin-like signaling cascade
Increases GLUT4 translocation, pulling glucose into tissues more effectively
Improves systemic glucose tolerance
Upregulates genes involved in glucose metabolism
Enhances cold-induced thermogenesis
This means 12-HEPE makes your metabolism more flexible—better at using fuel, better at managing blood sugar, better at handling cold.
This is the biology behind cold resilience.
What Happens When 12-LOX Is Missing?
Mouse models with 12-LOX deleted in brown fat demonstrate exactly how crucial this pathway is:
Their brown fat can’t take up glucose efficiently
Thermogenic response is impaired
They struggle to maintain body temperature
Adaptive thermogenesis is blunted
Energy expenditure and gene expression profiles shift negatively
Without 12-LOX, the body loses a key metabolic gear.
This shows cold adaptation isn’t just “mental toughness.” It’s biochemical precision.
Obesity Selectively Suppresses 12-HEPE Production
The vast majority of adults in the US are overweight or obese. Diet-induced obesity creates another problem:
12-HEPE levels in BAT fall sharply
Other 12-LOX products do not fall in the same way—this suppression is specific
Systemic glucose control worsens
BAT loses metabolic flexibility
But here’s the good news: administering 12-HEPE restores glucose metabolism even in obese mice, indicating a potential therapeutic route.
Cold exposure + omega-3 intake may help reawaken a suppressed pathway. While I would never suggest that ice baths are a short cut to fixing obesity, it’s a potential tool you can leverage on your path to staying fit to fight. However, no amount of “bio-hcking” is going to make up for 23 1/2 hours of bad habits. You can’t outtrain a bad diet. Getting your basics down is always Ground Zero.
If you’re struggling with getting a sustainable pattern of behavior off the mats, consider my Fit To Fight coaching program, where I offer guidance, support, and accountability. Research has shown that those who seek coaching do better than those who go it alone.
Our “Fit To Fight” one-on-one health coaching program can help you succeed!
Practical Takeaways for Your Fit To Fight Lifestyle
Here’s what this means for real people trying to stay strong, lean, and ready:
Cold exposure is a metabolic amplifier. You’re not just suffering—you’re flipping a metabolic switch.
Brown fat is an active organ of glucose control. It senses the environment and signals the rest of your body.
Metabolic flexibility is a fight skill. Your ability to burn different fuels under stress determines performance and resilience.
Cold + movement is a powerful synergy. Both increase GLUT4 translocation. Together, they’re a force multiplier.
Your diet determines the raw materials for 12-HEPE. You can’t make high-octane fuel from garbage inputs.
This is where omega-3 intake becomes critical.
Supercharging the 12-HEPE Pathway With Omega-3 Intake
Your body cannot make 12-HEPE unless you supply it with EPA & DHA —the omega-3 fatty acids found in cold-water fish.
The problem? Modern diets are drowning in omega-6 fatty acids (especially linoleic acid from seed oils), and almost no one gets enough omega-3s.
High omega-6 intake + low omega-3 intake = A brown fat system that can’t efficiently run the 12-HEPE program.
By increasing omega-3 intake, you provide your body with the substrate it needs to synthesize 12-HEPE and enhance cold adaptation.
The Sardine Fast: A Real-World n=1 Demonstration
Nick Norowitz, MD, PhD, a Harvard-trained metabolic researcher, ran a fascinating n=1 experiment on himself.
Nick is extremely lean—very low body mass, very little insulation. In theory, he should be terrible at handling cold.
He ran a month-long sardine fast—meaning sardines were nearly the only food he consumed.
A few weeks in, in the middle of a cold Boston winter, he noticed something remarkable:
He became dramatically more cold-tolerant.
This is someone who should freeze instantly on a windy New England day. But after saturating his system with EPA and DHA from sardines, his cold tolerance skyrocketed.
Mechanistically, this makes perfect sense:
Sardines are extremely high in omega-3s
Omega-3s are the substrate for 12-HEPE
More substrate → more 12-HEPE → stronger metabolic and thermogenic response to cold
Nick’s experiment is extreme, but it highlights the principle: If you give your brown fat more omega-3 building blocks, it gets better at cold adaptation.
How to Use Omega-3 Intake Smartly (Without Going Off the Deep End)
You don’t need to live on sardines year-round. But increasing your intake of fatty fish can significantly enhance this pathway.
Good sources include:
Sardines
Mackerel
Salmon
Anchovies
Herring
A few caveats:
Too much fatty fish can raise mercury and arsenic levels
A sardine-only diet is not a long-term strategy
Fatty-fish “cycles” may be ideal—boosting omega-3 intake periodically to prime cold adaptation and metabolic health
Use it like a training camp: Intensive when needed, strategic, and purposeful.
Final Thoughts
This paper uncovers the metabolic circuitry behind cold exposure. It shows that brown fat doesn’t just burn calories—it produces signaling molecules that improve glucose handling, amplify thermogenesis, and enhance whole-body metabolic resilience.
Got it. Here’s a replacement closing section that matches your voice and frames this properly in a Fit To Fight / preparedness context, without the AI-ish wrap-up language. You can drop this in place of the “Final Thoughts” section as-is.
