Vitamin D

Vitamin D

Vitamin D - crucial to ensuring your test levels are healthy.

tl; dr ... Short and to the Point
Who is this article aimed at?
Anybody looking at supplementing with Vitamin D, or buying a combined supplement including Vitamin D. Anybody wanting details of the research into Vitamin D, and the associated health benefits.
I am busy - summarize it for me

In a nutshell: Vitamin D is extremely important for your test levels. If you live in North America or Northern Europe and work in an office there's every chance you have low Vitamin D levels.

There have been numerous quality studies done on humans establishing a firm link between Vitamin D and test, but it's hard to find one that disproves the link.

Achieving true health is all about leading an active lifestyle, eating the right foods and taking the right supplements to support your body. That’s where vitamin D comes in.

Supplements support a healthy lifestyle. They aren’t designed to replace a good diet and plenty of exercise; but what they do well is ‘supplement’ it. They just help you on your journey.

For the most part, supplement different nutrients may or may not help you. But there are some natural nutrient supplements that practically everyone should be taking to improve wellness and physical performance. There aren’t many of them, but they do exist… and vitamin D is most definitely one of those.

In this article we’ll break down the science and show you why the ‘sunshine vitamin’ improves pretty much every aspect of your life – from enhancing physical performance to boosting mood, improving recovery and reducing the risk of health-related illness.

We’ve got it all…

What is Vitamin D?: A run through the science

“Vitamin D is a hormone nutrient that regulates numerous functions in the human body. It’s more than just a simple vitamin”

Vitamins are organic compounds that don’t directly supply your body with energy but support how energy is used by your body. They’re classed as essential because your body can’t synthesize them and must obtain them from food.

The vitamins you get naturally from your diet can be split into two categories:

  • Water soluble – dissolve in water and aren’t stored in the body. They include all of the B vitamins as well as vitamin C.
  • Fat soluble – dissolve in fat and are stored in fatty tissue ready to be used by the body when needed. A, D, E and K are all fat soluble.

Vitamin D (25(OH)D) isn’t like other vitamins. In fact, it’s not really a vitamin at all but a secosteroid – it has a direct effect on your endocrine system and the hormones that it regulates.

Basically, vitamin D acts more like a hormone than anything. Many scientists and nutritionists refer to it as the ‘sixth steroid hormone’ for that reason. And that makes it even more important when it comes to optimal health.

It’s all about ‘the sunshine nutrient’

There’s one huge difference between 25(OH)D and other vitamin nutrients. Your skin makes its own vitamin D when it’s exposed to the UV rays of the sun. That’s why we refer to it as the ‘sunshine nutrient’.

The chemical pathway that sunlight takes to make vitamin D is lengthy. But these are some of the important steps that occur during conversion:

  • Sunlight strikes your body
  • UVB rays penetrate your skin
  • Sunlight is converted to 7-dehydrocholesterol
  • 7-dehydrocholesterol is converted to calcidiol 25(OH)D which is how vitamin D levels are measured
  • 25(OH)D is finally converted to active vitamin D

You can’t make it if you’re in the dark, or even indoors (UV rays cannot pass through glass) so sunny weather is a must. Maybe it’s one of the reasons we feel so good when we’re relaxed on the beach or sat in the garden in the middle of summer (the gin and tonic also helps of course).

We don’t know exactly how much time you need to spend in the sun to stimulate enough vitamin D. This is mostly because several factors affect production – from the time of the year to the amount of melanin in your skin.

People with darker skin need more exposure to the sun compared to those with lighter skin.

You can get vitamin D from food… but absorption is poor

Although your body can make its own vitamin D, you can also obtain it from food, although this isn’t its favored source.

  • Oily fish such as sardines, mackerel, trout, herring, salmon and eels
  • Eggs, meat, organ meat
  • Butter, yogurt, fortified cereals, milk, infant formula

Although these are the foods with the highest relative concentration of vitamin D, the absolute amounts are low. For example, an egg only gives you 7% of your daily recommended amount, and even a significant portion of oily fish will give you less than the RDA (but with a lot of calories too!)

In other words, relying on 25(OH)D synthesis from food is a poor choice. It’s bioavailability is low.

Scientists agree that very few foods naturally contain or are fortified with vitamin D, and even a diet rich in these foods is unlikely to help you get sufficient amounts.

Chances are you aren’t getting enough vitamin D

Unless you live in a consistently hot and sunny climate, you aren’t getting enough vitamin D. According to recent statistics, 50% of the population worldwide don’t get enough of a vitamin D jump start from sunlight. That is known as insufficiency and defined by a blood level of 25-hydroxyvitamin-D (25 OHD) that falls below 32 ng/mL. 1 billion people worldwide are deficient, with a count of 25 ng/mL.

Some scientists have even suggested that vitamin D deficiency is a major global public health problem. It’s such a serious lack of the nutrient that many consider it to be a pandemic of hypovitaminosis D.

