July 13th, 2006
There are numerous studies that have shown that the long-chain polyunsaturated fatty acids, LC-PUFAs, have good health effects. The two most important omega-3 fatty acids DHA and EPA, found in fish oil, may also protect the eyes from age-related macular degeneration (AMD) - this according to two new studies published in the journal Archives of Ophthalmology. AMD is an age-related disease that can lead to vision loss among elderly people.
Study from the USA (Seddon, 2006)
Seddon et al. studied 681 elderly male twins. Data was collected through questionnaires and the participants answered questions about smoking, physical activity and eating habits. One third of the participants (222 men) was diagnosed with intermediate to late-stage AMD, whereas the remaining 459 men had early or no symtoms of the disease.
The men who ate fish at least twice a week were 45 % less likely to have this eye disease, compared to those who ate fish less than one a week. Also omega-3 supplements had a protective effect. The researchers furthermore note that the risk of developing AMD was lowest among those who ate a high amount of omega-3 and limited amounts of omega-6, i.e. that the omega-3/omega-6 ratio was high. The ratio should be at 1:3-1:4 say the researchers.
Smoking nearly doubled the risk of developing AMD. Smokers had a 1.9-fold increased risk and past smokers a 1.7-fold increased risk of developing AMD, compared to none-smokers.
Study from Australia (Chua, 2006)
In the australian study 2900 people participated and the average age was about 65. Participants answered questions about their eating habits and five years later their eyes were examed for AMD.
Individuals who consumed fish at least once per week were 40 % less likely to develop early-stage AMD compared to those who never or rarely ate fish (less than once a month). Late-stage AMD was also less frequent among fish eaters.
In these two studies it was not specified what type of fish that was eaten. Oily fish such as mackerel and salmon are rich in omega-3 fatty acids, but farmed fish does not always contain omega-3s. Read more about omega-3 in food.
Seddon, J. Archives of Ophthalmology, juli 2006; Vol. 124: pp.
Chua, B. Archives of Ophthalmology, juli 2006; Vol. 124: pp. 981-986.