Omega-3 fatty acids for heart and overall health
Dietary fat is a macronutrient essential for good health. Fat provides insulation that helps maintain body temperature, serves as a source of stored energy, and is crucial in the absorption of a number of vitamins. However, certain types of dietary fat, when consumed in excess, can have negative effects on our health. Saturated fats, found in red meat and dairy (butter, cheese, ice cream), and trans fats obtained by the industrial processing of oils (shortening, margarine, industrial frosting) raise cholesterol levels and thus increase the risk of atherosclerosis - hardening and narrowing of the arteries that can lead to heart attack or stroke. On the other hand, mono- and polyunsaturated fats found in avocado, nuts, olive oil, and oily fish have beneficial effects on heart health and are widely regarded as a healthy alternative to the saturated and trans fats. American Heart Association recommends that healthy
people consume less than 7% (or 16 grams for a 2000 calorie diet) of their daily calorie intake as saturated fat. The rest of the fat intake (13-28% of calories or ~ 29 -62 grams) should be in the form of mono and polyunsaturated fat.
One of the first indications that some fats might be healthier than others came from the studies on Inuit nutrition. Despite consuming a large portion of calories as fat, the Inuit population had lower levels of cholesterol and triglycerides in the blood (dietary fat is composed of triglycerides) than their counterparts consuming traditional Western diet. Such favorable lipid profile was thought to be the reason why the Inuit rarely developed diabetes and cardiovascular disease.
It is now well established that fatty acids from fish (the primary food of the Inuit) - specifically the long-chain omega-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – do, indeed, lower the level of triglycerides in the blood and are considered to be heart healthy.
Omega-3/Omega-6 PUFAs balance
Unfortunately, a typical Western diet is deficient in omega-3 PUFAs. Industrialization and modern agricultural methods focused on the inexpensive mass production of food items have greatly contributed to the decline of omega-3 PUFAs and the simultaneous rise of their close relatives, omega-6 PUFAs. Both types of PUFAs are structural components of cell membranes and have important albeit opposing physiological functions. While omega-3 PUFAs reduce inflammation and lower the chance of blood clot formation, omega-6 PUFAs promote both processes. The nutritional imbalance between these two types of PUFAs tilts the equilibrium in the body to the side of inflammation and the prothrombotic state, which contribute not only to the cardiovascular diseases but also to many chronic diseases, such as diabetes and cancer. Overconsumption of omega-6 and deficiency of omega-3 PUFAs is believed to be responsible for what is known as “the Israeli paradox”. This paradox refers to the observation that, despite low consumption of saturated fats and high consumption of unsaturated fat, Israelis had the same rate of heart disease, cancer, and diabetes as their Western counterparts with unhealthy fat consumption. Unusually high consumption of omega-6 PUFAs, in particular, linoleic acid (8% higher than in the U.S. and 10-12% higher than in most European countries), was postulated as one of the major contributors to the high prevalence of the metabolic syndrome in Israel.
Balancing the intake of omega-3 and omega-6 has shown promise in the treatment of rheumatoid arthritis, asthma, and depression. However, the exact ratio of omega-3 and omega-6 that is needed to correct a certain disorder is far from known.
Still, steps can and should be taken to balance the consumption of these two important PUFAs:
Consume oily fish 2-3 times a week. Oily fish are the best source of EPA and DHA omega-3 PUFAs. The highest levels are found in mackerel, salmon, herring, tuna, trout, sardines and anchovies.
Consume flax and chia seeds daily. They are the richest sources of an essential omega-3 PUFA, alpha-linolenic acid, ALA. ALA can be converted into EPA and DHA in our bodies although the conversion efficiency varies greatly between people (for example, the conversion is more efficient in women than in men) and depends on the presence of other nutritional factors such as vitamins and minerals.
Opt for meat, dairy, and eggs from grass-fed animals. The level of omega-3 PUFAs in these products depends greatly on the animal diet. Because grass is naturally abundant in omega-3 (unlike corn that is rich in omega-6), grass fed beef has twice as much omega-3 PUFAs than the grain fed beef.
Diversify your diet. A monotonous diet that relies heavily on cereal grains (rice, wheat, corn) not only creates an imbalance in PUFAs but can bring about other nutritional deficiencies as well. Enrich your diet with vegetables and fruits that, although not particularly high in omega-3 PUFAs, are rich in vitamins, minerals, and antioxidants and thus affect the metabolism of fatty acids (for example, vitamins B3, B6 and C and minerals zinc and magnesium are cofactors necessary for proper functioning of enzymes that convert ALA to EPA and DHA).