The Difference Between Vitamin D2 and D3

“D3 is more efficacious at raising serum 25(OH)D concentrations than is vitamin D2, and thus vitamin D3 could potentially become the preferred choice for supplementation”.

Once synthesized from the sun or obtained from food, vitamin D begins its journey into your bloodstream. Along the way are various chemical reactions and structural changes.

  • Vitamin D3, known as cholecalciferol, is the natural form of the nutrient, produced from the sun or in supplement form.
  • Vitamin D2 (ergocalciferol) is a compound formed when yeast encounters UV light.

There’s a substantial amount of evidence that D3 is a superior form of the vitamin, especially when it comes to absorption rate in supplement form. Various high-power meta-analysis studies have found that D3 increases serum 25(OH)D levels much more than D2 does.

What does this mean?

If you choose to supplement vitamin D (like we’ve already said, if you don’t live in a hot and sunny climate you more than likely need to), make sure you choose a high-quality vitamin D3 supplement.

That way you’ll not only maximize absorption rates and the health effects that come with it; you’ll also get more bang for your buck.

Vitamin D2 is a synthetically-made, low-quality drug that doesn’t naturally occur in the human body.

The Importance of Vitamin D3 for Health

“Low vitamin D levels are associated with increased overall and cardiovascular mortality, cancer incidence and mortality, and autoimmune diseases such as multiple sclerosis”.

Choosing the right supplement means making a conscious decision to improve your health. Some nutrients can boost heart health; others might help you perform better on the sports field or in the gym.

But vitamin D is different.

The sunshine nutrient enhances practically every single element of your life – from brain and vascular health, to muscle growth and recovery.

Here’s a breakdown of just some of the important benefits this supplement offers…

Improves life expectancy and quality of life

Vitamin D3 offers the fountain of youth. Seriously.

Not only does it reduce inflammation and oxidative stress build up (this can lead to rapid cell aging and degeneration), it also decreases risk of mortality.

A study published in the Archives of Internal Medicine in 2008 showed that adults with lower serum 25(OH)D were 26% more likely to die across the duration of the study.

That’s a huge increase.

Luckily, a highly-reliable meta-analysis found that when nearly 20 separate studies on vitamin D supplementation were analyzed, higher doses of 2,000 IU led to a decrease in risk of early death compared to doses of only 300 IU obtained from food.

Lower cardiovascular risk

Cardiovascular disease led to over 17.7 million global deaths in 2015, making it the world’s leading cause of mortality at 31% of total deaths.

There’s a significant relationship between low serum 25(OH)D levels and vascular-related illness. One study reported that over a 5-year period, those with lower vitamin D levels were likely to suffer a heart attack, or coronary event, with high blood pressure also being a key risk factor.

Brain boosting power

Older adults are at a significant risk of developing cognitive impairment and diseases such as dementia as they age. Vitamin D receptors are widespread within neuronal cells of your brain (specifically with a region called the hippocampus), making it an important aspect of overall cognitive health.

Older adults are at 4 times greater risk of developing Alzheimer’s disease compared to those with levels above the normal values of 75 nmol.L.

Vitamin D has also been shown to mitigate the risk of neurological illnesses such as multiple sclerosis. One study suggested that children exposed to sun are less likely to develop MS in later life, and another found that there are far fewer MS sufferers born in November than there are any other time of year – in other words, embryonic sun exposure negates risk of the autoimmune disease.

Improves bone cell health

Osteoporosis is an illness characterized by bone cell loss, leading to brittle bones that are significantly more likely to fracture during falls. Both sun exposure and D3 supplementation helps to keep bones strong and prevents loss of osteoblasts (bone building cells) due to aging.

Low 25(OH)D levels are a common risk factor for skeletal disorders, with a minimum 700 IU per day supplementation shown to prevent bone loss.

Key Point: Vitamin D3 supplementation has been shown to improve several health-related markers. This demonstrates its power as an essential vitamin.

Vitamin D Supplementation Also Improves Muscle Performance

Not only does vitamin D3 improve quality of life and various key factors in health, it also makes you a lean, mean performer in the gym and on the courts.

More and more athletes are choosing to supplement vitamin D3, even the lucky ones that get to play sports in the sun all year round. That’s because as many as 56% of athletes have insufficient serum 25(OH)D levels.

Enhanced recovery and lower muscle soreness

Muscle soreness can have a huge impact on your ability to train hard on a daily basis. After all, who fancies a leg day at the gym when your thighs are on fire and you can’t walk let alone run, due to the horrible soreness from your previous workout?

Higher doses of D3 have been shown to significantly speed up muscle repair and recovery. For example, when a group of active men were given 4,000 IU of vitamin D3 over a 28-day period, muscle soreness decreased by a huge 50%. Not only that, supplementing the sunshine vitamin also led to increased force production too.

What about vitamin D2 though?

