Including why taking a vitamin D supplement may be more important than ever in the time of Covid-19

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Even before the pandemic, the government suggested that everyone should supplement their diets with vitamin D but a recent report in the British Medical Journal  calling for more investigation into the link between a deficiency with coronavirus survival rates could mean that it's more important than ever to keep levels topped up.

The report's authors suggest that "Vitamin D deficiency is a likely factor in the progression, and/ or severity, and/ or mortality of COVID-19," and that vitamin D supplementation may present clinical treatment opportunities. It's also been reported that Public Health England  will advise this week that everyone should supplement 10µg vitamin D daily during the lockdown period, not just in the winter months.

The BMJ itself, in a recent  statement,  singled out vitamin D in its call for the recognition of the role of good nutrition in the time of Covid-19. "Vitamin D3 is produced in the skin and plays a key role in the immune systems, the highly complex mechanisms in the body that are designed to help protect people against a host of infectious agents, including bacteria and viruses," it said. "People who are self-isolating or unable to go outside into the sunshine, people living in regions impacted by air pollution, people who are malnourished, overweight or obese and those with low baseline 25(OH)D [a vitamin D biomarker] concentrations are likely to have weakened immune systems and functions and be at increased risk of viral infections."

It went on to say that we should all be taking vitamin D to reduce the spread and effects of the disease. "In times of emergency, public health measures to reduce risks of infections and death should include messages about the role and benefits of the essential micronutrients for the immune system. Their contribution to the resilience of the population to the Covid-19 pandemic, particularly vitamin D supplementation to raise 25(OH)D to optimal serum levels, should have higher priority for both patients, all medical and care home staff as well as the general population."

Immunity expert Dr Jenna Macciochi, of the University of Sussex, told The Sun : “If you are deficient in Vitamin D, you are three to four times more likely to catch a cold. It, therefore, makes sense a viral respiratory infection like Covid-19 would be worse if you were vitamin D deficient.”

A daily ten minutes in the sun gives us adequate amounts of vitamin D, but even that can be difficult to achieve at times especially when we're having to stay inside in lockdown most of the time at the moment; we can't solely blame lockdown for our deficiency though; the impact of vitamin D and even the factors affecting how much we’re getting, are far-ranging. Here are some more things you may not know about this vitamin D.

1. We make our own vitamin D

Akin to squirrels, our skin stores vitamin D away for the winter, having ideally been exposed to sufficient UVB rays during the summer months in order for receptors in our skin to synthesise the light to make vitamin D. Trouble is, the further you travel from the equator, the less vitamin D we’re making. We’re at our lowest ebbs in the northern hemisphere from November to March, when we’re reliant on food sources (more on those later) and what we’ve built up already, which, if you’ve experienced a British “summer”, may not be too abundant. Hence the reason that the  National Institute for Health and Care Excellence  (NICE) is recommending that the government promote vitamin D supplementation amongst the entire UK population, as a public health measure. It’s up for consultation this month, so we’ll keep you posted.

2. The recommended daily amount (RDA) guidelines are vague

While at-risk groups, for example, pregnant and breastfeeding women, those over the age of 65 and those with limited sun exposure are advised to supplement their diets with 10 micrograms of vitamin D a day (7 mcg for babies from 6 months onwards until the age of 5), the daily diet of the average UK woman provides just 2.8mcg of vitamin D, and 3.7mcg for men, according to the National Diet and Nutrition Surveys.

It’s tricky to get enough vitamin D through diet alone, but the richest sources are oily fish, eggs, yoghurt and cheese - which explains why vegans are often deficient in vitamin D. Given that the guidelines were only updated recently to suggest children over 5 and adults should consider taking daily supplements containing 10mcg of vitamin D, it’s not surprising that many adults are down on D. Fortified cereals, dairy products and spreads can be of benefit, but Britain’s a bit behind in that regard…

3. Unlike abroad, we’re not big on fortifying our foods

In countries such as Canada it’s mandatory for all dairy milk to be fortified with vitamin D to keep general levels up, but that’s not so for the UK. One basic, however, is beginning to get higher D status…

4. ...Although you might find vitamin D it bread

Bread itself doesn’t boast a lot of vitamin D, but good old  M&S  became the first UK retailer to enrich all packaged bread and bread rolls on its shelves with vitamin D. The range contains yeast that has been exposed to UV light in order to naturally elevate its vitamin D content, and two slices will bump up your levels by 15%. The move was supported by M&S customers, as 78% of 2476 shoppers welcomed vitamin D fortification, mainly because they suspected they weren’t getting enough of the bone boosting vitamin. Fewer tablets and more toast are appealing to us to too.

