Adolescents aged from 14 to 18 have dangerously low levels of vitamin D—described as the ‘sunshine vitamin’—at a time when their bone mass is still developing, say researchers from the University of Surrey.
The levels of the vitamin were checked at the end of the summer when they should have been at their highest following a summer in the sun, the researchers discovered when they analysed blood samples from 110 teenagers.
Adolescents are more likely to want to stay indoors anyway, say the researchers, but years of ‘safe sun’ advice can’t have helped, especially as it’s based on exposure to the heat and sun of Australia, which is far more intense than that experienced in Northern climates.
At the very least, say researchers, adolescents should be supplementing with D3 vitamins, especially during the winter when the sun is too weak to naturally replenish the body’s vitamin D levels.
During the study, half the adolescents were given varying doses of vitamin D supplements and the rest had a placebo, or dummy supplement, for 20 weeks during the winter.
The researchers recommend that adolescents supplement with between 10 and 30 ug vitamin D3 every day, especially in the winter.