Bill Harvey: Omega-3's effect on eye health
Author: Bill Harvey
The problem of whether to trust scientific research is a common theme in this comment column. And I do not see an easy option other than to always question the validity of findings. This even applied when research is from a respected source and published in peer-reviewed journals.
A good example of this the well-respected and often-cited AREDS2 study. Many people gleaned from this that omega-3 had no benefit in reducing the risk of progression of age-related macular degeneration.
It was only after discussion of the paper that many authorities noted that the patients under study were sampled from the affluent North American population and were likely to already have levels of omega-3 in their existing diet that might have masked any impact of supplementation when compared to controls from the same group.
A more recent example of a study to be questioned is the recently published DREAM study. This suggested there is little effect of omega-3 upon the ocular surface and therefore use of it in supplements to help those with dry eye disease might be questioned. Many authorities, however, have questioned the use of olive oil as a placebo.
Olive oil contains very few omega-3 EFAs (around 1%), which is probably why it was chosen as a placebo. However, it can contain up to 20% of omega-6 essential fatty acids and modern supplements are not simply omega-3 supply. Look out for a reasoned discussion of this next week.
Talking of scientific interpretation, conscious of my forthcoming visit to the European Academy conference in Croatia (look out for reports), I went shopping for sunglasses yesterday in the sunshine. Being easily bored, I instead had a drink al fresco and couldn’t help but notice the good citizens of Bristol were not all suitably protected from the new sunny world we are entering. I reckon over the space of one hour, around 40% wore sun specs. Try this yourself – it’s shocking.