Improving cold tolerance through omega-3 intake and brown fat activation probably isn’t going to make your arm drag sharper or your timing on the mats magically better. That’s not the claim, and it shouldn’t be.
But performance on the mats is only one narrow slice of what it means to be capable.
Cold tolerance, metabolic flexibility, and glucose control live upstream from technique. They shape how well you handle stress, fatigue, disrupted sleep, caloric restriction, illness, and environmental exposure. Those things matter far more often in real life than how clean your favorite throw looks in a controlled setting.
If you strip self-defense down to “how good am I at violence,” you miss most of the problem space.
Preparedness is about being functional when conditions aren’t ideal: when you’re cold, underfed, tired, distracted, or forced to operate outside your normal routines. A body that can efficiently regulate temperature and fuel use under stress is simply harder to break.
From that perspective, cold exposure combined with adequate omega-3 intake isn’t a performance hack. It’s resilience training. It’s about building a system that adapts instead of panicking when the environment pushes back.
That’s the deeper value here.
Being Fit To Fight means you don’t just train skills—you train the organism that has to express them, in the real world, under imperfect conditions.
Ashe is a highly skilled martial arts instructor and certified nutrition coach with over two decades of experience in the field. He holds a Master Instructor certification in I Liq Chuan under Sam FS Chin, making him one of only several individuals worldwide to hold the title. He has taught classes and workshops worldwide and is passionate about helping others achieve their fitness and wellness goals.
With a background in full-contact fighting and a Level 2 certification from Precision Nutrition in nutrition coaching, Ashe is a well-rounded expert in the fields of martial arts. In addition to his expertise, he has a wealth of experience in teaching and mentoring others. He has a natural ability to connect with his students and inspire them to reach their full potential.
I am not a doctor or a lawyer, and the information provided should not be considered medical or legal advice.
The information provided is for educational and informational purposes only and should not be used as a substitute for professional legal or medical advice, diagnosis, or treatment. Consult your doctor or a qualified healthcare professional before making any changes to your diet, exercise routine, or lifestyle.
Please note that some of the links provided in this content may be affiliate links, meaning that I may receive a small commission if you purchase through them. However, please rest assured that any products or services recommended are based on my personal experience and belief in their value. I only recommend products or services that I have personally used and believe in.
Unmasking Creatine – Fuel for the Ageing Martial Artist
By now, I’m sure you’ve heard of creatine, but what is it, and as a martial artist, why should you care?
In the unforgiving world of martial arts, two primal forces clash; our relentless pursuit of mastery and the stark reality of our bodies’ advancing years. As we age, that high-octane kick doesn’t land as easily, the reflexes aren’t as lightning-fast, and recovery time feels like an eternity. For those of us grappling with the limits of age and ambition, we yearn for that something – a potential game-changer – to tip the scales back in our favor.
Enter creatine. This much-talked-about supplement is rumored to be the secret weapon in the fight against time and fatigue. Yet, in the chatter of locker rooms and online forums, it is shrouded in half-truths and bro science. Does it boost performance, or is it just another overhyped supplement? Does it risk our health or help us maintain our fighting edge?
In this “Fit To Fight installment,” we pull no punches. We’re stepping onto the mats with science to knock out the myths and highlight the facts surrounding creatine. We’ll explore what it is, what it does, and whether it’s the ally the mature martial artist needs in this fight against time. From daily dosages to potential side effects, we’ve got you covered. Get ready to discover if creatine can make you a better fighter, regardless of what the calendar says.
Fit To Fight
Welcome to another installment of Fit-To-Fight, the series where we explore the intersection between ancient practices and modern science as part of a more natural way of living.
This series aims to help you experience your best physical and mental health by incorporating these practices into your life. We explore exciting topics that will get you thinking about your fitness and martial arts routine in a whole new way.
What Is Creatine?
Creatine is a naturally occurring substance in the human body, particularly in our muscle cells. Creatine monohydrate is an organic compound with the chemical formula CNCH₂CO₂H. The human body produces around 1 to 2 grams of creatine per day, and the rest is taken in through diet, particularly from foods like meat and fish.
Chemically, it’s known as a quaternary ammonium compound, chiefly involved in facilitating energy production in our cells. Creatine acts as a reserve of quick energy, especially during high-intensity, short-duration exercises like weightlifting or martial arts moves where we need sudden bursts of power.
Creatine also comes in a synthesized form, which is sold as a dietary supplement. This form is chemically identical to the creatine naturally produced by our bodies. This supplement is popular among athletes and fitness enthusiasts due to its potential benefits in enhancing athletic performance, strength, muscle gain, and even cognitive (brain) function.
What Does Creatine Do?
Power Play: How Creatine Monohydrate Supercharges Your Muscles
Imagine your muscles are like high-performance cars. To accelerate rapidly or maintain top speed, they need high-octane fuel. This “fuel” in our bodies is a molecule called ATP (adenosine triphosphate). It’s what keeps our biological engines revving, powering everything from a lightning-fast jab to a knee-crushing kick.
But here’s the rub: the body’s ATP reserves are limited and depleted quickly during intense activity. It’s akin to draining your sports car’s gas tank after a high-speed run. That’s where creatine steps into the spotlight.
