The public should be boosting their vitamin D intake with supplements because of a lack of bright sunshine in the UK, government health experts have suggested.
The bleak British weather is stopping much of the population from receiving healthy amounts of the essential vitamin from sunlight and natural food sources alone are not enough to boost levels, they added.
The Government's independent Scientific Advisory Body on Nutrition (SACN) made the recommendation after studying the links between vitamin D levels and a range of health problems, including musculoskeletal health, heart disease, type 1 diabetes, cancer and multiple sclerosis.
Current government advice is that at-risk groups, including pregnant women, children up to the age of five, adults over 65, and people with darker skin as well those who do not expose their skin to sunlight, should take a daily vitamin D supplement.
However, if SACN's draft recommendations are adopted it could lead to new guidance affecting the whole population.
Dr Adrian Martineau, an expert on vitamin D's effect on health at Barts and the London School of Medicine and Dentistry, said the new advice marked a "sea change" in thinking.
He told the Independent on Sunday: "Before this, the general assumption was that adults were able to make all the vitamin D they needed from sunshine, and didn't need to have any dietary or supplementary intake.
"The action of sunlight on the skin in the UK is highly variable for different populations depending on the time of year and the latitude – you'll get more UVB in Brighton than in John O'Groats – and finally, how much skin is exposed and the colour of skin.
"SACN was right to say that we can't rely on sunshine in the UK to meet the vitamin D requirements. That's a major and important change. It's a big step forward that this is now officially recognised."
Recent data published by Public Health England highlighted that more than one in five people have low levels of vitamin D, which is essential for keeping teeth and bones healthy.
SEE ALSO:
5 Signs You Need More Vitamin D In Your Life
Sunny Days And Blue Skies May Not Make Us Happier, Suggests New Wellbeing Study
A lack of the essential nutrient can cause rickets in children and in adults can lead to osteomalacia, causing the person's bones to become weak and painful, and hampering mobility. The best source of vitamin D is sunlight, and it only occurs naturally in a few foods, such as oily fish and eggs.
The Draft Vitamin D and Health report said: "It is proposed that the recommended nutrient intake is applicable throughout the year, as a precautionary measure, to cover population groups in the UK identified to be at risk of minimal sunshine exposure as well as unidentified individuals in the population with minimal sunshine exposure who would be at risk in summer.
"Since it is difficult to achieve (safe intake) from natural food sources alone, it is recommended that consideration is given to strategies for the UK population to achieve the recommended nutrient intake."
Professor Hilary Powers, chair of the SACN Vitamin D working group, said: "It is important to remember that this vitamin D report is a draft so the recommendations may change after the consultation period.
"SACN will be publishing their final recommendations in early 2016 and until then the Government's current advice on vitamin D remains in place."