New government advice urges everyone to take vitamin D supplements this winter. With a deficiency linked to everything from bone disease to asthma, you could give yourself a health boost by topping up on the sunshine nutrient
This summer the government, via Public Health England, published new recommendations that people should supplement their vitamin D intake to protect bone and muscle health.
According to the Scientific Advisory Committee on Nutrition (SACN), the nature of the UK’s winters means one in five Britons have insufficient levels of vitamin D – the famed ‘sunshine nutrient’.
The great British summer is hardly tropical but, together with spring, it should provide us with most of the vitamin D needed for six months.
But, with SACN unable to say how much is made in the skin through exposure to sunlight, the government currently recommends we take 10 micrograms a day during autumn and winter to ensure our bones, teeth and muscles stay healthy. If your working day means your only fresh air comes shuffling between home, office and train, you could be at risk.
Sadly, your morning run also won’t cut it at this time of year. “Most people in the UK are at risk of vitamin D inefficiency,” says vitamin D expert Adrian Martineau, professor of respiratory infection at Barts and the London School of Medicine and Dentistry. “Even if you spend lots of time outdoors during autumn and winter, the UBV [ultraviolet B radiation] isn’t enough to make vitamin D on your skin.”
Our bodies need vitamin D to absorb calcium and phosphate – the minerals essential for maintaining healthy bones and teeth. A deficiency can cause bone diseases such as osteomalacia – known as rickets in children.
Rickets (symptoms: bow legs and skeletal deformities) might be more commonly associated with malnourished Dickensian characters, but a 2012 study found that cases had quadrupled in the previous 15 years. And it’s the indoor lifestyle of children, plus the tendency for parents to slather on sunscreen in summer, that’s being blamed.
Painful bone ailments aren’t the only reason Britons should be taking vitamin D supplements. A daily dose could also halve the risk of serious asthma attacks, according to a review this year led by Martineau. Other diseases such as cancer, diabetes and cardiovascular illnesses have also been linked with low vitamin D levels, but trials are ongoing.
Meanwhile, research in 2015 found that taking vitamin D supplements can lower blood pressure and improve fitness, with participants able to cycle 6.5km in 20 minutes, compared with 5km when starting the experiment.
“Because low vitamin D status is associated with other risk factors for disease, such as bad diets or a high body mass index, if you dig hard enough you’ll find stuff linking vitamin D to any condition under the sun,” admits Martineau.
It’s even claimed that Mozart died of vitamin D deficiency at 35 years old in 1791 due to his vampiric penchant for composing at night.
Vitamin D Fortification
Sunshine and supplements aren’t the only source of vitamin D. A tiny amount – around 10 per cent of our supply – comes from oily fish (salmon, mackerel, herring), eggs and fortified cereals and spreads.
In Scandinavia and the US, vitamin D is added to many foods such as milk, cooking oil and butter, thereby dosing large parts of the population.
“If we are ever going to be successful in eliminating profound Vitamin D deficiency, it’ll probably be done by fortification,” says Martineau. “It will be very hard to implement the SACN recommendations because it’ll be very hard to motivate people to take supplements and remember to take them every day. There are huge barriers.”
Certain groups are more at risk of vitamin deficiency with SACN advising those with darker skin tones, from African, African-Caribbean and South Asian backgrounds to take the supplement all year round – indeed, vitamin D deficiency is estimated to affect 90 per cent of those in ethnic minority communities compared with half of white Britons.
Thanks to their northern latitude, Scots are also particularly affected by low vitamin D levels. But the SACN recommendations provoked some confusion.
As sunscreen blocks vitamin D, how are people going to make the nutrient while also protecting themselves from skin cancer? “My take is you can have the best of both worlds,” says Martineau. “Expose yourself to the sun in a sensible way, being careful not to burn, but also take a vitamin D supplement so you’re not deficient.”
While research continues to make news regularly – last month separate studies claimed low levels could cause SAD and dementia – science is only beginning to unlock the nutrient’s power.
“If we are serious about tackling this problem, the SACN recommendations are a good start but it’ll take much more than persuading the population to take daily supplements,” says Martineau. “We really shouldn’t be seeing things like rickets in the 21st century.”
For more information visit gov.uk/government/publications/sacn-vitamin-d-and-health-report
The A to K of vitamins
What do other vitamins do and what’s the best food to find them in?
Good for immune system, vision
Found in cheese, eggs, liver
Government-advised daily dose 0.6mg (women) 0.7mg (men)
Good for Breaking down and releasing energy from food
Found in Vegetables and fruit
Government-advised daily dose 0.8mg (women), 1mg (men)
Good for Protecting cells – lack of vitamin C can cause scurvy
Found in Oranges, peppers, strawberries
Government-advised daily dose 40mg a day
Good for Healthy skin and eyes
Found in Nuts and seeds, wheat germ
Government-advised daily dose 3mg (women), 4mg (men)
Good for Blood clotting, healing wounds
Found in Green leafy veg such as broccoli and spinach
Government-advised daily dose 0.001mg a day for each kilogram of your body weight