The past decade has witnessed a tremendous surge in the chatter about how essential are Omega-3s for our bodies. This has resulted in a billion-dollar omega-3 supplement industry, the rise of fish oil tablets and various labelling claims on nutritional products. Having a diet with sufficient omega-3s are said to have anti-oxidant and anti-inflammatory properties and also be beneficial to our cardiovascular systems and our brains.
So what are omega-3s? is the hype real? Can we survive without eating fish or fish oil tablets? What about the vegans and the vegetarians? Can all the labelling claims be trusted?
What are Omega-3s?
In the food and nutrition context, Omega -3s are Poly Unsaturated Fatty Acids (PUFAs) and are deemed as essential fatty acids as they cannot be produced by our own bodies. Their role? unlike regular fats that are solely meant to give us energy, they form an integral part of our cell membranes throughout the body and act as a starting point for making hormones that regulate blood clotting, contraction, relaxation of artery walls, inflammation and several other functions
Playing such a prominent role has forced the scientists to study the impact/deficiency of omega-3s in the diet on our lives and in prevention of terminal illnesses.
What are the different types of Omega-3s?
The three most crucial types are
(1) ALA (alpha-linolenic acid),
(2) DHA (docosahexaenoic acid), and
(3) EPA (eicosapentaenoic acid)
ALA is mainly found in plants, while DHA and EPA occur mostly in animal foods (fatty fish) and algae. A fraction of ALA gets converted in DHA and EPA in our bodies (EPA conversion ~ 8-10%; DHA conversion ~ 0.5 – 5%). Women of reproductive age typically can convert more than twice of ALA than men and the rate is also affected by the ratio of your omega-3 to omega-6 intake. (1:3 to 1:5 is preferred)
While all 3 are essential, DHA and EPA are said to be more active forms of omega-3s as their roles in our bodies are well documented, and have been perceived to have better health benefits. Thus, apart from providing energy, ALA has only been considered as an essential fatty acid due to its ability to get converted to DHA and EPA. However, off late there has been enough research and evidence to point out that ALA itself has important functions to play in our daily wellbeing and also in possibly preventing serious diseases; like its counterparts.
Roles and Benefits of ALA
ALA does not have similar benefits as EPA or DHA, but is vital for a normal healthy life. ALA consumption has strongly been linked to having neuroprotective, anti-inflammatory and anti-depressant properties by studies. Diets with high omega-6 to omega-3 ratio (greater than 10:1) increase the risk of cardio vascular disease, strokes and coronary heart disease. ALA consumption plays an important role to maintain this balance and not having to depend on EPA/DHA supplements that have been proven to have adverse side effects if taken in larger quantities than required.
As of today, the rate of conversion of ALA to EPA and DHA can only be calculated from blood level measurements. Research is ongoing to get a more accurate measurement of this conversion through cell, animal and human studies. A few recent studies do indicate that consuming higher ALAs may result in maintaining EPA/DHA levels in our tissues and brain, but more research is underway to completely comprehend this entire process.
Roles and Benefits of EPA & DHA
EPA is utilized by our body to produce signaling molecules called eicosanoids that helps in preventing blood clots, reduction of triglyceride levels in the blood that ultimately has effects that reduce pain and inflammation.
DHA is predominantly found in the brain cells and retina. It is vital for brain development and function and is thus recommended primarily for women in pregnancy and babies during lactation and their early childhood. DHA’s presence in the brain led to a lot of research involving the impact of its incorporation in our diets on our daily lives and severe diseases or terminal illnesses.
It is mostly the combined effect of EPA + DHA that has often been studied as both always occur together in all the dietary sources. EPA and DHA reduce triglyceride levels and improve the cholesterol profile. There have been several studies indicating the anti-inflammatory properties, and improved cholesterol profile of EPA + DHA may reduce risk of chronic deceases that are common due to ageing like – heart diseases, arthritis, cancers etc. DHA has also been linked with prevention / delay in the onset of Alzheimer’s, and that it may also improve ADHD.
Dietary Sources of Omega-3s
You can derive ALA from primarily from plants. ALA is found in flax seeds, hemp seeds, rapeseeds (canola oil), walnuts.
For directly obtaining EPA and DHA (apart from the ALA conversion), we have to depend on marine sources. Fatty fish, salmon, shrimps, oysters are all excellent sources of EPA and DHA. However, it is not them that synthesize these omega-3s in their bodies; they obtain them directly by consuming seaweed and marine algae. Thus making seaweed and marine algae the only vegan/vegetarian sources of EPA and DHA.
Omega-3 supplements made from fish oils, algal oils etc. have now become a billion-dollar industry, but they must be consumed only under medical supervision if prescribed by doctors due to possible adverse side effects. It is always best to obtain your nutrition from whole food diets.
If you are a vegan or a vegetarian, make sure you have ample ALA sources in your diets as you might have to rely on the ALA conversion to EPA and DHA to satisfy the requirements. Consuming algal oil or algal oil supplements is also a safe way to ensure appropriate intake of EPA and DHA (do consult your doctor!)
A non-vegetarian must also ensure ample intake of ALA due to ALA’s intrinsic benefits and also to maintain a healthy ratio of omega-3 to omega-6 in your diet. EPA and DHA can be easily obtained through consumption of sea-food or fish oil supplements.
However, if you are a conscious consumer that cares about the impact of our diets on our environment, please do check out the blog – and the blog –
Our reliance on seafood as a source of omega-3 has a huge impact on our environments either if consumer directly or as supplements.