Picture creatine as your muscle’s pit crew. During those high-intensity bursts, when ATP is rapidly used up, creatine helps quickly regenerate ATP. It does this by donating a phosphate group to produce new ATP, effectively refueling your muscle car mid-race. The result? You can maintain that high-speed, high-power output for a little longer, making each workout or training session more effective.
So, creatine doesn’t give you energy per se. Instead, it’s more of a recovery tool, a “recharger” that helps replenish your body’s quickly-depleted energy stores. By aiding in ATP restoration, creatine allows you to train harder and more effectively, potentially leading to better performance and strength gains.
Whether launching a flurry of punches or executing a masterful sweep, creatine is the pit crew your muscles need to go that extra round. But, like any supplement, it’s not a magic bullet. It must be considered within the broader scope of diet, exercise, and lifestyle. Stay tuned as we tackle more questions about creatine, so you can decide if it’s right for your fitness journey.
Is Creatine Bad For You?
Performance Booster or Health Hazard?
By nature’s design, creatine is not the bogeyman it’s sometimes made out to be. After all, our bodies craft it daily from amino acids in the liver. It’s like the body’s in-house blacksmith, fashioning an essential tool for high-performance activity. That tells us something about its value.
There’s a pervasive myth linking creatine to kidney damage. It hinges on the fact that creatine supplementation increases creatinine levels in the body. For the uninitiated, creatinine is a waste product often used as a marker of kidney health. Higher levels can indicate kidney problems, leading some to draw a dangerous line connecting creatine to kidney harm.
But here’s the catch: research has shown that increased creatinine levels due to creatine supplementation are not a sign of kidney damage in otherwise healthy individuals. It’s more like a harmless false alarm triggered by the body processing the extra creatine, akin to the effects of increased dietary protein. Bruce Lee, a paragon of martial arts and fitness, was a creatine user. His legendary status, formidable power, and enduring legacy speak volumes about this supplement’s long-standing efficacy and safety. The science concurs: for healthy individuals, judicious use of creatine is safe, supported by numerous studies endorsing its long-term use.
To recap: creatine isn’t your adversary—it’s a trusted companion in every fighter’s corner, ready to back you up in your martial arts journey.
Is Creatine Good For Martial Arts?
Powering the Punch: Turbocharge Your Martial Arts Game
Martial arts aren’t just about strength; it balances power, endurance, and speed. Can creatine help you strike harder and grapple longer? Emerging science suggests it is your secret weapon.
Creatine is like a trusted cornerman, boosting your muscular strength and enhancing anaerobic power. Think of it as an extra gear, allowing you to go harder, faster, and more effectively during those high-stakes sparring sessions and grueling workouts.
But that’s not all. Creatine takes your muscle cells to the hydration station, leading to what’s known as ‘hyper-hydration.’ This is akin to supercharging your muscles’ water retention capacity, helping to increase glycogen storage – that’s your muscles’ ready-to-use energy reserve. More glycogen equals more fuel for your martial arts training, letting you push harder and go longer.
Another unseen advantage is reduced muscle damage. After those heavy-duty workouts, your muscles are like warriors returning from battle – bruised, battered, and needing repair. Here, creatine steps in as the medic, decreasing markers of muscle damage and accelerating recovery.
The upshot? More work capacity, improved recovery, and over time, potentially more muscle hypertrophy and strength. This doesn’t just translate to a better physique but also a more potent martial arts performance.
Yet, remember, creatine is an ally, not a miracle worker. It works best with a balanced diet, a consistent training regimen, and plenty of rest and recovery. So, if you’re eyeing that extra edge in your martial arts journey, creatine might be worth considering.
Is Creatine Illegal In Combat Sports?
Legal Boost or Banned Substance?
The arena of combat sports has stringent rules, especially around performance-enhancing substances. So, is creatine classified as a legal supplement?
According to the United States Anti-Doping Agency (USADA), the referee of fairness in sports, creatine gets the green light. It’s not on their list of banned substances, meaning athletes, including martial artists, can use it without breaking the rules.
However, when shopping for creatine, it’s a buyer-beware market, and you should vet your creatine source. Buying from reputable manufacturers based in the US, Canada, or Germany that adhere to good manufacturing practices is a smart move.
Why the caution? Some supplements, particularly those from China, may contain heavy metals or be produced in facilities that also handle banned substances. It’s a classic case of cross-contamination that could result in an accidental failed drug test.
The Mindful Warrior: Can Creatine Boost Your Brainpower?
Martial arts is as much about mental acuity as physical prowess. Creatine, often celebrated for its muscle-boosting benefits, might also have a starring role in the theater of the mind.
Creatine’s cognitive-enhancing potential shines especially bright in certain groups. Vegans and the elderly, who are more likely to be creatine deficient, may find it particularly beneficial. Creatine can step in to refill the body’s lower reserves, potentially sharpening mental focus and cognition.
Beyond this, creatine shows promise in more challenging scenarios, where the brain’s energy demands – and consequently ATP turnover – are high. Think of it as bringing a supercharged battery pack to an energy-intensive party.
Those late-night training sessions when sleep deprivation gnaws at your focus? Creatine might help keep your mind sharp. When you’re grappling with complex strategies or decoding an opponent’s moves? It could offer that mental edge.
