Vitamin D helps people absorb calcium, making it essential to strong bones and healthy teeth. But with nearly one in 5 people in the United Kingdom (UK) lacking sufficient vitamin D levels, the Science Advisory Committee on Nutrition (SACN) in the UK is now recommending that people triple their daily intake.
“Until now it has been assumed that sunlight would provide the vitamin D needed by most of the population all the year around,” said Professor Hilary Powers of the Department of Oncology and Metabolism at the University of Sheffield and chair of the SACN’s review.
The body makes most of its vitamin D from direct sunlight on the skin, though people get small amounts from oily fish and fortified foods like cereals and fat spreads. According to the review, people older than age one need 10 micrograms of vitamin D each day. The average intake from food and supplements is only about 3 micrograms.
Groups most at risk of vitamin D deficiency include:
- Those who don’t spend much time outdoors, such as the elderly;
- Ethnic minority groups with darker skin, which doesn’t make vitamin D as easily;
- Those who cover their skin for religious and cultural reasons;
- People in occupations with limited sunlight exposure such as nightshift workers.
“There are very few foods that contain a good source of vitamin D, so it is very important to ensure we include a variety of oily fish such as tuna, salmon, and sardines; eggs; and certain fortified breakfast cereals in our diets,” said Powers.
A lack of vitamin D can lead to serious conditions such as rickets in children and osteomalacia in adults, which can cause bones to soften, weaken, and become deformed in some cases. Other diseases such as diabetes and cancer have been linked to low vitamin D, though the evidence is still not strong.
“In the 1950s after World War II, the government issued a dose of cod liver oil to children every day to supplement their diets with a good source of vitamin D, but it was later thought to be unnecessary,” Powers said. “The government now needs to look at the evidence and recommendations in the report and consider a strategy to help people in the UK increase their vitamin D intake.”