Teenage girls and young women who are overweight have a higher chance of being deficient in vitamin D, scientists have found in research that strengthens the case for wider use of supplements.
The research shows that even in a sunshine-rich climate similar to Sydney's it is possible for young people to lack the essential vitamin, which the body usually produces from sun exposure.
Using scans to measure the women's body fat - not just their weight - the scientists, from the University of Southern California in Los Angeles, found a strong link between excessive body fat and low vitamin D levels.
It was possible low vitamin D could cause weight gain, lead researcher Richard Kremer wrote in the Journal Of Clinical Endocrinology And Metabolism. It was also possible that "body fat may contribute to low … levels by trapping vitamin D in fat tissues".
Low vitamin D has been linked to serious health problems, including cancer, diabetes and the bone disorder osteoporosis. But the Californian study found bone growth was the same whether the women (all of whom were white and aged 16 to 22) were vitamin D-deficient or not.
Louise Baur, a pediatrician at the Children's Hospital, Westmead, said some Australians were more at risk of vitamin D deficiency, particularly people with darker skin or who wore a lot of clothing. She said evidence linking body fat and vitamin D depletion was becoming stronger but warned: "There's nothing to say that vitamin D supplementation will decrease your body fatness."
Rebecca Mason, a professor of endocrine physiology at Sydney University's Bosch Institute, said in prehistoric times vitamin D stored in summer - when people carried more body fat - might have been released into the blood during winter - when the body used fat stores. But today, people who put on weight rarely lost it again, meaning vitamin D might never be released.
Professor Mason said many people had low vitamin D levels and it was reasonable for concerned individuals to take vitamin D pills.
Yes, because you will process D differently when you're at your ideal weight. There are a lot of reasons to lose weight. I'm losing and I'm really anxious to see if I can taper off of some of the RA drugs. Maybe how we absorb drugs are different when we're heavy. Maybe I can decrease MXT and take Humira every 2 weeks instead of weekly. That's my goal that I've been working towards. Lindy
You go, Lindy!
Pip, have you had D levels checked and if so are they normal? I have my own little research study going. Losing weight so I might possibly use less RA meds. My body may absorb and not require as many drugs if I'm at my ideal weight. From the research I've done there's a great possibility that this could happen. We'll see. Lindy
Yes, Lindy, from what I've seen, your study of one is right on target. Yeah, I'm low but also confused. IM doc said he never took the 4 blood tests. I know he did because I had to go back and pick up the 4th one via an OK. He looked in chart and said, no, only took 1 D test. Came back to Cali and LOOKED for the report he sent and...can't find it. So, know I'm low, at least 2X by this same doc, and AP doc mentions it occassionally, but...since I'm on the D fence I just ignore.