Fish oil can be used temporarily as a dietary supplement for EPA and DHA, but it is not recommended for long-term use, and it is still recommended to supplement the appropriate nutrients from the diet. So fish oil can be taken occasionally, not long-term. Fish oil is a kind of oil extracted from fatty fish, rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as a variety of n-3 series polyunsaturated fatty acids. Therefore, it can be used as a dietary supplement for EPA and DHA when the diet is not balanced. However, it is not recommended to consume fish oil for a long period of time to obtain the corresponding nutrients. We can get enough EPA and DHA through scientific diet. α-linolenic acid can be converted to EPA and DHA in human body, that is, as long as a person can consume enough α-linolenic acid, there is no need to supplement fish oil for a long time. Alpha-linolenic acid in perilla oil, flaxseed oil, soybean oil, canola oil a variety of fats and oils are present. One of the main components contained in perilla oil is alpha-linolenic acid, with a content of about 67%. Food is the best source of nutrients the vast majority of the time.