Hemp also has value as a food source, as its seeds provide the ideal balance between Omega 3 and Omega 6 oils for humans.

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Principal investigator Harvey Murff says many Americans consume far more omega-6 fatty acids, and one aim is to determine a healthy balance of omega-3 and omega-6 fatty acids.

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Supplements with omega-3 and omega-6 fatty acids may be of some benefit -- in some children.

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And some, like omega-3 and omega-6 fatty acids, are necessary, because the body can't make them.

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Spielmann says omega-3 and omega-6 fatty acids are essential for optimal brain development, the best sources for the baby being breast milk or whole milk.

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One is that a product can now claim to be high in long-chain omega-3s, yet be of questionable value because it also contains high levels of omega-6 fatty acids.

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The American Heart Association recommends consuming both omega-3 fatty acids, found in cold-water fish like salmon and canola oil, and omega-6 fatty acids, found in nuts, seeds and vegetable oils such as corn oil.

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"We gave them about 1.6 grams of omega-3 per day, which is 10 times more than people would normally have, " he said.

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They say consuming 250 milligrams of omega-3 fatty acids a day -- t he equivilant of 6 ounces a week of wild salmon or other oily fish -- could prevent heart disease.

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