While empowering and thrilling, martial arts carries the inherent risk of concussions and traumatic brain injuries (TBIs). Blows to the head can be part of the game. Interestingly, creatine may play a defensive role here. Some studies suggest it can aid brain recovery post-injury, offering a potential protective effect against such risks. So, beyond muscle power, creatine might also be your brain’s ally on the mats.
By bolstering brain ATP, creatine ensures your mental engine has the juice to run optimally, even under demanding conditions. Remember that while the scientific picture is promising, it’s still developing. Further research is needed to comprehend creatine’s cognitive potential fully.
Bottom line? Creatine might amplify your physical game and potentially sharpen your mental edge, making you a more formidable martial artist both in body and mind. But how much creatine is ideal, and when should you take it? We’re ready to tackle that in the next section!
Get Fit To Fight
The dojo is the easy part. What we do off the mats matters just as much as what we do on the mats. 1:1 health coaching for martial arts to get you fit to fight.
What Is The Proper Way To Take Creatine?
Tuning Your Strategy: From Loading to Maintenance
The road to creatine optimization can be viewed in two stages – Loading and Maintenance. Let’s break these down.
Loading Phase
During the Loading phase, a guideline of 0.3 g/kg/day, split into four intervals, is suggested, given that creatine needs can vary with body weight. An alternative path is a slower pace, where taking 3 grams a day for 28 days could increase muscle creatine storage to similar levels as a speedy load-up of 20 g/day over just six days. Remember that creatine’s benefits will be fully felt once your muscles are fully loaded, like a well-tuned engine ready to roar.
Loading Phase:
Lasts 5-7 days.
Daily: 0.3 g/kg body weight.
Divide into 4 doses.
Or, slower load: 3g/day for 28 days.
Maintenance Phase:
Shift to 3-5 g/day post-loading.
Maintain this daily.
Taking creatine with carbohydrates or carbs plus protein can enhance creatine retention, much like a well-timed punch can deliver a more potent impact. This increase in muscle creatine storage is linked with the performance-boosting benefits we’ve discussed.
Maintenance Phase
Once you’ve hit the 5-7 day mark in the Loading phase, you’re onto Maintenance. At this point, your muscle creatine stores are fully saturated, like a water balloon ready to burst. Your supplementation now only needs to cover the amount of creatine broken down daily. This was initially reported to be around 2-3 g/day, but recent research suggests a 3-5 g/day dose could better maintain those fully loaded creatine levels.
With your creatine strategy finely tuned, you’re ready to step back onto the mats, powered by science.
So, you’re considering making creatine your training ally. But like learning the right stance or mastering a precise move, there’s a proper way to take creatine too.
When it comes to form, creatine monohydrate wears the championship belt. A daily dose of 5 grams post-workout is typically recommended. Timing it right is key – just as you wouldn’t execute a roundhouse kick at the wrong moment.
Why after your workout? When your muscles have been tested in the mats or the gym, they’re ready to absorb nutrients, a state we can liken to a sponge freshly wrung out and ready to soak up water. Adding carbohydrates and protein to the mix further enhances creatine absorption, creating a potent recovery cocktail. It’s like the perfect one-two punch, knocking out muscle recovery and performance optimization in one swing.
Conclusion
Creatine, a naturally occurring compound in our bodies, steps into the mats as a potential ally in the ceaseless fight against age and time. It is not an elixir of youth nor an overblown myth; it is a supplement with proven benefits in replenishing energy stores and enhancing high-intensity performance – the very attributes a martial artist needs to endure the grueling gauntlet of training and competition.
Does creatine turn the clock back? No. Does it promise unending strength and stamina? Certainly not. It offers a potentially improved training outcome, faster recovery, and an edge against opponents. It’s not a miracle worker, but it can be a potent tool in a martial artist’s demanding regime.
From the aging martial artist grappling with the challenges of time to the passionate novice striving for an edge and to every warrior in between – this edition of “Fit To Fight” is dedicated to you. As we walk this path together, we know that the quest for mastery never ends; it merely evolves. In the arena of martial arts, victory lies not in conquering opponents but in the constant pursuit of becoming better, stronger, and wiser. Here’s to that quest, and here’s to the martial artist in each of us. Let the journey continue.
Ashe is a highly skilled martial arts instructor and certified nutrition coach with over two decades of experience in the field. He holds a Master Instructor certification in I Liq Chuan under Sam FS Chin, making him one of only several individuals worldwide to hold the title. He has taught classes and workshops worldwide and is passionate about helping others achieve their fitness and wellness goals.
With a background in full-contact fighting and a Level 2 certification from Precision Nutrition in nutrition coaching, Ashe is a well-rounded expert in the fields of martial arts. In addition to his expertise, he has a wealth of experience in teaching and mentoring others. He has a natural ability to connect with his students and inspire them to reach their full potential.
I am not a doctor or a lawyer, and the information provided should not be considered medical or legal advice.
The information provided is for educational and informational purposes only and should not be used as a substitute for professional legal or medical advice, diagnosis, or treatment. Consult your doctor or a qualified healthcare professional before making any changes to your diet, exercise routine, or lifestyle.
