Photosensitive foods are those that are likely to cause solar dermatitis. Generally speaking, photosensitive foods are digested and absorbed, and the photosensitive substances contained in them will enter the skin, which will react with sunlight if exposed to bright light. If exposed to bright light at this time, it will react with the sunlight. This will lead to redness, swelling and rash of the exposed skin, accompanied by obvious itching, burning or stinging sensation. Some vegetables with high chlorophyll content and wild vegetables (ashwagandha, bitter greens) are photosensitive foods. Common photosensitive foods include ashwagandha, marjoram, purple clover, snow lettuce, fennel, amaranth, capers, celery, radish leaves, spinach, raised wheat, parsley, safflower herb, rape, mustard, figs, citrus, lemon, mango, pineapple, etc. In addition, “photosensitive seafood” including snails, shrimp, crabs, mussels, etc., also contains photosensitive substances, also need to pay attention to. Whether or not these foods can cause solar dermatitis depends on the individual’s constitution, so those with allergies should try to eat them carefully. In addition, certain Chinese herbs, such as dahurica, zhu huang, thorny mustard, bupleurum and sage, also contain photosensitizing substances. Photosensitizing western medicines: sulfonamides, aspirin, sodium salicylate, tetracycline, paracetamol, Librium, oral contraceptives, estrogen, etc. also need to be noted. Exogenous photosensitizers include skin daily contact such as cosmetic fragrances (bergamot oil, lemon oil, sandalwood oil, musk, ambergris, etc.), preservatives, aniline and aniline derivatives, dyes, etc.; occupational exposure or external use on the skin such as tar, asphalt and some moss-like plants, bone fungus, dahurica, coumarins, etc. Endogenous photosensitive substances such as porphyrins cause photosensitivity reactions, mainly seen in porphyrias. Vitamin C can shorten the cycle of pigmentation, block the formation of melanin and indirectly reduce pigmentation, and at the same time, it can remove free radicals in the body, which has antioxidant and anti-aging effects. In addition, vitamin B, especially niacinamide, or betacarotene should be taken orally to reduce the sensitivity of skin to sunlight.