Vitamin D is a fat-soluble vitamin. This means it dissolves in fats and oil and can be stored in the body for a long time. It’s very important for your overall health, especially bone health.
Vitamin D helps to control how much phosphate* and calcium* you absorb from food. Having the correct amount of vitamin D, calcium and phosphorus is important to maintain healthy, strong bones. Naturally vitamin D can be produced by the skin when it is exposed to sunlight. Often, we’re not exposed for long enough to receive the required amount, plus it isn’t always safe to stay out in the sun for too long. That’s why it’s important to eat certain foods and supplements to ensure the adequate level is achieved in your blood.
Two forms of dietary vitamin D exist:
Vitamin D3. Found in some animal foods and egg yolks.
Vitamin D2. Naturally found in various plants.
D3 is said to be more efficient than D2 and healthcare professionals generally recommend D3 supplements. That’s because it can help to raise the overall level of vitamin D and the longevity of it is longer than D2.
Over the years there has been various debates on how much vitamin D you are required for optimal functioning. Factors such as age, sun exposure, latitude and many more can determine how much vitamin D you need. The National Institutes of Health (NIH) recommends an average daily intake of 10-20 micrograms. However, if your skin exposure to sun is infrequent, you may need more.
Where can it be found?
The main sources are:
- Foods such as fatty fish (salmon, tuna, sardines and fish liver oils), egg yolks, beef liver
What can it do?
Besides from maintaining your bone and teeth health, vitamin D has numerous other benefits:
- Help fight disease – Research conducted in 2018 has shown that it can reduce the risk of multiple sclerosis (MS). Low levels of vitamin D had a direct correlation with an increased risk of MS.
- Support Immune Health – Having inadequate levels of vitamin D might lead to risk of infections and illnesses because of weakened immune health.
- Muscle Strength – Research has shown that taking 700 to 1000 IU of the vitamin a day lowered the risk of falls by 19% but taking less did not offer such protection. Building strength in the muscles creates stability, leading to less accidents and falls in the older generations. 
- Type 1 Diabetes – Whilst this may be genetic related, there are studies where research has shown that a child in Finland is 400 times more likely to develop type 1 diabetes than a child in Venezuela, due to the lack of sun exposure. Likewise in young adults, individuals with high levels of vitamin D had a 44% lower risk of developing diabetes in adulthood than those with lower levels.
- Flu and Common Cold – Making its way through many households in the winter months, a pesty cold may arise due to the lack of vitamin D and warm sunshine in the sky. Research suggests that children who have vitamin D deficiency are more likely to have respiratory infections. 
Vitamin D and Covid-19
Throughout the pandemic various holistic treatments and supplements that may not generically be considered as ‘treatment’ have come to the surface for providing relief and support to various symptoms and illnesses. The National Institute for Health and Care Excellence, Public Health England and the Scientific Advisory Committee on Nutrition concluded that there is good evidence on vitamin D protecting against respiratory infections. It is recommended that vitamin D intake between October and March should be approximately 400 IU to optimise musculoskeletal health .
*Phosphate – is a mineral that plays an essential part in many functions of the body, including teeth, bones, muscles and nerves.
*Calcium – This mineral supports the structure and function of bones and teeth.
 – https://www.bmj.com/content/339/bmj.b3692.long
 – cambridge.org/core/journals/epidemiology-and-infection/article/epidemic-influenza-and-vitamin-d/C4D90C6E7CB127E6DF7A52D3A9EE2974