DHA, scientifically known as docosahexaenoic acid, is a very important unsaturated fatty acid for the human body, belonging to the ω-3 unsaturated fatty acid family of important members. Research has confirmed that DHA is a major component of the growth and maintenance of cells in the nervous system, and is an important component of the brain and retina, containing up to 20% in the human cerebral cortex and the largest proportion in the retina of the eye, accounting for about 50%, and is therefore essential for the intellectual and visual development of fetal infants. DHA is not synthesized by the body itself, it depends on external supplementation, and is easily decomposed in the stomach acid, so it is best to take with meals or before meals. By the age of 6 years old is generally close to the level of adults, and then supplementation is not very useful. Breast milk, egg yolk and fish are all good sources of DHA. In addition, the amount of DHA required for different ages varies, the older the baby, the more DHA is required. Excess DHA can have side effects, such as causing low immunity. Therefore, it is important to follow your doctor’s advice on how to take it.