A DNA community member asked about benefits and risk of incorporating Omega -3 fats in his meals. This is first of a series of blogs on Fat – the “good and the “bad” kind and its critical role in our food and meal matrix to support good health for South Asians.
Adding Omega 3 to your meals is an excellent decision.
What is Omega -3?
Omega 3 fatty acids are present in all cell membranes and are essential ingredients for the body to manufacture a range of hormones required to manage inflammation, arterial health, blood clotting – all of which play critical role in controlling and managing chronic diseases prevalent among Indians and South Asians. These are essential fatty acids because your body cannot make them and the only way to get them is to consume them.
Multiple independent sources provide strong evidence that Omega -3 (n-3) Poly Unsaturated Fatty Acids (PUFA) reduce risk of cardiac death. National and international guidelines have converged on consistent recommendations for the general population to consume at least 250 mg/day of Omega -3 or at least 2 servings/week of oily fish
There is increasing, but not definitive evidence, of Omega-3 being helpful in treating a range of non-cardiac health conditions like rheumatoid arthritis , Crohn’s disease, lupus, eczema, and may play protective roles in cancer and other conditions.
Omega-3 fatty acids are shown to be more effective than placebo for depression in both adults and children in small controlled studies and in an open study of bipolar depression. I will detail the benefits and (very few) risks of Omega -3 identified in health and nutrition studies in a separate blog.
But For Now Let Us Talk FOOD…
Foods high in Omega-3 include animals in the marine food chain, primarily fish, and non-animal food sources like nuts and seeds like chia, flax and walnuts. However the kind of Omega 3 in fish (animal sources) are different from the Omega 3 from plant sources.
There are three main kinds of Omega 3 fatty acids:
- EPA and DHA kind are animal-based and are proven to have the beneficial health effects.
- ALA kind is primarily plant based and has not been shown to have the same health benefits as DHA or EPA. Our bodies can convert ALA from plant sources into EPA and subsequently DHA, in very small amounts and only under right conditions. ALA is used by the body primarily as fuel. They are not harmful and should not be avoided. World Health Organization recommends a daily ALA intake of 0.8-1.1 grams.
How Much Omega 3 Should I Eat?
- Children need approx. 50 mg of Omega 3 per day until, they are teenagers. Typically two eggs per day or one egg per day and 50 g of fish few times a week will suffice.
- Teenage boys need ~ 100 mg per day while girls need ~75 mg per day to maintain good health. Typically two eggs per day and 100 g of fish few times a week will suffice.
- For primary prevention healthy South Asian men and women with no cardiovascular risk or elevated triglyceride should consume ~500mg of Omega 3 to support future disease prevention.
- South Asian men and women Adults with proven cardiac risk or high triglycerides need to consume at least 1000 mg per day for secondary preventive benefits.
Do All Fish Include Omega 3? Which Fishes Are Good For Me?
All fishes are not created equal. It is a fatty fish that is loaded with Omega-3 fatty acids.
The rising popularity of Basa, primarily sourced from Vietnam, is replacing the stock fish – river sole in North India, bhetki in East India and ghol or pomfret in West India – in restaurants across India. 150 g of Basa provides approx. 700 mg of Omega 3. If you consume Basa 2-3 times a week, you are providing your body with the minimum amount of Omega 3 required for an adult. However, it does not provide adequate Omega 3 to support primary prevention of cardiovascular disease and lipid disorders like high triglycerides.
I remember eating Rohu or Katla growing up in India. These fishes are much richer in Omega 3 and 150 g of each of them are packed with 1100 mg of Omega 3, which eaten 3-4 times per week provides adequate Omega 3 to support primary disease prevention.
Tilapia is commonly served in restaurants in the US and 150 g filet provides only 320 mg of Omega 3 which falls far below the 500 mg per day needed for primary disease prevention. South Asians in the US have access to a wide range of fatty fish rich in Omega 3 – Catfish, Halibut, Salmon, Striped Sea Bass, and Albacore Tuna are particularly recommended.
I would consider two other factors in selecting my fish based meals.
- The ratio of Omega 3 to Omega 6 in the fish, and
- Risk of contaminants like mercury, PCB etc.
Fishes Have Different Ratio of Omega 6 vs. Omega 3 Essential Fatty Acids
Omega-6s and Omega-3s don’t have the same effects. A lower ratio ( less than 3:1) of Omega-6/Omega-3 fatty acids is more desirable in reducing the risk of many of the chronic diseases of prevalent in Indians and South Asians .
The largest source of Omega 6 in our diet are from vegetable oils. Oils like Sunflower, Corn, Soya have very high Omega-6/Omega-3 ratio. Olive oil has better balance of Omega-6/ Omega-3 and we should prefer over Sunflower and Corn in our general daily consumption. Sunflower, Corn, and Soya oil should be avoided while cooking fishes low in Omega 3 like like Basa and Talipia.
Total intake of Omega 6 /Omega 3 ratio higher than 10:1 has been proven to be harmful in adults. Fishes high in Omega-3 like Wild Salmon, Mackerel, Rohu are more desirable over Basa or Talipia.
Mercury is the primary metal that leads the way in contamination of fish followed by PCB5, chlordane, dioxin, and DOT. The important factor in fish contamination is not only what fish consume, but also and essentially the feeding location of the fish. All things being the same, the higher the fish is on the food chain, higher the chance of chemical contamination in the fishes’ body.
Make sure you are consuming adequate animal based Omega-3 in your diet as they are essential Fatty acids and your body cannot produce them, but needs them.
Indians and South Asians should consume at least 30 – 40 g per week of Omega-3 for primary disease prevention.
If you have a proven cardiac or lipid disorder, you should consume 70g per week and focus on low contamination fatty fishes with good Omega 3 to Omega 6 ratio like wild salmon and mackerel.
Fishes are the Best source of Omega-3.
Plant Omega-3 are good source of energy and small amounts convert into the helpful Omega-3 and provide necessary nutrients.
Egg yolk is a good source of animal Omega-3.
Understand where your fish in coming from, but do not let the fear of contamination distract you from the good health and disease prevention value of clean fish.
Stay Informed. Stay Healthy!