Omega-3 fatty acids; rings a bell? Chances are that you have heard of their health benefits. For instance, they help lower bad cholesterol and are good for the heart. But did you know that they offer a range of other benefits ranging from cancer prevention to mood elevation? Are you also aware that these benefits are related to the type of omega-3 you consume?
Benefits
Omega-3s belong to the class of essential fatty acids. That means the body cannot synthesise them from scratch and has to get them from food. Since essential fatty acids and more specifically omega-3s are a part of cell membranes through the body, the health benefits accruing from consuming adequate amounts are many.
One of the most well known is the effect on LDL or ‘bad fat'. As omega-3s help reduce LDL levels the benefits for heart health are obvious. Additionally as components of cell membranes, these are necessary for the proper functioning of the brain and the nervous system. Other health benefits include helping prevent heart disease and stroke, controlling arthritis and boosting immunity.
The strong scientific evidence for this led the American Heart Association to recommend omega-3 supplements as the first nutritional supplement.
Two of the most important essential fatty acids are ALA (Alpha Linolenic Acid) and LA (Linoleic Acid). ALA is converted to long chain omega-3 fatty acids inside the body while LA is converted to long chain omega-6 fatty acids. These promote clumping of platelets, clotting of blood within the vessels and control inflammatory reactions.
Apart from ALA, there are other ‘omega-3' fatty acids: DHA (Docosahexaenoic Acid) and EPA (Eicosapentaenoic Acid) but these are not essential fatty acids, as the body can synthesise them from ALA.
This brings us to the question: which type of omega-3 offers maximum benefits? As the precursor to both DHA and EPA, ALA wins. ALA-based omega-3 fatty acids offer benefits of all omega-3s.
ALA and its omega-3 derivatives together with LA and its omega-6 derivatives are very important for the body and confer significant health benefits. However their ideal ratio (LA:ALA = 2:1) has to be maintained. Unfortunately modern lifestyle and faulty diet have ensured that the ratio is highly skewed.
It is important to restore this ratio because, although LA and ALA are both essential, they tend to compete for enzymes. Any imbalance in the ratio or any increase in one family of fatty acids may jeopardise the metabolism of the other, affecting its incorporation into cell membranes. Since the amount of LA in our diets is far more than it should be and since the amount of ALA is not sufficient, it is important to supplement our diets with ALA-based omega-3s.
Food source
The best food source of ALA is walnut. EPA and DHA are found in fish but not ALA. As far as omega-3 EPA and DHA is concerned, eating fish is a good idea. But this does not take vegetarians into account. Also the dangerously high level of mercury in most fish means that the risks outweigh the omega-3 benefits on offer. Fish does not provide ALA.
Other sources of omega-3 which include soya bean in the form of tofu, kidney beans (rajma) as well extra virgin olive oil (on salads as a dressing).
To sum up, ALA-based omega-3 consumption offers significant health benefits and is a prudent health choice. In making the right health choices, it is always useful to remember that eating healthy depends so much more on what you eat than on how much you eat.
The writer is a Delhi-based dietician.
