A large number of studies have shown that almost all synthetic pigments cannot provide nutrients to the human body, and some synthetic pigments can even harm human health, leading to decreased fertility, teratogenesis, etc., and some may even be converted into carcinogens in the human body. 
The coloring power of natural pigments is generally not as strong as that of synthetic pigments, and it is easier to fade or change color.
 natural pigments should be used instead of synthetic pigments.