OMEGA-3 FATTY ACIDS
What does grass fed beef and fish have in common? Both are an excellent source of an essential fatty acid, omega-3, that is in short supply in the modern American diet.
There are two types of essential fatty acids (EFA) that are critical for human health and which cannot be manufactured by the body: omega-6 FAs and omega-3 FAs. Although they are similar, the two types are distinct. Since one type cannot be converted into the other, both must be present in the diet. Our ancestors evolved on a diet with a ratio of omega-6 to omega-3 of about 1:1. A massive change in dietary habits over the last few centuries has changed this ratio to something closer to 20:1 today in the U.S. (Omega-3 Information Service 2002; Pepping 1999). Ideally, intake of omega-6s should be no more than four or five times more than omega-3s. Researchers have recognized this imbalance as a major contributor to health problems such as heart disease, hypertension, diabetes, obesity, premature aging, some forms of cancer, autoimmune diseases such as arthritis and lupus, and depression (Larson 2002; Omega-3 Information Service 2002).
Grass-fed beef not only is lower in overall fat and in saturated fat, but it has the added advantage of providing more omega-3 fats, up to 7% of the total fat content (All Organic Food 2002). When cattle are taken off grass, however, and shipped to a feedlot to be fattened on grain, they immediately begin losing the omega-3s they have stored in their tissues. As a consequence, the meat from feedlot animals typically contains only 15 percent as much omega-3s as that from grass-fed livestock. Additionally, animals finished on grain have a dramatically different fatty acid profile, with an omega-6:omega-3 ratio of 14:1 or higher, compared to that of grass fed beef with an omega-6/omega-3 ratio as low as 0.16:1 (Iowa State University 2001; note that other studies show ratios ranging from this low to omega 6:omega-3 ratio of 3:1).
So how does grass fed beef compare to other protein sources for omega-3 concentration? Consider the following:
Chicken breast 0.09 mg/gram edible food
Red snapper 0.2
Grass fed beef 0.35
Pacific halibut 0.5
Rainbow trout (steelhead) 0.6
Pink Salmon 1.0
(Data for fish from Purdue University, data for chicken and beef from Rule et al 2002)
Benefits of Omega-3 in the diet
Prenatal and early infancy (up to 6 months) and young children
Insufficient omega-3s in the diet may increase the risk of premature birth and low birth weight (Simopoulous 1991; Uauy-Dagach and Valenzuela 1996). **references at bottom of page
Omega-3s are particularly important during the last three months of pregnancy and during early infancy for the proper development of the eyes, and the brain and nerves. (Carlson et al 1999; Omega-3 Information Service 2002).
Evidence is accumulating that inadequate levels of omega-3 FAs are associated with hyperactivity in children (Mitchell et al 1987; Stevens et al 1995).
Both preeclampsia and postpartum depression may be linked to a deficiency in omega-3s (Makrides and Gibson 2000).
Among women, higher consumption of fish and omega-3 fatty acids is associated with a lower risk of coronary heart disease, particularly deaths related to coronary heart disease (Hu et al 2002)
Women who consumed the most omega-3s were found to have only about half as many fatal heart attacks compared to those who consumed the least (Hu et al 1999)
Omega 3 supplementation has been shown to reduce blood triglyceride levels, a factor related to heart disease (Nestel et al 2002)
Omega 3 supplementation increases the elasticity of blood arteries, reducing risk of ischemic heart disease (Nestel et al 2002)
Increasing dietary omega 3 through the consumption of just 2 servings of fish per week was associated with about a 40% decrease in deaths from ischemic heart disease in a large prospective study of 20,000 physicians (Albert et al 1998)
After adjusting for age, smoking, and other cardiovascular risk factors, women who ate fish one to three times per month had a 7 percent lower risk than those who ate fish less than once per month. Women who ate fish once a week had a 22 percent risk reduction; those who ate fish two to four times a week had a 27 percent lower risk; and for those who ate fish five or more times per week, their risk of total stroke was reduced 52 percent (Hiroyasu et al 2001).
Autoimmune diseases (arthritis, lupus, certain kidney disorders, Crohn’s disease)
Research into the effect of fish oils on inflammatory conditions has found that the omega-3s help to damp down many of the body’s processes which create inflammation (Omega 3 Information Service 2002)
Daily supplementation with fish oils can markedly reduce the number of tender joints and increase the time before fatigue sets in, reducing or eliminating the need for pain relieving drugs (Fortin et al 1995; Geusens et al 1994; Kremer 2000).
Children who regularly eat fresh, oily fish have a four times lower risk of developing asthma than do children who rarely eat such fish (Hodge et al 1996)
Supplementation with 3.3 grams/day of fish oil markedly reduces breathing difficulties and other symptoms in asthma patients (Broughton et al 1997; Dry and Vincent 1991)
Inflammatory skin diseases (eczema, psoriasis)
Large doses (more than 3000mg a day) have proved effective in reducing redness, itching and scaling, though findings of studies with smaller amounts have been mixed. Omega-3 fish oils at these high levels should only be taken with the consent of a doctor (Omega-3 Information Service 2002).
Mental Illness and Cognitive Function Impairment
High intake of omega-3s have been linked to decreases in age-related memory loss and cognitive function impairment.
Omega-3s may lower the risk of Alzheimer’s disease, and significantly improve individuals suffering from Alzheimer’s (Levine 1997; Kalmijn 1997a, 1997b; Yehuda 1996)
Omega-3 supplementation has been successfully used to treat depression and schizophrenia (Omega-3 Information Service 2002)
Mercury Rising: Our Seafood Is Increasingly Contaminated With Toxins
More than just dioxins in food
Science News; May 2002; Environmental Science and Technology Online
The first extensive look at chemical contamination pathways in aquaculture systems points to fish meal and oils as primary sources of persistent organic pollutants (POPs) in farm-raised fish. The study, published on ES&T’s Web site under Research ASAPs (10.1021/es011287i), turned up a wide range of POPs, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ether (PBDE) flame retardants, and organochlorine pesticides in farm-raised and wild European Atlantic salmon, aquaculture feed, and fish oils. High levels of PCBs and evidence of recent usage of the pesticide DDT in the fish samples suggests that dioxins are not the only contaminants in foods that regulatory bodies should be concerned about. (read more)
Why you should be concerned about eating salmon
Seattle Times, September 2001
They swim in a floating mesh pen and leap in skittering displays of aerial acrobatics. More than 50,000 young Atlantic salmon fattening in the cool blue waters of the Canadian Pacific.
These fish have emerged in the past decade as the biggest source of salmon for the world’s seafood consumers. In just the past year, global farmed-salmon production increased 18 percent to reach 2.5 billion pounds, far outweighing the 1.65 billion-pound wild-salmon haul. (read more)
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