Do I really need Vitamin D? A complete guide

In this article, Jenny Carson, senior nutritionist at ethical vitamin company Viridian Nutrition offers a complete guide to all you need to know about Vitamin D.

Why do I really need Vitamin D?

When we ask ourselves, "Do I really need Vitamin D," we first need to look at the benefits it gives us.

Our skin naturally produces vitamin D when it’s exposed to sunlight in the summer months, which is why it’s known as the ‘sunshine vitamin’.

This highly important nutrient helps to prevent an array of health issues and has multiple health benefits.  Among them:

• Maintaining the health of our bones and teeth
• Maintaining healthy muscle function
• Keeping our immune system strong
• Normal absorption and utilisation of calcium and phosphorus – which are needed for good bone health
• Normal blood calcium levels – an important marker against the risk of arterial plaque build-up.

Can vitamin D benefit me during perimenopause and menopause?

If you are a woman in your 40s, 50s, 60s, and upwards, there are many benefits of vitamin D. It can help to reduce symptoms of perimenopause and menopause, such as low mood and muscle aches.

Because this vitamin helps with the absorption of calcium, it can also help with the loss of bone minerals in post-menopausal women – particularly important to maintain good bone health and if you are at risk of osteoporosis. 

Related: Top 5 nutrients for perimenopause and menopause

What’s the best way to boost my Vitamin D levels?

Get outside when you can! The best and most efficient natural source is through controlled sun exposure. This can range from 20 minutes for those with fair skin to 40 minutes daily for those with darker skin.

Our bodies know how much we need – so once stores are fulfilled by sun exposure, the mechanism stops. This avoids your levels from getting too high and causing issues within your body (known as toxicity).

Those with fair skin require the shortest time in the sun, while those with darker skin will need the longer recommendation before covering up or using SPF.

Why do so many people have vitamin D deficiencies?

Deficiency is becoming more and more common. It is due to the winter months and a range of lifestyle factors - such as increased time spent indoors, fears of sun overexposure, use of sunscreen and wearing clothing that covers the legs and arms.

The classic deficiency is rickets and is becoming increasingly common in the UK. Hospital admissions for vitamin D deficiency and/or rickets have increased by 30% year on year. Fortunately, there are ways you can safeguard against deficiency through dietary supplements.

Am I at risk of low vitamin D?

Those at risk are the elderly and small children; however, in addition, those with darker skin and those whose skin is not exposed to the sun.

Historically, Public Health England vitamin D recommendations were solely for the elderly and children. However, in response to the widespread inadequate vitamin D status, the recommendation to supplement 400IU of vitamin D in winter months was extended to all UK residents.

Can I get vitamin D from food?

Very few foods contain this vitamin: dietary sources include eggs, milk and fatty fish, albeit at potentially insufficient levels. Instead, it is often fortified into foods, for example, into milk alternatives, and this is why a daily supplement is still required between October and March.

What’s the Government recommendation for intake?

Public Health England (PHE) recommends that all adults and children would benefit from 400IU of vitamin D from October to March. Larger doses may be necessary if you've been diagnosed with a deficiency.

How much vitamin D should I take?

You’ll notice that measurements appear as ‘IU’ – this stands for International Units. You may also see micrograms (mcg) or µg being expressed. As a guide, 400IU = 10 micrograms or 10 mcg, 10µg, and this is the nominal amount recommended by Public Health England.

There are many factors which can determine how much vitamin D you need as an individual. These include age, season, skin colour, sun exposure, clothing, use of topical moisturisers with an SPF rating and more. Different research studies recommend different amounts of vitamin D intake.

• Public Health England recommends that everyone should take 400IU of Vitamin D daily
• Adults, the elderly and pregnant women can take up to 1,500-2,000IU daily if recommended to do so by their Healthcare Professional.
  (Endocrine Society Guidelines on Vitamin D define the amount based on healthy blood levels.)
• Infants (0 to 1 year) should be given 400IU daily
• Children (1 to 12 years)should take 400IU daily

Vitamins are either water-soluble or fat-soluble. Vitamin D is fat soluble – which means it’s best absorbed with foods containing fat.

Is it possible to take too much vitamin D?

Fortunately, this would be very hard to do. When regularly taking vitamin D3 as a supplement, 400IU-2000IU is considered well-tolerated and safe.

It is very difficult to achieve vitamin D toxicity, which is defined at blood levels greater than 150ng/mL.

How will I know if I have a vitamin D deficiency?

The best way to accurately measure is with a blood test; this can be done with your GP or privately.

Once the results are processed, your GP will make a recommendation for supplements if it is found that your levels are too low. Generally, a measure of less than 50ng/ml in your blood test would suggest you’ll need to improve your vitamin D levels (with nanogram per millilitre of blood being the standard measure for these tests).  That’s why you’ll notice some vitamin D3 food supplements provide 1000IU or 2000IU.

What is the difference between vitamin D2 and D3?

There are two major forms of vitamin D – D2 and D3

• Most vitamin D3 is animal derived – mostly from Lanolin in sheep’s wool. The exception to this is Vitamin D3 derived from Lichen. Vitamin D3 is transformed into the active form of vitamin D quicker than vitamin D2.
• Vitamin D2 is sourced from plants, with levels of D2 especially rich in mushrooms. Vitamin D2 can also be produced in an organic form, available using UV-exposed organic mushrooms.

Bonus fact: mushrooms, similar to humans, make vitamin D when exposed to summer sunshine.

Is all vitamin D vegan?

No, most are derived from the lanolin in sheep’s wool and so is unsuitable for vegans or those avoiding animal products.

However, the good news is that a vegan form is available - a recent discovery revealed vitamin D3 is present in lichen, resulting in vegan vitamin D3 food supplements.

What’s the best way of increasing absorption in the body?

Vitamin D is a fat-soluble vitamin, which means it is better absorbed in the body when taken with a meal that contains fats. Therefore the best way to take it is with your meal.

What should I look for in supplements?

Read the label to ensure the supplement contains 100% active ingredients; this means a food supplement that is free from bulking agents, additives and fillers. 

For liquid vitamin D, ensure that the carrier is an oil and that it does not contain added sugar.

Finally, choose an appropriate amount, one that provides a minimum of 400IU per serving. 

A good starting place is to visit your local independent health food store, which has knowledgeable and experienced staff.

RELATED: Demystifying supplements for your 40s, 50s and beyond

Author: Jenny Carson, MRes, BSc (Hons), is a Senior Nutritionist at ethical vitamin company Viridian Nutrition. She has over 5 years of experience supporting people with nutritional health advice. She recently completed a Master of Research(MRes) in Public Health, giving her a wide understanding of public health nutrition. Her other focus areas include ageing, dealing with stress, peri and post-menopause, detox and mood.

This article has been published in a paid partnership with Viridian Nutrition. For more information visit www.viridian-nutrition.com

This article is for information purposes and does not refer to any individual products. The information contained in this article is not intended to treat, diagnose or replace the advice of a health practitioner. Please consult a qualified health practitioner if you have a pre-existing health condition or are currently taking medication. Food supplements should not be used as a substitute for a varied and balanced diet.