Avoid omega-6 loaded vegetable oils. Instead of sunflower, cottonseed, soybean, sesame and corn oil use olive oil that has a considerably lower amount of omega-6 PUFAs.
Take a fish oil supplement. If you are not consuming sufficient amounts of oily fish or have high blood triglycerides and a history of coronary heart disease, fish oil, rich in EPA and DHA omega-3 PUFAs, will be an excellent addition to your diet. In clinical trials, fish oil supplementation has been proven effective in lowering blood triglycerides and has shown promise in the prevention of cardiovascular events (stroke, heart attack…) in patients with a history of coronary heart disease.
How to use fish oil
The dose of fish oil you will need will depend on your health and diet.
Healthy people who consume oily fish several times
a week do not need any supplementation with fish oil. One gram of EPA and DHA daily is considered a preventive dose in people with a previous history of coronary heart disease. Higher doses, from 2-4 g a day, are needed to lower triglycerides. Because omega-3 PUFAs can affect blood-clotting, doses higher than 3g a day should be taken with doctor’s supervision.
Fish oil supplements contain varying amounts of EPA and DHA. Read the label carefully to find out how much EPA and DHA is contained per fish oil soft gel.
If you eat oily fish (the best food source of EPA and DHA) twice a week as recommended, you are getting about 500 mg EPA and DHA daily (there is more than 1.5 g of omega-3 fatty acids per 3 oz. serving of salmon). Adjust the dose of the supplements you take according to how much EPA and DHA you are already getting in your diet.
Absorption of fish oil is most efficient in the presence of dietary fat. To optimize the absorption, take fish oil supplements with a meal that contains some healthy fats.
Fish oil supplements are found to be generally safe when used at recommended doses.
Omega-3 fatty acids are known to affect blood-clotting. Consultation with your doctor is needed for high dose therapies (over 3 grams daily).
Studies have shown that fish oil, specifically DHA, can increase the level of LDL or “bad cholesterol”. Because saturated fats also contribute to increased LDL levels, it is important to control the amount of saturated fats in your diet while taking fish oil supplements. If you have a history of coronary heart disease, saturated fats should comprise only 5-6% of your daily calorie intake, which for a 2000-calorie diet translates to about 13 grams a day. Western diet, typically high in red and processed meat as well as dairy, overreaches this limit rather quickly. Focus on eating whole foods - vegetables, fruits, nuts, fish, lean meat - and you will not have to worry about counting grams of saturated fat in your diet.
Another way to lower the risk of LDL increase is to use fish oil supplements that contain mainly EPA. Studies have shown that DHA - not EPA - is responsible for LDL increase.
Fishy aftertaste and smell, as well as gastrointestinal disturbances, are sometimes reported with fish oil use. Enteric-coated supplements usually minimize these side effects.
Although concerns were raised about the effect of omega-3 fatty acids on blood glucose levels, especially in diabetic patients, studies have shown no adverse effects.
People allergic to fish and fish products should not use fish oil supplements.
Fish oil supplements
There is a variety of high-quality fish oil products in the market. The one you choose will depend on your particular needs.
Regular strength soft gels. Nature Made offers several products that are USP (Unites States Pharmacopeia) certified:
1000 mg with 300 mg omega-3
Highly concentrated omega-3 PUFAs. If you need higher doses of omega-3 fatty acids, you can opt for more concentrated supplements that are IFOS (The International Fish Oil Standards Program) certified:
Nordic Naturals Ultimate with 1000 mg omega-3
Carlson Maximum with 2 000 mg omega-3
Enteric-coated soft gels. If you experience fishy aftertaste and burps, use enteric-coated soft gels that minimize those side effects (also IFOS certified):
OmegaVia with 1 105 mg omega-3
EPA only supplements. If high LDL levels are a concern, choose a product that predominantly contains EPA (IFOS certified):
OmegaVia EPA 500
Prescription formulations. For people with really high triglycerides levels, omega-3 PUFAs are available by prescription as well. There are currently five different formulations that vary in dose and EPA-DHA ratio. Talk to your doctor to decide which is the right choice for you.
Last updated: March 24, 2017