5. A little fat helps vitamin D to function

If you’ve ever felt guilty about blobbing butter on a holier than thou plate of vegetables, stop right there. The days of plain, boiled to death broccoli and the like are numbered, as they’re neither tasty, nor as it turns out, actually optimally nutritious. Follow dermatologist  Dr Stefanie Williams ’ lead on this one:

“To increase your sense of satisfaction and fullness, you can always slather your vegetables in extra virgin olive oil or even some butter. Adding oil is also important for the resorption of fat-soluble vitamins A, D, E and K. Also, adding some pine nuts or flaked almonds will greatly enhance many vegetables.”

We love a touch of  Vita Coco Coconut Oil  on our carrots too, and such delicious facilitators of vitamin D might even convince veg dodgers to get involved.

6. Vitamin D could help your kids' muscles

The conversation around children and vitamin D normally revolves around the avoidance of rickets, and while that’s a crucial priority, other benefits of high vitamin D uptake for kids aren’t so widely discussed. Research published in  Endocrine Research  linked high levels of maternal vitamin D to better muscle development in children. The study involving 678 children correlated vitamin D levels in the womb with grip strength at the age of four, finding that high levels of vitamin D in late pregnancy meant that children were more likely to have greater muscle strength in their hands at the age of four.

The good news doesn’t stop there either, as the team at the University of Southampton predict that strong muscle fibres at this age could result in more muscle mass and fewer falls and fractures into adulthood and later life. The trials continue, but if you’re keen to mother a superhero, don’t neglect your vitamin D supplements.

7. You're likely getting less vitamin D if you live in the city

If you’re an urban dweller, chances are you’re getting less vitamin D on a daily basis than those living in a rural idyll, mainly thanks to sun-blocking skyscrapers and high rises and increased levels of pollution. Chances are you work in an office too, and if your job involves regular night shifts, you’ll be even more susceptible to vitamin D deficiency. It doesn’t matter how virtuously you live either; indoor athletes such as gymnasts are thought to be especially lacking in vitamin D. Escape to the country once in a while, book a beach break and in the meantime top up your supply with  Inner Me Essential Three , which will handily also help you to keep your omega-3 and probiotic levels peaking (even the dedicated healthistas amongst us need help on these three counts).

8. Vitamin D deficiency has been linked to dementia and MS

The association between a lack of vitamin D and osteoporosis is well known, but recent studies suggest that vitamin D deficiency may also be implicated in other diseases, such as multiple sclerosis and dementia.

A large study published last month  PLoS Medicine  suggested that those genetically inclined to lower blood levels of vitamin D were more likely to suffer from MS than those who didn’t possess the same genetic predisposition, leading experts to go on to now investigate whether vitamin D supplementation could improve the lives of those with MS, or even prevent it in the first place. While the findings were far from definitive, it’s interesting to note that MS is more common in countries far from the equator.

In the case of dementia, we now know that experts predict that one in three of those born this year will become sufferers, while a study published last summer in  Neurology  indicated that those with severe vitamin D deficiencies were more likely to develop dementia. Researchers at the University of Exeter Medical School looked at data from 1650 people over the age of 65 and found that while 1169 of those observed had good levels of vitamin D and a one in 10 chance of developing dementia, 70 of the participants had serious deficiencies and a one in five risks of developing the disease. Dr David Llewellyn, who led the research, admitted to the BBC that ‘the results were surprising- we actually found the association was twice as strong as we anticipated’. It’s too early to tell if the link is certain, but it’s a study worth bearing in mind if supplementation is on the cards.

9. A little extra vitamin D could save your skin

...If you suffer from psoriasis that is. In  The Clear Skin Cookbook , nutritionist Dale Pinnock states his case:

“There is some evidence that vitamin D may be useful in the treatment and management of psoriasis. Skin cells have receptors for the active form of vitamin D (after it has been converted in the body), and vitamin D regulates the turnover of skin cells. As psoriasis is an over-accelerated turnover of skin cells, extra intake of this nutrient may well prove beneficial.”

10. You can have too much vitamin D...

While many of us are D deficient, you can overdo it. According to the NHS, you could end up doing more harm than good if you regularly exceed the dosage in your daily supplement:

“Taking too many vitamin D supplements over a long period of time can cause more calcium to be absorbed than can be excreted. The excess calcium can be deposited in and damage the kidneys. Excessive intake of vitamin D can also encourage calcium to be removed from bones, which can soften and weaken them.” As always, moderation wins out.

MORE GLOSS: Why you need more vitamin D