Two population studies in the Unites States observed a higher risk of macular degeneration among people who consumed greater quantities of vegetable fats [2,3]- margarine being on obvious contributor. It has been suggested that higher levels of trans fats may be responsible for this effect, though another population study in the U.S. found no link between vegetable fat and macular degeneration - it actually showed a higher risk among those who ate butter. [4]
As I mentioned previously, the levels of trans fats in American cooking oils and margarine is much higher than that found in Australian products. In fact, two Australian studies found no relationship between the intake of vegetable oils and macular degeneration [5,6] - the latter actually finding a greater risk among people with higher intakes of animal fats. Read More....
The bottom line is that Australian margarine's certainly do not increase the risk of macular degeneration or any other kind of blindness. Australian current affairs program 'Today Tonight' certainly didn't let the truth get in the way of a good story back in July 2004, when they reported a segment on how vegetable oils supposedly increases the risk of macular degeneration.
Today Tonight only mentioned the studies in the U.S. which showed the link, but did not mention those which found either no association or a protective effect. Moreover, they did not mention the significant difference between trans fat levels in Australian foods compared to American foods.
They interviewed Dr Paul Beaumont from the Macular Degeneration Foundation as their only source of supporting information. When I called the Macular Degeneration Foundation however they told me that despite the media attention, they had no official position on vegetable oils, that the evidence was mixed and that more research was needed to make any kind of link between dietary fat and macular degeneration. The Macular Degeneration Foundations web site makes the following statement:
American studies have shown that patients eating a lot of vegetable oil, margarine, processed and baked foods containing more oil developed MD and lost vision more rapidly. There is disagreement as to whether this relates to the Australian public. At present, cold pressed olive oil appears to be the safest. Further research is needed to determine what effect oils have on eye health. Contact your attending doctor for further advice.
The Today Tonight story was deliberately exaggerated to create the fear that 'vegetable oil is everywhere' and is 'sending us all blind'. Although these were not the precise words Today Tonight used, this is essentially the message that many viewers received, and is one of the most common concerns people convey to me.
As a general rule of thumb, any kind of health related information you see on shows such as Today Tonight or A Current Affair should be taken with a grain of salt, to say the least. Any kind of health related information (or any information at all for that matter) you recieve through email fowards should be completely disregarded (or see snopes.com to check its validity)