Well, stay clear of that supplement – it’s been shown to increase muscle soreness. So it’s D3 all the way if you want to keep on top of recovery and optimize performance.

Elevates testosterone levels

The most anabolic hormone in your body is testosterone. Both men and women benefit from this naturally-occurring androgen, as it optimizes both health and physical performance.

When testosterone levels are normal, men benefit from normal testosterone production in the following ways:

  1. Enhanced muscle mass and strength
  2. High libido
  3. Lower risk of metabolic disease
  4. Lower body fat and a healthy body composition
  5. More energy
  6. Better quality of life

Females shouldn’t shy away from wanting to optimize testosterone levels either as it helps to:

  1. Improve fertility
  2. Regulate your menstrual cycle
  3. Tone muscles without bulking
  4. Increase stamina and endurance
  5. Improve health, decrease body fat and provide more energy

The problem is that more and more men and women are suffering from low testosterone levels. Women experience a significant fall in androgen hormones during the age of 20-40 and 40% of men have clinically low testosterone levels by the time they hit 45 years of age.

Vitamin D3 is a cure for low testosterone, having the natural strength to grab low T by the balls and kick start hormone production once more. Reproductive glands contain a high number of vitamin D receptors, and the association between it and T production is a significant one.

In one study, just 3,332 IU of D3 was found to increase androgen production in 165 active and healthy men with low testosterone levels. They found that supplementing D3 over a 1-year period led to increases from 10.7 nmol.L to 13.4 nmol.L for total testosterone, and 5.21 nmol.L to 6.25nmol.L for free, bioactive testosterone.

That’s a big increase!

Builds muscle mass

More muscle means more strength. Greater cross-sectional area of mass can generate more force, and strength coaches regularly aim to build athletes’ muscle tissue levels up to make them better competitors.

Supplementing vitamin D3 has become a staple practice among athletes to squeeze every last benefit out of training.

Some recent studies have highlighted that 25(OH)D levels and muscle quality are highly related. For example, one review reported that vitamin D deficiency had a negative effect on muscle strength, postural stability, muscle function and mass.

And another study, this one from the Journal of Clinical Endocrinology and Metabolism, found that a daily 2,000 IU dose of D3 resulted in a ‘positive impact on musculoskeletal parameters’, including an increase in lean mass.

Improves stamina and endurance

A key indicator of athletic ability is endurance – being able to sustain aerobic work for extended periods of time. This is important if you’re a competitive athlete, but also if you’re training to drop body fat or improve general fitness.

An interesting study on soccer players found that supplementing vitamin D3 (up to the point where 25(OH)D levels were at 118% concentration) resulted in an increase in maximum aerobic capacity of 20% – that’s huge for a group of athletes already at the peak of fitness.

Key Point: Vitamin D3 supplementation improves athletic ability. It makes you stronger, helps you recover, boosts natural testosterone production and builds unrelenting endurance.

How Much Vitamin D3 Should You Take?

Like anything, the proof is in the pudding and the devil is in the dose. In other words, a supplement is only effective if you take the right amount. Too little and you won’t feel the benefit… but too much and you can suffer serious side effects.

The good news is though, it’s actually difficult to take too much 25(OH)D.

Current government guidelines for D3 intake are 400-800 IU/day, or 10-20 micrograms. Remember though, these RDAs are set to offset deficiency not to optimize health. It’s a value based around reducing fracture rates in the elderly.

Most studies into vitamin D3 have used between 3,000-5,000 IU. That’s a safe dose that’s both well tolerated and clinically effective. It makes sense to supplement at this amount to begin with, especially if you haven’t used this kind of nutrient as a supplement before.

New research suggests mega dosing could have huge health and performance benefits

“The absence of toxicity in trials conducted in healthy adults that used vitamin D doses of 10,000 IU supports the confident selection of this value as the upper tolerable limit”.

There are several studies emerging that show super-high doses of vitamin D3 have no adverse reactions. One study in particular demonstrated that even at 10,000 IU per day, D3 was well tolerated and should in fact be made the new safety limit for the supplement.

The authors claimed that D3 toxicity was extremely rare and that larger doses above government recommendations should be advised. In fact, toxicity has only been observed in clinical trials at doses above 40, 000 IU – and even then, that’s not guaranteed.

Even patients suffering from vitamin D deficiency have been shown to tolerate doses of between 50,000-100,000 IU each day for up to 6 months without toxicity.

tl; dr ... Short and to the Point
Who is this article aimed at?
Anybody looking at supplementing with Vitamin D, or buying a combined supplement including Vitamin D. Anybody wanting details of the research into Vitamin D, and the associated health benefits.
I am busy - summarize it for me

In a nutshell: Vitamin D is extremely important for your test levels. If you live in North America or Northern Europe and work in an office there's every chance you have low Vitamin D levels.

There have been numerous quality studies done on humans establishing a firm link between Vitamin D and test, but it's hard to find one that disproves the link.