Omega-3 fatty acids are healthy fats that reduce inflammation, inhibit cancer development and protect our blood vessels. There are long-chain and short chain fatty acids. Short-chain omega-3 fats are found in some green vegetables, walnuts, and flax, chia, and hemp seeds. The basic building block of short-chain omega-3 fat is alpha-linolenic acid (ALA). Our bodies are only capable of converting a small amount of these short chain fats to long-chain omega-3 fats, called docoshexanoic acid (DHA) and eicosapentaenoic acid (EPA).
Studies show that people have varying ability to convert ALA into DHA and EPA. Apparently, some people eating sufficient ALA from greens, seeds and walnuts can achieve adequate levels while others cannot. Men generally convert less than women. Conversion of ALA by the body to these longer-chain fatty acids is inefficient: < 5-10% for EPA and only 2-5% for DHA.1
DHA is one of the crucial building blocks of human brain tissue. It has been shown to protect against dementia, depression, inflammatory diseases, attention deficit and hyperactivity disorder (ADHD), allergies, and to offer significant benefits for overall cardiovascular health.
Early in life, DHA is supplied via the placenta and from breast milk. While adequate DHA is particularly important for pregnant and nursing women and young children, it is beneficial for all ages!
- Improves your child's intelligence
- Aids depression and Attention Deficit Disorder
- Improves memory
- Important for brain and eye development
- Promotes smoother skin; prevents wrinkles
- Helps prevent heart disease and arthritis
- Lowers risk of Alzheimer's and senior dementia
- Lowers "bad" cholesterol
These long-chain omega-3 fatty acids are also produced by marine algae which serve as the source of DHA and EPA in fish. Although, fish is a good source of EPA and DHA, unfortunately, it's one of the most polluted foods which we eat. Therefore, it can not be considered a safe source of these healthy fats.
Fish have been shown to contain fat soluble petrochemicals, such as PCB's and dioxins as a result of the dumping of toxic waste and raw sewage into our oceans. Fish also contains mercury. According to the Center for Disease Control, 1 in 12 women of childbearing age in the United States have unsafe mercury levels (and the CDC's threshold for safety is high). Multiple studies have illustrated most of the body's mercury load comes from the consumption of fish.
For these reasons, I recommend consuming little or no fish. If you choose to consume fish, try to stay away from those high in fat and known to be high in mercury such as shark, swordfish, mackerel, pike, tuna, snapper, lobster, grouper, sea bass and bluefish. Instead, use the lower fat (less polluted) fish such as flounder, sole, haddock, scallops, squid, trout, hake, ocean perch, shrimp and tilapia.
Some nutritional advisors encourage consuming high amounts of flax seed oil to promote the conversion of enough DHA. I do not agree. First of all, flax seed oil is an empty calorie food with little or no vitamins, minerals, phytochemicals and flavonoids that were present in the original seeds. Furthermore, we have a significant collection of data that indicates that the consumption of high doses of ALA from flax oil may increase, not decrease the risk of prostate cancer.1 In contrast, flax seed consumption has been shown in multiple studies to lower the risk of both breast cancer and prostate cancer.3
I prefer people not consume much fish to assure sufficient consumption or conversion of omega-3s. Since the ability to self-convert short chain ALA into long-chain DHA is so variable from person to person, I recommend a mixture of natural omega-3 containing plants plus some extra plant-derived DHA. I advise people obtain their omega-3 fats by consuming the cleaner, plant sources such as walnuts, flax, chia, and hemp seeds and by also taking a daily DHA supplement like my DHA Purity. My DHA Purity is a laboratory cultivated DHA product made from microalgae. It is a pure form of DHA without environmental contamination or unnecessary disruption of our ocean life.
1. Davis, B. C. and P. M. Kris-Etherton. Achieving optimal essential fatty acid status in vegetarians: current knowledge and practical implications. Am J Clin Nutr 2003;78(3 Suppl):640S-646S. Brenna, J. T. Efficiency of conversion of alpha-linolenic acid to long chain n-3 fatty acids in man. Curr Opin Clin Nutr Metab Care 2002;5(2):127-32.
2. Brouwer IA, Katan MB, Zock PL. Dietary alpha-linolenic acid is associated with reduced risk of fatal coronary heart disease, but increased prostate cancer risk: a meta-analysis. J Nutr 2004 Apr;134(4):919-22.
3. Demark-Wahnefried W, Price DT, Polascik TJ, et al. Pilot study of dietary fat restriction and flaxseed supplementation in men with prostate cancer before surgery: exploring the effects on hormonal levels, prostate-specific antigen, and histopathologic features. Urology 2001 Jul;58(1):47-52.
Image credit: niznoz