Scottish vitamin D study ‘irresponsible’

A study conducted by ScotCen Social Research and commissioned by the Food Standards Agency and Scottish Government has stated that the average level of vitamin D in the Scottish population is above the current indicator of optimal vitamin D status, even though it also found that over a third of participants recorded sub-optimal levels of vitamin D.

Published under the heading ‘Average level of vitamin D is adequate in adults living in Scotland’, on FSA Scotland’s website, the study has been questioned on two levels. Firstly for indicating the results showed the Scottish population had an ‘adequate’  level of vitamin D when 33% were actually found to be lacking; and secondly for using the standard of 25nmol/l as being an optimal level for the vitamin.

The survey, using data from participants in the 2010 and 2011 Scottish Health Surveys, analyzed over 1,400 blood plasma samples for 25hydroxy(OH) vitamin D, the circulating metabolite of vitamin D. In both males and females and across age groups, an average of 37.5nmol/l was recorded, with the optimal level being set at 25nmol/l or over.

Charles Milne, the director of the FSA in Scotland, commented: “This research provides us with a comprehensive look at the vitamin D status of adults living in Scotland. This further strengthens the evidence base and will be carefully considered as part of the ongoing SACN vitamin D review.”

However, the study has reinforced some concerns about the current levels used to determine vitamin D deficiency.

Marcus Webb, technical director of Hadley Wood Healthcare, commented: “I think it’s down to where you set your cut-off as to what you consider deficient – the researchers set theirs at 25nmol/l for vitamin D. Anybody who’s just above 25nmol/l has no way got a good level of vitamin D. They are literally just above being deficient.”

Andrew Thomas, founder and MD of BetterYou, agrees: “The conclusion of the authors that the average serum level of 37.5nmol/l is ‘optimal’ is not only mistaken but irresponsible … Even the conservative estimate of the Department of Health suggests that a level below 50nmol/ would be classed as insufficient, and most advise a ‘target’ serum level of 75nmol/l as optimal.”

“I would say that this shows that the population is at the low end of adequate, verging on deficient, and very few are optimal. There’s no question that vitamin D is a massive public health issue which is cheap as chips to correct – vitamin D supplements are cheap and safe,” adds Webb.