Fish are considered one of the best sources of DHA, but unfortunately, the EPA warns that pregnant women must watch their fish consumption because many fish contain harmful levels of mercury.

鱼类被认为是DHA的一个最好来源，但不幸的是，美国环保局警告说，怀孕妇女必须提防她们对鱼的消费量，因为许多鱼类含有危害程度的汞。

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Although human can convert alpha-linolenic acid(ALA)to EPA and DHA, the conversion rate is so low, you need eat a lot of food contain ALA, that's make it impractical.

虽然人体可以自动将 α-亚麻酸（ALA） 转换成 二十碳五烯酸（EPA） 和 二十二碳六烯酸（DHA） ，但转换率很低，人们需要食用大量含有 α-亚麻酸（ALA） 的食品才行，这种做法可行性不高。

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So they tested a fish-oil capsule with a high ratio of EPA to DHA, providing 1, 050 milligrams per day of the former and 150 mg per day of the latter.

于是他们测试了一种EPA和DHA含量很高的鱼油胶囊，这种胶囊每天能够提供1050毫克epa和150毫克dha。

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Because only a small percentage of ala is converted into EPA and DHA inside the body, it may not have the same heart benefits, cardiologists say.

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If you want omega-3s for your heart, read the fine print and look for products with EPA or DHA. Kashi says people don't get enough omega-3 and that it makes no specific health claims.

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Research suggests that DHA and EPA are only effective for bipolar disorder when they are used in combination.

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