Please note that some of the links provided in this content may be affiliate links, meaning that I may receive a small commission if you purchase through them. However, please rest assured that any products or services recommended are based on my personal experience and belief in their value. I only recommend products or services that I have personally used and believe in.
While martial arts like Tai Chi can be a great way to manage chronic pain and improve overall health, two key lifestyle factors – vitamin D and magnesium – can also play a significant role. Vitamin D, often known as the “sunshine vitamin,” is crucial for bone health and immune function, while magnesium is a key player in muscle function and energy production. Both of these nutrients can not only help manage pain, but they can also maximize performance for martial artists who are already healthy. So, in this week’s “Fit To Fight,” we’ll dive deeper into the roles of vitamin D and magnesium and how they can help you on your martial arts journey.
Welcome to another installment of Fit-To-Fight, the series where we explore the intersection between ancient practices and modern science as part of a more natural way of living.
This series aims to help you experience your best physical and mental health by incorporating these practices into your life. We explore exciting topics that will get you thinking about your fitness and martial arts routine in a whole new way.
Vitamin D Deficiency & Magnesium Deficiency For Chronic Pain
Chronic pain is a prevalent condition that affects millions of people worldwide. It can be caused by various factors, including autoimmune diseases, injuries, and nerve damage. In recent years, there has been a growing interest in the potential benefits of vitamins and minerals in the management of chronic pain. Two such nutrients that have garnered attention are Vitamin D and Magnesium.
What Is Vitamin D?
Vitamins are like the helpful friends our bodies need to work properly. They act as co-factors or co-enzymes, which means they help proteins in our body complete chemical reactions, like breaking down our food or building our cells. Some vitamins are water-soluble, which means they dissolve in water and leave the body quickly. Others are fat-soluble, which means they can be stored in our body’s fat and used over time. So, whether it’s helping us get energy from our food or keeping our skin healthy, vitamins are key players in keeping us feeling and performing our best.
Vitamin D3, also known as cholecalciferol, is a type of steroid hormone. Steroid hormones are powerful chemicals that can travel through the body and cause various changes. They’re like messengers, delivering important instructions to our cells.
What Is Magnesium?
Magnesium is the fourth most common mineral in our body and the second most common positively charged particle found inside your body’s cells, playing a crucial role in many of the body’s functions, including as an electrolyte. It is needed for about 300 enzymes in the body and may help with various conditions such as sugar absorption, high blood pressure, pain, mood, and sleep.[1]
Magnesium Deficiency & Benefits
Magnesium deficiency is a common problem, especially among people who consume a low-magnesium diet (which is pretty much everybody in the 21st century).
Symptoms of magnesium deficiency include muscle cramps, heart palpitations, anxiety, and fatigue. Magnesium supplementation may help with:
Pain relief
Sleep
Mood improvement
Conditions such as neuropathy, migraines, and chronic regional pain syndrome.
Autoimmune Diseases & Chronic Pain
Autoimmune diseases, such as lupus, rheumatoid arthritis, and multiple sclerosis, can cause chronic pain. These conditions occur when the immune system mistakenly attacks healthy cells in the body, resulting in inflammation and pain.
Vitamin D Benefits
Vitamin D is like a multitasking superhero for our bodies. We all know it’s important to keep our bones and teeth strong, but it does much more.
Imagine vitamin D as a master controller that can turn on and off certain functions in our body. It does this by interacting with special areas in our cells called vitamin D response elements. It’s like flipping a switch to activate over 900 different genes in our body.[2]
One of the key roles of vitamin D is to help our body absorb and use calcium, which is crucial for strong bones and teeth. But it doesn’t stop there. Vitamin D also helps our cells grow properly and can even slow down the growth of some cancer cells.
This study found that men with sufficient vitamin D levels had significantly higher levels of testosterone than those with insufficient or deficient vitamin D levels, revealing a concordant seasonal variation between vitamin D and androgen levels.[7]
Vitamin D also plays a role in our immune system. It can help control how our immune cells respond to threats, ensuring they react just the right way.
Vitamin D has been shown to improve:
Autoimmune disorders[5]
Testosterone levels
Diabetes
Muscle function, mood, and sleep
Immune system and recurrent infections
Heart health
In a nutshell, vitamin D is a vital part of many different processes in our bodies. From our bones to our immune system, it helps keep us healthy in more ways than we might realize.
Vitamin D Levels
Vitamin D levels in our body can be a bit tricky to measure. The best way we currently have is to look at the levels of a form of vitamin D called 25(OH)D3 in our blood. This gives us a good idea of how much vitamin D we’re getting from sunlight, food, and supplements. But it doesn’t tell us how much vitamin D is stored in our body’s tissues.
We also look at parathyroid concentrations, which can give us a better idea of how our body uses vitamin D.
When we talk about vitamin D levels, we usually use units like nanomoles per liter (nmol/L) and nanograms per milliliter (ng/mL).
Vitamin D insufficiency is defined when the levels of 25-hydroxyvitamin D (25OHD) are between 20–29 ng/mL
Deficiency is considered when the levels are ≤20 ng/mL.
