Vitamin D – why it might be the only supplement you need

As the weather gets colder and Covid is still knocking around, it might be worth thinking about how to strengthen our immune systems. One way to do this is to make sure we are getting the vitamins we need. Most, like Vitamin K (see below) should be sufficiently available through a healthy diet. Vitamin D, however, is the exception.

Vitamin D

However sceptical you might be about vitamin supplements, it seems there is one exception: Vitamin D which, despite its name, is not a vitamin but a hormone that promotes the absorption of calcium, magnesium, and phosphate in our bodies. These nutrients are vital for the health of our immune system, bones, teeth and muscles. In children, Vitamin D deficiency causes rickets, where bones become soft, weak, deformed, and painful.

We mainly get Vitamin D from sunlight, fatty fish and, in smaller amounts, beef liver, cheese and egg yolk so it is not easy to get enough from our diets alone.  It is the only vitamin supplement that the NHS recommends every adult take, namely a 10-microgram supplement in autumn and winter. This has recently been extended to a recommendation of year-round supplementation in view of potentially decreased sun exposure during the lockdown. Some articles, including this one by the BBC, state that from studies:”around 20% of the UK has a profound Vitamin D deficiency.”

The benefits of Vitamin D on the immune system have long been recognised, for instance in relation to immune disorder disease multiple sclerosis. According to the Mayo Clinic research over the years has shown that maintaining adequate levels of Vitamin D may have a protective effect and lower the risk of developing multiple sclerosis (MS). A number of studies have shown that people who get more sun exposure and vitamin D in their diet have a lower risk of  MS.” It is also worth noting that MS is not found at all near the equator where sun exposure is very high.

Another key sign that you may want to consider Vitamin D supplements is constant fatigue and muscle ache. It is apparent that those that suffer from these effects, when taking Vitamin D supplements, can see benefits within five weeks of taking them. And even in the most extreme of cases, studies of cancer patients have found similar effects. Vitamin D may also help bolster and regulate the immune system by clearing bacteria.

We get considerably less sun than our ancestors used to because here in the northern hemisphere our sunlight levels are much lower than the equator, especially in winter. People nowadays are also a lot more likely to spend more time indoors on their computers or games consoles. It could benefit anyone who prefers to remain indoors to consider Vitamin D supplements.

But with so many products on the market, what kind of supplements should you take?

Nutritionist advice on Vitamin D supplements

We spoke to local nutritionist Sam Silvester who made the following suggestions.

“Vitamin D2 comes from plant sources so is cheaper to produce, and is the most common form of Vitamin D included in fortified foods. However Vitamin D3 is what our skin produces in response to sunlight and therefore what we lack most. Vitamin D3 is usually animal-based, made from lanolin washed from lambs’ wool. There is aslo a vegan source of Vitamin D3 from lichen.

“Whilst the NHS recommends 400 IU (International Units) per day in liquid or tablet form, in the winter nutritionists recommend an optimal dose of 2,000 IU per day which is 50ug (micrograms): 1 microgram of Vitamin D = 40 iu. People with darker skins may be more deficient and have a higher need during the winter. Some people with auto immune conditions may also need more.

“During the summer months this can be reduced to 400 IU per day unless you are someone who stays inside, covers up, has dark skin or uses sunscreen to cover any exposed sun.  Since Vitamin D reacts on exposed skin, just being out in the sun but covered up will not increase absorption.  If you are a sun worshipper, like me, you can stop Vitamin D in the summer unless we are unlucky to have bad weather.

“Vitamin D is excellent at helping us absorb calcium, so therefore overdosing on Vitamin D can cause a build up of calcium leading to kidney stones or calcification of the arteries or soft tissues, so do stay within the recommended optimal dose.  You can get home prick test from places such as  to test your levels of Vitamin D if you are worried that you are deficient or having too much.”

To find out more please feel free to contact:

Samantha Silvester MBANT CNHC, Registered Nutritional Therapist
07767 260 374

Vitamin K

People are also curious about Vitamin K which, according to the NHS, Vitamin K is a group of vitamins that the body needs for blood clotting, helping wounds to heal.There’s also some evidence vitamin K may help keep bones healthy.Vitamin K is found in green leafy vegetables – such as broccoli and spinach, vegetable oils, cereal grains and small amounts can also be found in meat and dairy foods.Adults need approximately 1 microgram a day of vitamin K for each kilogram of their body weight.For example, someone who weighs 65kg would need 65 micrograms a day of vitamin K, while a person who weighs 75kg would need 75 micrograms a day. A microgram is 1,000 times smaller than a milligram (mg). The word microgram is sometimes written with the Greek symbol μ followed by the letter g (μg).You should be able to get all the vitamin K you need by eating a varied and balanced diet. Any vitamin K your body does not need immediately is stored in the liver for future use, so you do not need it in your diet every day.

A google search will bring up a lot more information, for instance lists many benefits of Vitamin K including immune and digestion boosting.

Photo credit: Liam Heisig


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