Your body requires a number of essential nutrients to function effectively on a daily basis -- and none are more important than Vitamin D. This potent vitamin plays a myriad of roles in the human body, ultimately making sure that you are at the top of your game all the time.
More importantly, supplementing with larger amounts of Vitamin D can also have some serious effects on your health and function -- which is what I want to talk about today.
What is Vitamin D?
Vitamin D is a fat soluble vitamin that your body needs to survive.
It is most commonly considered for its role in the production of new bone tissue. In this manner, it helps you absorb calcium from the food you eat (which is used to build new bone), while also assisting in the layering of new bone.
As a result, if you don't eat enough Vitamin D, then your bones can become brittle and prone to fracture.
This unique vitamin also supports immune system function, and is involved in numerous physiological processes throughout the human body -- which is why some researchers actually consider it to be a type of hormone.
Although Vitamin D can be found in foods like fish and seafood, your body also makes it when it is exposed to light from the sun. As a result, getting regular sun exposure offers a suitable way to keep vitamin D levels in normal ranges for most of the population.
I should also note that there is reason to believe that the majority of the population are actually deficient in Vitamin D, which makes supplementation imperative. Furthermore, there is some evidence suggesting that supplementing with higher doses of vitamin D can offer additional benefits -- which is what we cover in this next section.
What are the benefits of Vitamin D?
Vitamin D is arguably the most important nutrient in the human body -- which is why its supplementation can offer so much benefit.
1. Stronger Bones
As I indicated above, Vitamin D is important for bone health. More specifically, it ensures you have adequate levels of calcium and phosphorus in your body by facilitating their absorption in your digestive tract.
As you may already know, these two compounds are used in the production of new bony tissue, as well as in the repair of damaged bone. Very simply, supplementing with Vitamin D improves the availability of these compounds, which increases bone growth.
This can increase bone mineral density, helps prevent the onset of osteoporosis, and may even reduce the risk of bone injuries from occurring .
2. Boosts Weight Loss
One of the more surprising benefits of Vitamin D supplements relates to weight loss -- or more specifically, fat loss.
A recent study explored the effect of Vitamin D on fat loss by putting a bunch of overweight men and women on a weight loss regime. While they both underwent the same program, half also received a Vitamin D supplement, while the other half did not.
As you may have guessed, the group receiving the Vitamin D supplement lost more fat mass than the group who did not, even though they were following the same diet and exercise regime .
3. Enhances Mood
Early on in this article I alluded to the fact that some researchers consider Vitamin D to be a hormone. Well, this is because it impacts numerous areas of the human body -- even areas related to mood and emotional control.
In fact, research has shown that the supplementation of Vitamin D can improve emotional wellbeing, while simultaneously reducing feelings of depression and anxiety .
While I would argue that having an improved mood will help you get more out of your training, more important is the fact that feeling happier in your day to day life is never a bad thing -- and Vitamin D can help.
4. Increase Muscle Strength
Amazingly, Vitamin D supplements have even been shown to improve strength and power.
A systematic review of over 30 studies found that the supplementation of Vitamin D can cause acute increases in muscle strength and power . This ultimately means more reps per set, or more weight on the bar.
While this is unquestionably cool in the short term (I mean, instant strength, right?), over the duration of a longer term training block this is likely to lead to greater improvements in strength and size -- which is pretty amazing if you ask me.
5. Faster Recovery
In conjunction with its ability to promote muscle strength and power, Vitamin D is also important for recovery.
See, after a strenuous bout of exercise your body uses Vitamin D to increase the activity of muscle cells. Within this, it also downregulates something called myostatin, a unique protein molecule that blunts muscle protein synthesis.
With this in mind, taking Vitamin D supplements has been shown to increase recovery after heavy resistance exercise  -- and as you know, when it comes to growing muscle, recovery is arguably the most important factor.
In short, when you train in the gym you place your body under stress and break down your muscle tissue. This is what tells your body that it needs to grow bigger and stronger -- a process that can only occur if you are recovering effectively.
All of which means that Vitamin D can increase your ability to recover, all while enhancing the results of your training.
6. More Testosterone
Incredibly, Vitamin D also plays a role in the production and secretion of testosterone.
While the exact mechanism remains somewhat unclear, a recent research study demonstrated that supplementing with Vitamin D for a 12 month period can cause vast improvement in free testosterone levels .
Given that testosterone is the most anabolic hormone in your body, this has obvious implications for muscle growth.
7. Improved Sleep
Lastly, taking Vitamin D has also been shown to have a profound impact on sleep.
Taking a high dose Vitamin D supplement for as little as 8 weeks has been shown to cause significant improvements in sleep quality. With this also comes the ability to fall asleep faster, combined with longer sleep durations .
Given that sleep is your body's most important recovery mechanism, this can have a marked improvement on the results of your training.
Optimal Vitamin D Dosage
Now, this is where things get a little bit tricky. See, it is well known that Vitamin D is important for health and function -- and as a result, there are already guidelines in place regarding its recommended intake.
These guidelines suggest that consuming up to 800 IU of vitamin D per day will meet the needs of 97% of the population, while ensuring they do not develop a deficiency. However, several of the studies discussed above used doses of up to 4000 IU.
Moreover, research exploring the health benefits of Vitamin D supplements have shown that taking between 1000 and 4000 IU per day leads to better health outcomes than the recommended 800 IU per day .
This would suggest that if you want to get the most out of your Vitamin D supplementation, opting for a dosage of between 2000 and 4000 IU is probably going to be your best bet. But, as this is above the recommended daily intake, you should seek advice from a medical professional before taking.
Take Home Message
Vitamin D is arguably the most bang-for-your-buck supplement on the planet.
With the ability to improve strength and power, enhance post exercise recovery and sleep quality, boost mood and fat loss, and increase testosterone levels and bone density, it literally does everything.
So, if you are after a complete and utter game changer, then look no further.
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