Adequate levels of vitamin D are generally defined as a serum concentration of 25-hydroxyvitamin D (25OHD) of 30 ng/mL or above.
How Is Vitamin D Made
Here’s how our bodies create this superhero, vitamin D3: When our skin gets some sunshine, a substance in the skin called 7-dehydrocholesterol gets excited and transforms into pre-vitamin D. This pre-vitamin D then changes itself into vitamin D3.
Once D3 is formed, it hops into our bloodstream and travels to the liver. It changes into a new form called 25-hydroxyvitamin D, or 25(OH)D. This is the main type of vitamin D that circulates in our bodies.
But the journey doesn’t end there. The 25(OH)D then heads to the kidneys, where it transforms into its most active form, 1α,25-dihydroxyvitamin D, or 1,25(OH)2D. This superhero version of vitamin D does all the amazing things we’ve discussed, like helping our bones and immune system. This whole process is carefully controlled by our bodies, ensuring everything happens just right.
However, the amount of Vitamin D produced from sunlight exposure can vary depending on several factors, such as time of day, season, skin color, and geographical location.
In Arizona, we’re lucky to be close enough to the equator that we can get some vitamin D all year round, depending on the time of day. However, anywhere north of Atlanta, you can only get vitamin D from sun exposure between April and October.
Magnesium And Vitamin D Research Studies
Several research studies have shown a correlation between Vitamin D and Magnesium levels and chronic pain. One study found that taking Vitamin D and Magnesium supplements together can help reduce pain and improve the overall quality of life in patients with fibromyalgia. Another study found that Magnesium supplementation can help reduce pain in patients with chronic lower back pain.
Magnesium & Chronic Pain
Magnesium is important for nerve function and may help alleviate chronic pain. It works by blocking N-methyl-D-aspartate (NMDA) receptors, which are involved in the transmission of pain signals to the brain.[3] Magnesium supplementation may also help improve sleep quality, which can be beneficial for individuals with chronic pain.[4]
Magnesium Benefits
Magnesium has many benefits for the body. It helps regulate blood pressure, supports the immune system, and aids in the absorption of calcium. Magnesium may also play a role in mood regulation and can help alleviate symptoms of anxiety and depression. We’ll go into depth on all the benefits of magnesium in another article; for now, we’ll focus on the interaction between magnesium and vitamin D.
Magnesium & Vitamin D
Magnesium works with Vitamin D by helping it bind to transport in the blood vessels and converting basic forms of Vitamin D to more functional forms. This process is essential for the body to utilize Vitamin D effectively.[6]
Magnesium plays a crucial role in the conversion of pro-vitamin D into active Vitamin D3 in the body.
Vitamin D starts as cholesterol in the body and goes through a conversion process to become 25 hydroxy Vitamin D through the catalyzation of UV light.
This 25 hydroxy Vitamin D further converts to 1,25 hydroxy Vitamin D, also known as calcitriol, which is the active form of Vitamin D in the body.
Magnesium is needed to help convert the basic forms of Vitamin D to the more advanced forms that are functional in the body.
Additionally, Magnesium assists in the binding of Vitamin D to transport in the blood vessels, further supporting its role in Vitamin D metabolism.
Magnesium Foods
Dark, leafy green foods are your best source of magnesium from foods. Almonds and dark chocolate are other options. However, some people are sensitive to oxalates in dark, leafy greens or allergic to foods like almonds and chocolate.
Large-scale, mono-crop agriculture has depleted our soils over time, which means that the micronutrient density of fruits and vegetables today is not as high as it was in the past, so even if you eat plenty of fruit and veg, you may not be getting enough magnesium to meet your needs, especially if you’re a hard-charging athlete or martial artist, so you may still benefit from supplementing with additional magnesium.
Best Way To Take Magnesium Dosage
The current Recommended Dietary Allowance (RDA) for magnesium for adult men is 400-420 mg per day and 310-320 mg per day for adult women.
It’s important to consult with a doctor before starting magnesium supplementation, especially for individuals with kidney problems. Avoid taking magnesium supplements with dairy.
Best Magnesium Supplements
Getting sufficient magnesium through food alone can be challenging, and absorption through the gut may be limited, so supplements and topical sprays are alternative options.
The research around magnesium sprays and creams has mostly been sponsored by manufacturers of those products. Independent research has shown that topical magnesium is not well absorbed, so for that reason, I prefer to supplement with caps. My favorite brand is BioEmblem Triple Magnesium Complex.
Vitamin D Deficiency
Vitamin D is a crucial nutrient that our bodies need for many functions. Despite this, over a billion people around the world don’t get enough of it.[8] This isn’t just about strong bones – lack of vitamin D can lead to a host of health problems, from heart disease and diabetes to certain types of cancer.
The study “Prevalence of Vitamin D Deficiency and Associated Risk Factors in the US Population (2011-2012)” looked at how common vitamin D deficiency is among different groups of people in the United States, using health data from over 4,900 adults.[9]
Here are some key points to consider:
Race and Vitamin D Deficiency: The study found that race was a significant risk factor for vitamin D deficiency. African-American adults had the highest vitamin D deficiency prevalence rate, followed by Hispanic adults. This is due to the increased melanin levels found in the skin of these races, which absorbs and scatters ultraviolet rays from sunlight, resulting in less efficient conversion of 7-dehydrocholesterol to pre-vitamin D3, a precursor of vitamin D.
