Vitamin D: A guide to getting enough

The UK hasn't exactly been bathed in sunshine of late, and national surveys estimate that up to a fifth of the UK population is deficient in vitamin D, aka, the ‘sunshine’ vitamin. The high level to which we’re lacking in the vitamin has  led to suggestions that everyone should be supplementing their diets  to ensure a healthy uptake of the key vit, with the government debating last year whether official advice should be extended beyond at-risk groups.

Professor Mike Kelly, Director of the NICE Centre for Public Health , paints a picture of where the nation’s vitamin D markers are at:

“Around 10 million people in England may have low vitamin D status and so could be at risk of health problems, and they may not know it. People with darker skin are particularly at risk; during winter months nearly 75% of adults from Asian or African and Caribbean backgrounds may have low vitamin D levels. People who are over 65 years old are another group at risk of having low vitamin D levels, and so are also at risk of conditions like osteomalacia (soft bones). NICE recommends making low cost vitamin D supplements widely available to people at risk of deficiency.”

It’s not just our bones that benefit from harmonious vitamin D levels, as pharmacist and co-founder of  Victoria Health Shabir Daya  highlights:

“An amazing amount of research has and is still being carried out on this vital vitamin. We now know that vitamin D has a role well beyond that of being concerned with calcium absorption and bone growth. We also know that vitamin D receptors have been found in over 50 organs and sites within the body, which means that the body’s requirements are greater than we initially thought.

"Recent studies indicate that vitamin D deficiency may be linked to a variety of chronic health concerns including optimal immune function, diabetes, depression and even cell mutation.”

Making it on our own

It appears that the impact of vitamin D is more far reaching than we might have imagined; in fact, due to the unique manner by which we ‘make it’, even defining it as a vitamin isn’t entirely accurate, as Shabir explains:

“Vitamin D is not strictly a vitamin. A vitamin is a compound that cannot be produced by the body and since vitamin D is produced in the skin as a result of exposure to sunlight, this is why vitamin D is more accurately described as a hormone.

“Although we are capable of producing vitamin D, we rarely manufacture sufficient levels due to the latitude we live in. Small amounts of vitamin D are found in fortified foods including milk, cereals, oily fish and juices but this amount is too small to make any significant difference. In fact it is estimated that we would need to drink 20 glasses of milk every day to maintain optimal levels of vitamin D.”

Supplement science

Clearly chugging gallons of the white stuff isn’t an option to maintain superlative vitamin D levels, so what’s the solution when it comes to getting our daily quota? Rather than necessarily relying on occasional sunshine or swallowing pills, Shabir thinks that vitamin D delivery via a topical spray may be the way forward:

“A healthy and balanced diet can at the maximum supply us with 10% of the recommended daily amount and actually for the majority, our diets only supply us with 5% of the recommended daily amounts, leaving a 95% deficiency of vitamin D in our bloodstream.

“Bearing in mind this shortfall, can we really afford not to take vitamin D supplements? The simple answer is no, and I would recommend that adults take DLux 3000 Spray , £7.95, by Better You during the winter months and perhaps change to  DLux 1000 Spray , £7.15, during the summer months. The reason for using this supplement is that taking an oral spray allows for this vitamin to be absorbed sublingually into the bloodstream, avoiding the gastrointestinal route which always results in lesser absorption of any nutrient.”

Spritzing rather than ingesting has been proven to enhance our assimilation of vitamin D;  Better You reported in 2016 that trials by the National Technical University of Athens and Swiss Research Centre Pharmabase found that absorption of of vitamin D via an oral spray was at least 50% faster and more effective than via traditional tablets or capsules. That being said, unless you’re in the group of 1 in 5 UK adults with a deficiency, putting away extra vitamin D willy nilly may not in fact be necessary, especially considering that only 8% of adults between the ages of 19-64 are lacking in vitamin D during the summer months according to NICE research.

Too much of a good thing

Genetic epidemiologist Professor Tim Spector  is in the devil’s advocate camp regarding overdosing on vitamin D, arguing in his book The Diet Myth  that vitamin D is not the cure-all that it’s been hailed to be:

“Vitamin D is always in the news as it comes mainly from sunshine and to a lesser extent from diet in the form of oily fish, eggs, dairy and some mushrooms. Low levels of vitamin D are consistently associated by our old friend the observational study with an increased risk of over a dozen common diseases, including heart disease, high blood pressure, cancer, fibromyalgia, autoimmune disease and MS, as well as with depression and early death.

“With the possible exception of heart disease and MS, these claims are likely to be spurious, and I admit to having published some of those studies myself. Surveys of vitamin D levels across populations often report that a third are deficient. This has led to its being recommended as a supplement in a wide variety of situations as if it were a global panacea.”

Professor Spector quotes three randomised trials in which high levels of vitamin D (40,000 to 60,000 units a month rather than the 30,000 recommended) were found to be dangerous rather than protective, with those on high doses of vitamin D experiencing more fractures and falls than those with lower levels of vitamin D in their blood.

It seems that flooding our bodies with vitamin D by swallowing supplements could do more harm than good, and the jury’s still out on how we react to a sudden influx of artificial nutrients, as Dr Spector emphasises. “We know very little about the interactions between our gut microbes and vitamins, especially in mega-doses.”

If you are deficient (your GP can assess your levels by carrying out a blood test) , Dr Spector doesn’t strictly advocate throwing away the supplements, but addressing the root cause of a vitamin D deficit is key in addressing any imbalance:

“Unless you have major deficiency symptoms and really, really low levels try to avoid artificial supplements and use sunshine and food instead. Some of the low vitamin levels we are seeing in modern populations, rather than causing disease, may be markers for generally poor nutrition or a lack of outdoor activities.

“We have now placed our trust in doctors and vitamin tablets rather than in natural alternatives like oily fish or the sun, which are usually the better option. The sensible advice if you want to reverse a vitamin D deficiency is to sit in the sun for ten or fifteen minutes a day, exposing just your face and arms, or in winter to eat oily fish.”

Adjusting our lifestyles to promote better vitamin D absorption will maximise our chances of getting within the healthy range, and if once you’ve made possible changes you’re still not seeing an improvement in your D status,  then call in the supplement cavalry (preferably in a spray form as above). Slow and steady wins the race once again it seems, at least until we know more about how large doses of chemical vitamins affect our metabolism and overall health.

Here are 10 things you may not know about vitamin D

The Diet Myth: The Real Science Behind What We Eat  by Tim Spector is published by W&N in paperback

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