Sunday, April 06, 2008
Research
Scientists have found far lower doses of algae than of fish oils - the best known source of omega-3 - are needed for a beneficial effect.
A study carried out at King's College London found omega-3 derived from algae lowered blood pressure and could ultimately reduce the risk of heart disease.
The small study, published in the Journal of Nutrition, followed 38 men and women aged 40 to 65 for three months.
They took either a dummy pill or a purified oil rich in the omega-3 fatty acid docosahexaenoic acid (DHA).
The DHA was extracted from the marine algae crypthecodinium cohnii.
The research found a daily supplement of 0.7g of DHA lowered diastolic (resting) blood pressure by 3mm of mercury (Hg). A 3mm reduction in the average population blood pressure could help to prevent thousands of heart attacks and strokes, the researchers said.
Previous studies have shown doses higher than 2g to 3g of omega-3 derived from fish oils are needed to lower blood pressure, they added.
The study's lead author, Professor Tom Sanders, head of King's College London's Nutritional Sciences Research Division, said: "Our findings provide further evidence that relatively small amounts of this form of omega-3 help promote a healthy heart.
"There are long-term worries about the sustainability of fish stocks and our results suggest that a sustainable vegetable source synthesised by algae may be useful for preventing cardiovascular disease.
"Importantly, this form of DHA is acceptable to people who do not eat fish, for example vegetarians."
Prof Sanders said supplements for the particular type of algae were not yet available but purified oils rich in DHA are already added to some food products, such as infant milk.