DHA, called docosahexaenoic acid in Chinese, is an omega-3 polyunsaturated fatty acid, mainly found in deep-sea fish, seaweed and fish oil supplements. Involves the metabolic process of three enzymes, the conversion efficiency is relatively low; 2, food sources: DHA is widely found in seafood, mackerel, salmon, mahi-mahi in rich content, in the marine microalgae DHA content of up to 35% or more. Lack of DHA can cause growth retardation, mental retardation, abnormal skin scaling, etc.. Since the human body can not synthesize DHA by itself, it can usually meet the needs through the intake of fish, seafood or nutritional supplements, but it should be noted that DHA is not the more intake the better, during the growth and development, if you need to supplement DHA, you should make appropriate supplements according to the doctor’s advice, such as DHA is sufficient, there is no need to consume excessive amounts to avoid burdening the body.