13. Vitamin D - The Facts


Vitamin D is fast becoming known as a ‘super-nutrient’. No longer just an important nutrient for healthy bones, research is now finding that deficiency of this fat-soluble vitamin can be linked to a wide range of health problems, including some of the most common chronic conditions of modern times.

What does vitamin D do?

Vitamin D contributes to numerous biological functions in the body, including:

• normal function of the immune system
• maintenance of normal muscle function
• cell division
• maintenance of normal bones
• normal utilisation of calcium and phosphorous


Vitamin D from the sun

What many people don’t realise is that very few foods naturally contain vitamin D. Fortified milk, egg yolks and oily fish are the best sources, but you certainly cannot rely on food to provide you with optimal amounts of vitamin D on a daily basis. In fact, the major source (80 – 100%) of vitamin D is actually sunshine! Vitamin D is primarily manufactured in the skin on contact with sunshine.

“Vitamin D deficiency is now recognised as a pandemic, with more than half of the world’s population currently at risk”1

UK Government guidelines published in 2009 recommended that certain groups, including children under five, pregnant and breastfeeding women, those who are not exposed to much sun and those over 65, should take a daily supplement of vitamin D. However this has since been updated with a government commissioned report published in July 2016 recommending that everybody in the UK should take a Vitamin D supplement in Autumn and Winter months.

Vitamin D deficiency

The simple answer is that we simply aren’t getting as much sun as we used to. Millions of years ago, our ancestors lived naked in the sun, spending most of the day working and travelling outside. Over the years, we have put on clothes and started working inside, travelling in cars and living in cities where buildings block the sun. In addition to this, in more recent years, skin cancer scares have further minimised sun exposure for all ages, especially for children. The recommended liberal use of high factor sunscreen has
had additional negative impacts on the skin’s natural vitamin D production process. Before the sun scare, 90% of human vitamin D stores came from skin production not dietary sources. When you look at how our lifestyles have evolved to cut out the sun’s contact with our skin, it is easy to see why we now have such epidemic proportions of vitamin D deficiency.

How much do you need?

• Recent medical research indicates that human daily requirements of vitamin D may be up to 10 x more than what is currently recommended.

• The current daily recommendation for vitamin D is 400iu. If you consider that the skin will naturally produce approximately 10,000iu vitamin D in response to 20 – 30 minutes summer sun exposure, you can easily see how 400iu might be considered too low.

• Based on information from the most current medical literature, highly respected scientist Dr Joseph Pizzorno recommends that an average daily maintenance dose of 5000iu vitamin D is more realistic to promote optimal vitamin D levels2.

• Yet scientists also agree that there is a great deal of individual variation and with vitamin D it is impossible to recommend a ‘one size fits all’ daily dosage level.

• The correct level of vitamin D is the one which results in bringing blood levels of vitamin D into an optimal range; it is essential therefore that you seek advice from your qualified health care practitioner who will be able to advise you on the best dose for your individual requirements.

What’s the best way of increasing vitamin D intake?

Since vitamin D isn’t naturally present in many foods, it isn’t easy to achieve optimal vitamin D intake from food sources alone. The risk of skin cancer from excessive sunlight or sun-bed exposure opens an important debate over spending more time in the sun to increase vitamin D levels. Therefore, most experts now agree that supplementation is currently the safest and most effective method of achieving optimal vitamin D status. Supplements should contain vitamin D in the form of vitamin D3 (cholecalciferol), since this is the form naturally produced by the skin upon exposure to sunlight and research has shown this is the most efficient form to increase vitamin D levels.3


Nutri Advanced’s Vitamin D Range

Our comprehensive range makes sure that whatever your age or personal taste, we’ve got the right vitamin D supplement for you.

Only D3, the preferred form:

We use only Vitamin D3 (cholecalciferol) the form of vitamin D produced naturally in response to sunlight.

User-friendly options:

For flexible supplementation our vitamin D is available in many forms including tablets, liquid (drops), and delicious lemon melts, which makes taking your daily vitamin D nice and easy across all ages.

Up-to-date dosages:

Many people require a higher dose than was previously thought, which is why we have a 5000iu tablet and D3 Drops (liquid) so you can dose appropriately.

No fuss, low cost:

While many supplements may contain additional nutrients, we know that vitamin D3 alone is a safe, effective way to supplement and keep the cost down.

Maintain with a multivitamin:

Our Multi Essentials range of multivitamins and minerals are perhaps the only multivitamins in the UK to provide 1000iu of vitamin D3 per tablet, making it easier to maintain a healthy daily intake of vitamin D.

Vitamin D Supplements Summary Table

Product   Vitamin D per dose   Features   Product Code
D3 Lemon Melts 2000    2000 iu (50µg)     Tasty maintainance dose   3430
D3 5000*   5000 iu (125 µg)   Higher potency for correcting deficiency    3450
Iso D3   2000 iu (50 µg)   Maintainance dose with isoflavones   44112
D3 Drops 1000   1000 iu (25µg)   Liquid for flexible dosing   3400
D3 Drops with K2   1000 iu (25µg)   Liquid D3 with Vitamin K2 as MK-7   3403


For more information on our expert formulations or any other products, please call us on freephone 0800 043 5777 / ROI 1890 987 505 (low-cost)


1. Pizzorno J. Integrative Medicine Vol. 9 No. 1 Feb/Mar 2010 ‘What have we learned about vitamin D dosing?’

2. Hall, Kimlin, Aronov et al. Journal of Nutrition. Published online ahead of print, doi: 10.3945/jn.109.115253 ‘Vitamin D intake needed to maintain target serum 25-hydroxyvitamin D concentrations in participants with low sun exposure and dark skin pigmentation is substantially higher than current recommendations’.

3. Trang HM, Cole DEC, Rubin et al. (1998) American Journal of Clinical Nutrition 68, 854-858 ‘Evidence that vitamin D3 increases serum 25-hydroxyvitamin D more efficiently than vitamin D2’.


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