Nutrition

June 16, 2008

Demystifying Omega-3 Fats

What’s the world’s most perfect food source? A good case can be made that it’s wild-caught cold-water fish such as salmon, mackerel, and trout. Not only are these fish high in quality protein, but they are replete in omega-3 fats. What’s so special about omega-3’s? Well, first off they are essential nutrients, meaning 1) they cannot be manufactured in the body and 2) they are required to avoid disease.

The benefits of consuming adequate omega-3’ fats are numerous. They help to improve cell signaling, enhance skin, hair and nails, and regulate important hormone-like compounds called eicosanoids. Perhaps their most important health-related function is their positive effect on the cardiovascular system. Not only do they inhibit the production of LDL (the “bad” form of cholesterol that has been implicated in the formation of atherosclerotic plaques), but they increase the output of HDL (the “good” cholesterol). This explains why replacing saturated fats with omega-3s on a calorie-for-calorie basis has been shown to reduce the risk of cardiovascular mortality by as much as 70 percent.

Omega-3 fats are also extremely important from a body composition standpoint. Because of their utility on cells, the body prefers to use Omega-3’s to fuel cellular functions and won’t store them as fat until these functions are satisfied. Specifically, they act as fuel partitioners, directing fatty acids away from storage and towards oxidation. One of the ways this is accomplished is through enzyme regulation, increasing the activity of fat burning enzymes and suppressing the activity of fat storing enzymes. The net effect is better fat metabolism and hence an improved body composition.

Additionally, Omega-3’s increase levels of a class of fat burning compounds called uncoupling proteins (UCPs). UCPs act on various bodily tissues to heighten thermogenesis, allowing calories to be burned off immediately as heat rather than stored as fat. Unfortunately, these substances are inhibited in many people, especially in those who are overweight. By revving up UCP activity, Omega 3’s shift your body into a fat burning mode, promoting a leaner physique.

In addition to cold water fish, omega-3’s can be found in high amounts in flax oil—the prime choice for vegetarians. Soy, walnuts, and hemp oil also contain modest amounts of omega-3 fats. Most people, however, do not take in enough of these food sources to satisfy omega-3 requirements. Worse, they consume an abundance of omega-6 fats which compete with omega-3’s for desaturation as well as producing pro-inflammatory eicosanoids that, unless counterbalanced by anti-inflammatory eicosanoids produced by omega-3’s, can result in a plethora of health issues.

 If you’re not getting enough omega-3’s, it may be beneficial to consume fish oil supplements. They come in capsule form (usually gel caps) and should be taken at mealtime. Although no specific guidelines have been set on for intake, a general guideline is to consume one gram for every 25 pounds of bodyweight (each capsule is usually one gram). It’s generally best to consume half the dose in the morning and the other half at night.

 Remember, though, that omega-3’s—like all dietary fats—are calorically dense. In order to realize positive changes in body composition, you need to make sure that total caloric intake is within your metabolic range. Calories do count and you can’t lose body fat if intake is greater than expenditure. What’s more, high doses of omega-3’s can potentially increase bleeding time. Check with your physician if any concerns exist.

Stay Fit!

Brad

TAGS: omega-3, omega-6, omega fats, fish oil, flaxseed oil, flax oil, UCP, uncoupling proteins, thermogenesis, eicosanoids