Omega-3s - MEG-3
Omega-3: Every Body Needs It!
Omega-3s are considered a healthy fat that is critical to our brain and heart function, as well as our overall well-being. Our bodies cannot produce Omega-3s on their own at significant levels, so as a result, it is essential that we consume this type of fat in our daily diet. More than 30,000 scientific studies over the past 35 years show the benefits of Omega-3 at every life stage – from before birth and into your senior years, Omega-3s are one of the most-studied nutrients of all time.
Omega-3s are found mainly in marine fish such as tuna, salmon, sardines and anchovy, as well as algae and a few plants. Fish is the primary source of both Omega-3 EPA and DHA – the dynamic duo of fatty acid nutrients that positively support your health.
Not a fish fan? That’s OK, because there are high quality choices for you with purified, concentrated Omega-3 EPA and DHA fish oil supplements and enriched foods to make sure you’re getting your daily dose.
The Omegas (3, 6 & 9)
Fatty acids are categorized based on their chemical makeup. The Omega-3, Omega-6, Omega-9 classification of fatty acids is based on the position of certain carbon-double bonds inside the fatty acid molecule. Omega-3 and Omega-6 are often considered “essential fatty acids” because although we need them to be healthy, our body does not readily produce them at significant levels. It’s essential that we get them through our daily diet.
Omega-6 fats compete with Omega-3 fats in the body for the same enzymes and pathways in the body. The fat consumed in abundance will dominate the reactive state in the body. Vegetarians and children, who avoid fish for different reasons, are particularly at risk of having low Omega-3 levels, and overabundance of Omega-6 intake.
Long Chain vs. Short Chain
Omega-3 fatty acids are further classified into two groups – longer chain and more unsaturated such as EPA and DHA, and “shorter chain” such as ALA. The longer chain, highly unsaturated fatty acids – EPA and DHA – are the ones that our bodies benefit from the most. These long chain fatty acids are readily available from oils naturally found in cold water fish such as salmon, tuna, sardines and anchovy. The shorter chain ALA is found in plant sources such as flax and chia seeds. The human body can convert ALA into the more useful EPA and DHA, but only at a very low efficiency.
Not all Omega-3s are the Same
In comparing sources of Omega-3s, it is important to understand that this class of essential fatty acid comes in different forms. Marine sources such as fish provide Omega-3 as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), while plant sources such as flax provide Omega-3 as alpha-linolenic acid (ALA). The health benefits attributed to Omega-3 are based on the functions of EPA, DHA and ALA in the body – and they all provide different health functions.
EPA and DHA
The Omega-3s EPA and DHA are the “dynamic duo” of the healthy fat world. EPA and DHA work as a team to maintain good health at all stages of life by helping young bodies develop normally, and older bodies age healthfully.
EPA: Eicosapentaenoic Acid and DHA: Docosahexaenoic Acid
- Found primarily in oily marine fish, but also some algae
- DHA plays a structural role in cell membranes, aiding in normal growth and development
EPA and DHA work together to:
- Support the normal growth and development of the brain, eyes (retina) and nervous system
- Help maintain a healthy cardiovascular system and normal triglyceride levels
Oily, marine fish such as wild salmon, tuna, sardines and anchovy, are the best source for Omega-3 EPA and DHA – and the only common source that contains both of these key fatty acids in abundance.
There is a third Omega-3 fatty acid, alpha-linolenic acid or ALA, which is found in some plant sources like flax or chia seed. While our bodies utilize ALA for energy production, we must further convert ALA to EPA and DHA before we can ultimately receive the healthful benefit from Omega-3s. Unfortunately, ALA does not readily convert to EPA and DHA, roughly 1% converts, so consuming preformed EPA and DHA from marine sources is the optimal way to ensure you receive the health benefits of Omega-3s.
ALA: Alpha-Linolenic acid
- Found in flax (linseed), hemp, chia seeds
- Is converted by the body to EPA and DHA
- Conversion rate is very low – less than 1%
- Not an optimal Omega-3 source for EPA and DHA
Fish (EPA and DHA) vs. Flax (ALA)
On the surface, flax appears to provide a high content of Omega-3. Every tablespoon of flax oil contains 6,900 mg of Omega-3, while every tablespoon of cod liver oil contains 2,800 mg. Fish oil provides Omega-3 as preformed EPA and DHA, which is what the body is looking for to modulate healthy responses in the body. Flax oil on the other hand provides Omega-3 in the form of ALA, which must then be converted to EPA and DHA.