Age and Vitamin D Deficiency: Contrary to common belief, the study found an increased incidence of vitamin D deficiency among participants aged under 65 years of age, thus refuting the commonly accepted notion that increasing age is directly proportional to the risk of being vitamin D deficient.
Education, Health Status, and Vitamin D Deficiency: The study found that individuals with college education had statistically significantly lower rates of vitamin D deficiency. Similarly, individuals with poor/fair health status were more likely to be vitamin D deficient.
Smoking and Vitamin D Deficiency: The study found that current smokers were more likely to be vitamin D deficient. This may be related to the ability of sinus mucosa to activate circulating vitamin D levels, which is impaired in smokers.
Obesity and Vitamin D Deficiency: The study showed statistically significant differences in vitamin D deficiency rates with respect to weight, with a higher percentage of vitamin D deficient participants falling under the category of obese (BMI ≥30).
Daily Milk Product Consumption and Vitamin D Deficiency: The study found that daily consumption of milk products serves as an effective prophylaxis against vitamin D deficiency in conjunction with daily sun exposure.
Cancer and Vitamin D Deficiency: Contrary to established associations, the study found a statistically significant higher rate of cancer among the vitamin D sufficient population compared to the vitamin D deficient population.
Diabetes and Vitamin D Deficiency: The study found a statistically significant relationship between vitamin D deficiency and diabetes, supporting growing evidence suggesting vitamin D deficiency is a contributing factor to the development of both type 1 and type 2 diabetes.
Our bodies usually make vitamin D when our skin is exposed to sunlight. But most people spend over 90% of their time indoors. Combined with an indoctrinated sense of fear of the sun, most people cover their bodies with sunscreen and clothing when outside, meaning most of us don’t get nearly enough sun exposure to match ancestral levels of vitamin D.
To tackle this, we need to educate people about the importance of vitamin D, check people’s vitamin D levels regularly, and make sure our food contains enough of this vital nutrient. It’s a big task, but one that could make a huge difference to our global health.
Best Way To Get Vitamin D
Sunlight exposure is the best way to get Vitamin D. 10 to 15 minutes of sun exposure per day is recommended as it has additional benefits beyond Vitamin D production. The darker skinned, or the further north you live, the longer it takes to generate enough vitamin D. If sunlight exposure is limited, Vitamin D supplements, particularly Vitamin D3, can be taken. However, caution should be exercised to avoid toxicity.
Best Vitamin D Supplements
Vitamin D supplements come in various forms, such as Vitamin D2 and Vitamin D3. Vitamin D3 is the more active form of Vitamin D and is preferred by most health professionals.
Dr. Weston A Price was a pioneer in research on nutrition and degenerative disease. He knew that vitamin D worked in concert with another compound that was unidentified at the time, which he referred to as “activator x.” In the modern era, many researchers now believe that “activator x” is vitamin k2. While vitamin D helps the body absorb calcium, vitamin K2 helps shuttle it to the correct places in the body and away from areas we don’t want it deposited (like the arteries). For this reason, it’s important to supplement with both of them in the correct ratios.[10] That’s why I prefer Thorne Labs Vitamin D3/K2 combo.
Thorne Labs is a trusted health supplement company known for its high-quality products and adherence to good manufacturing practices. When supplementing with something as important as Vitamin D3, it’s crucial to choose a reputable manufacturer like Thorne Labs to ensure you’re getting a safe and effective product.
Vitamin D Dosage
The recommended daily dose of Vitamin D varies depending on age, sex, and health status. It’s important to consult with a doctor before starting Vitamin D supplementation to determine the appropriate dosage.
The current Recommended Dietary Allowance (RDA) for Vitamin D for adults aged 18-70 is 600 International Units (IU) per day, and for adults over 70, it’s 800 IU per day.
While the recommended doses of Vitamin D are typically around 600 to 800 International Units (IU) per day, this might be less than what our bodies naturally produce – about 25,000 units per day – when we spend time in the sun. In fact, a seven-year study found that giving hospitalized patients daily oral doses of Vitamin D3, ranging from 5,000 to 50,000 IU, was safe and well-tolerated.[11] This long-term supplementation of Vitamin D3 not only appeared to be safe, but it also led to improved health outcomes without any adverse reactions. Interestingly, the study found that it took around 12 months for blood levels of Vitamin D to plateau with daily doses of 5,000 to 10,000 units, suggesting that our bodies slowly absorb and utilize this vital vitamin.
Light Therapy For Vitamin D
Light therapy and phototherapy have proven benefits beyond Vitamin D production, including improved sleep, mood, and overall well-being. Light therapy involves exposure to light that mimics natural sunlight and can be beneficial for individuals with limited sun exposure.[12]
In the 1930s, vitamin D lamps were a popular way to combat vitamin D deficiency, especially in areas with limited sunlight. These lamps emitted ultraviolet B (UVB) light, which our skin uses to produce vitamin D naturally. People would sit in front of these lamps, much like a sunbathing session, to boost their vitamin D levels. This was particularly useful during winter months or in places with long periods of darkness. Bonus: you will tan (or possibly burn) when using a Sperti!
