The harms of eating coriander are:

1. Formation of sun spots: Coriander is a photosensitive food. Excessive consumption of coriander during the day may cause photosensitivity reactions after exposure to the sun. It can cause pigmentation and lead to sun spots.

2. Aggravation of odor: Because coriander contains some volatile oils, some people may easily stimulate the body to sweat after excessive consumption of coriander, resulting in aggravation of body odor, such as aggravation of body odor.

3. Affect medicinal properties: As a medicinal material in traditional Chinese medicine, coriander has a certain auxiliary effect on promoting blood circulation and accelerating metabolism. However, for patients who are taking traditional Chinese medicine, try not to eat too much coriander, as the medicinal properties may conflict, which is detrimental to the recovery of the condition.

4. Allergy: Because coriander is highly irritating to the human body, some people with allergies may have allergic reactions such as vomiting and eczema if they consume excessive amounts of coriander.

5. Inducing diseases: Because coriander is also a kind of hair-raising substance, it may induce diseases such as asthma, dermatitis, rhinitis, and skin diseases.

Generally, eating coriander in moderation will not have any obvious effects or disadvantages, but eating too much coriander will cause the above disadvantages.