Studies have shown that the conversion process is extremely inefficient. While the ability to transform ALA into EPA and DHA depends on the individual, research shows that humans convert approximately 1% of ALA into EPA and DHA. In other words, perhaps as much as 99 per cent — of ALA goes unused as an Omega-3 source. The good news is the body does use ALA for energy production, but if you are looking for benefits from Omega-3s, preformed EPA and DHA is essential.
The International Society for the Study of Fatty Acids and Lipids (ISSFAL) agrees that fish oil is the preferred source of Omega-3 over flax oil. The organization issued a statement that
“conversion of ALA to EPA is very low, and to DHA is even less — essentially negligible. These very low conversion rates mean that ALA cannot meet the body’s need for DHA.”
Fish (EPA and DHA) vs. Krill (EPA and DHA)
Purveyors of krill oil claim that, like fish oil, it provides both EPA and DHA, but is more absorbable than fish oil, due to the fact that it is bound to phospholipids. As a result, the Omega-3 in krill are purported to pass through the cell membrane easier than the Omega-3 in fish oil. These claims are not supported by recent science, as a study published in the journal Lipids in Health and Disease found that there is no significant difference in the bioavailability of Omega-3s from krill oil and fish oil.
A drawback of krill oil is the cost. It costs more to harvest and process krill and that cost gets passed on to consumers. A krill oil supplement can cost up to 10 times more than a fish oil supplement if you are trying to get enough EPA and DHA.
Good Fats vs. Bad Fats
Not all fat is bad. Good fats, known as polyunsaturated fatty acids (PUFAs), are dietary fats that help you maintain a healthy body and support normal function. PUFAs are a source of vital nutrients that your body cannot make on its own at significant levels; therefore, it is essential that you consume them in your daily diet.
Your body requires regular, daily intake of these good fats to function properly and stay healthy.
Good fats include:
- Omega-3: EPA & DHA, found in oily fish, fish oils, and algal oil; ALA found in flax
- Omega-6: grains & vegetable oils
- Omega-9: found in olive oil
Not all fats are healthy. While it may not be necessary to avoid bad fats altogether, it is important to limit your consumption of them.
Bad fats include:
- Saturated fats: dairy fat (butter, cream), lard and the visible fat on meats
- Trans fats: vegetable shortening and partially hydrogenated vegetable oils
Different global organizations recommend varying amounts of EPA and DHA, but most Omega-3 experts recommend that adults should consume at least 250 mg of Omega-3 EPA and DHA per day (equivalent to two fatty fish meals per week) to maintain overall good health and prevent deficiency.
Joint Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO) Expert Consultation on Fats and Fatty Acids in Human Nutrition (2010)
- Adults – 250 mg/day EPA/DHA
- Pregnant/lactating women – 250mg EPA + DHA/day plus 100-200mg DHA
ISSFAL (International Society for the Study of Fatty Acids and Lipids) 2004
- 500 mg/day EPA/DHA for adults for cardiovascular health
AHA (American Heart Association) 2002
- Two servings of fatty fish per week – for general health
- 1000 mg/day of Omega-3 EPA/DHA – patients with coronary heart disease
- 2000 to 4000 mg/day of Omega-3 EPA/DHA – patients with high triglycerides
USDA (US Dept of Agriculture) and HHS (Department of Health and Human Services)
- General population – Consume about 8 ounces per week of a variety of seafood, which provide an average consumption of 250 mg per day of EPA and DHA
- Pregnant and breast feeding women – It is recommended that women who are pregnant or breast-feeding consume at least 8 and up to 12 ounces of a variety of seafood per week, from choices that are lower in methyl mercury
- Adults – 250mg/day EPA/DHA
(note: g converted to mg for consistency)
- Joint WHO/FAO Expert Consultation on Diet, Nutrition and the Prevention of Chronic Diseases (2002: Geneva, Switzerland) Diet, nutrition and the prevention of chronic diseases: Report of a joint WHO/FAO expert consultation, Geneva, 28 January -- 1 February 2002. WHO technical report series 916.
- US Department of Health and Human Services; US Department of Agriculture. 2015-2020 Dietary Guidelines for Americans. 8th ed. Washington, DC: US Dept of Health and Human Services; December 2015. http://www.health.gov/DietaryGuidelines. Accessed December 16, 2015.