For those of us in the northern hemisphere, the days are getting shorter, the temperature is falling rapidly and unfortunately the challenges our bodies face will only get tougher from here.

As active people and athletes, we all know just how important and beneficial exercise and the great outdoors can be for everyone’s physical and mental health. But as winter sets in and even for the most dedicated fitness fanatics, getting outside in the cold and wet just doesn't seem so appealing and so, you guessed it… we all creep back indoors.

One of the easiest things we can do to optimise our health and performance this winter is with Vitamin D, The Sunshine Vitamin.

Ensuring we get adequate vitamin D into our diet is crucial for both our overall health and performance. It has been well known for years that vitamin D is necessary for both bone and skeletal health. Emerging research, however, also indicates the vital role of vitamin D in a whole host of body systems and for non-skeletal functions including: skeletal muscle function and growth, immune function, inflammatory modulation, and athletic performance.

Several different types of cells in the body, including immune cells, contain the receptor for Vitamin D, which means they can respond to Vitamin D molecules, triggering different reactions in the body.

No wonder Vitamin D can affect so many aspects of health including bone health, cardiovascular health, immunity, autoimmune disease, type I diabetes, and mental health.

So why is it called the ‘Sunshine Vitamin’?

Quite simply, it is called the ‘sunshine vitamin’ because it is usually produced by the body in response to direct sunlight. When our skin is exposed to sunlight, it makes vitamin D from cholesterol. The sun’s ultraviolet B (UVB) rays hit cholesterol in the skin cells, providing the required energy for vitamin D synthesis to occur.

Although classified as a vitamin, D3 cleverly transforms into a hormone in the body and circulates in the bloodstream which is why it is able to play a role in a variety of body systems. For example, vitamin D helps in the absorption of calcium and phosphorous which is perhaps its most vital function.

How does the body produce it naturally?

During the sunnier months in the northern hemisphere (April to September) getting adequate sun exposure and therefore vitamin D production can be quite easy to achieve and many studies have shown that midday, especially during summer, is the best time to get sunlight.

At noon, the sun is at its highest point, and its UVB rays are most intense. That means you need less time in the sun to make sufficient Vitamin D. Our bodies are also at their most efficient at making Vitamin D at noon. For example, in the UK, 13 minutes of midday sunlight exposure during the summer, three times per week is enough to maintain healthy levels.

But we’re not in the summer right now. And unfortunately as we move through autumn and into winter, we are exposed to less and less natural daylight and when the sun does shine, it is far too cold for us to expose enough skin to allow the natural production of vitamin D.

But it isn’t darker days that limit our vitamin D levels. Many factors can affect your ability to get sufficient amounts of vitamin D through the sun alone. These factors include: being in an area with high pollution, using sunscreen, spending more time indoors, living in big cities where buildings block sunlight or having darker skin (the higher the levels of melanin, the less vitamin D the skin can absorb).

How much vitamin D do I need every day?

During the sunnier months we are generally able to produce sufficient quantities naturally through exposure to direct sunlight. However, it is becoming more and more apparent that western populations are generally vitamin D deficient so supplementation is recommended to top up those vitamin D levels.

Here at U Perform we follow the science and current recommendations for daily vitamin D supplementation sit at 4000IU per day. Can you take more? Yes, you can. But 4000IU is the optimal amount per day due to the bioavailability of vitamin D at the gut.

Can you get vitamin D from foods?

Only handful of foods contain significant amounts of vitamin D. These include cod liver oil, swordfish, salmon, tinned tuna, beef liver, egg yolks, and sardines. That said, you would need to eat them nearly every day to get enough vitamin D which is why supplements are recommended to help us get enough vitamin D per day.

Getting sufficient Vitamin D contributes to the healthy function of our immune systems, improving resistance against certain diseases. It also plays a role in the process of cell division as well as ensuring the maintenance of healthy bones, teeth and muscles. It’s for those reasons and more that we have included Vitamin D3 in the U Perform product range. Daily supplementation of vitamin D (especially during the winter months) is such a simple and cost effective way to support your body’s health and performance.

And for this month only, we have a very special offer just for our U Perform family. To make sure you have got your vitamin D sorted right the way through to Christmas, we are offering 3 for the price of 2 on our Active Vitamin D3.