The Sperti Lamp is a specialized UV lamp designed to help the body naturally produce vitamin D. It was developed by Dr. George Sperti, known for his research in the field of photobiology. The lamp emits UVB light, the same type of light that triggers vitamin D production in our skin when we’re exposed to sunlight. This makes the Sperti Lamp a useful tool for people who may not get enough sun exposure, especially during winter months or in regions with less sunlight. The main benefit of using phototherapy for vitamin D is there is no risk of vitamin D toxicity, as is a potential with nutritional supplements.
Light Therapy For SAD
A full-spectrum light therapy panel can be a great option for those dealing with Seasonal Affective Disorder (SAD). These panels emit light that covers the entire spectrum of natural sunlight. This type of light can help regulate sleep patterns and mood, which are often disrupted in people with SAD. It’s important to remember that light therapy should be used under the guidance of a healthcare professional, as they can provide advice on how to use the panel safely and effectively.
Get Fit To Fight
The dojo is the easy part. What we do off the mats matters just as much as what we do on the mats. 1:1 health coaching for martial arts to get you fit to fight.
Ashe is a highly skilled martial arts instructor and certified nutrition coach with over two decades of experience in the field. He holds a Master Instructor certification in I Liq Chuan under Sam FS Chin, making him one of only several individuals worldwide to hold the title. He has taught classes and workshops worldwide and is passionate about helping others achieve their fitness and wellness goals.
With a background in full-contact fighting and a Level 2 certification from Precision Nutrition in nutrition coaching, Ashe is a well-rounded expert in the fields of martial arts. In addition to his expertise, he has a wealth of experience in teaching and mentoring others. He has a natural ability to connect with his students and inspire them to reach their full potential.
I am not a doctor or a lawyer, and the information provided should not be considered medical or legal advice.
The information provided is for educational and informational purposes only and should not be used as a substitute for professional legal or medical advice, diagnosis, or treatment. Consult your doctor or a qualified healthcare professional before making any changes to your diet, exercise routine, or lifestyle.
Please note that some of the links provided in this content may be affiliate links, meaning that I may receive a small commission if you purchase through them. However, please rest assured that any products or services recommended are based on my personal experience and belief in their value. I only recommend products or services that I have personally used and believe in.
References
Volpe, Stella Lucia. “Magnesium in disease prevention and overall health.” Advances in nutrition 4.3 (2013): 378S-383S. (https://doi.org/10.3945/an.112.003483)
Reference: Wang, Tian-Tian, et al. “Large-Scale in Silico and Microarray-Based Identification of Direct 1,25-Dihydroxyvitamin D3 Target Genes.” Molecular Endocrinology, vol. 19, no. 11, 2005, pp. 2685–2695, [DOI: 10.1210/me.2005-0106](https://dx.doi.org/10.1210/me.2005-0106).
Cao, Yingting, et al. “Magnesium intake and sleep disorder symptoms: findings from the Jiangsu Nutrition Study of Chinese adults at five-year follow-up.” Nutrients 10.10 (2018): 1354. (https://doi.org/10.3390/nu10101354)
Hahn, Jill, et al. “Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial.” Bmj 376 (2022). (https://doi.org/10.1136/bmj-2021-066452)
Uwitonze, Anne Marie, and Mohammed S. Razzaque. “Role of magnesium in vitamin D activation and function.” Journal of Osteopathic Medicine 118.3 (2018): 181-189. (https://doi.org/10.7556/jaoa.2018.037)
Wehr, E., et al. “Association of vitamin D status with serum androgen levels in men.” *Clinical Endocrinology*, vol. 73, no. 2, 2010, pp. 243-248,. DOI: 10.1111/j.1365-2265.2009.03777.x. (https://doi.org/10.1111/j.1365-2265.2009.03777.x)
Naeem, Zahid. “Vitamin D Deficiency- An Ignored Epidemic.” *International Journal of Health Sciences*, vol. 4, no. 1, 2010,. (https://pubmed.ncbi.nlm.nih.gov/21475519)
Parva, Naveen R., et al. “Prevalence of vitamin D deficiency and associated risk factors in the US population (2011-2012).” Cureus 10.6 (2018). (https://doi.org/10.7759/cureus.2741)
Mandatori, Domitilla, et al. “The dual role of vitamin K2 in “bone-vascular crosstalk”: opposite effects on bone loss and vascular calcification.” Nutrients 13.4 (2021): 1222. (https://doi.org/10.3390/nu13041222)
McCullough, Patrick J., Douglas S. Lehrer, and Jeffrey Amend. “Daily oral dosing of vitamin D3 using 5000 TO 50,000 international units a day in long-term hospitalized patients: Insights from a seven year experience.” The Journal of steroid biochemistry and molecular biology 189 (2019): 228-239. (https://doi.org/10.1016/j.jsbmb.2018.12.010)
Rosenthal, Norman E., et al. “Seasonal affective disorder: a description of the syndrome and preliminary findings with light therapy.” Archives of general psychiatry 41.1 (1984): 72-80. (https://doi.org/10.1001/archpsyc.1984.01790120076010)
