Though grapes are highly nutritious, excess consumption can have the following side effects;

Stomach upset

 Grapes are high in salicylic acid, which can cause stomach pain, bloating, inflammation, and indigestion caused by the seeds. It’s also high in insoluble fibers that can trigger IBS as they inflame the gastrointestinal tract.

Weight gain

Consuming excess grapes can increase obesity and weight gain risks as they are high in calories.


The high simple sugars in grapefruits and grape juices or eating unpeeled grapes from new locations may result in diarrhea.

Other potential side effects include grape allergy, headaches, and dry mouth.

Are grapes generally healthy to eat? Why or why not? Who might they be good for, and who might they not be good for (like people with diabetes)?

Generally, when eaten in moderate amounts, grapes are healthy fruits loaded with minerals and vitamins such as potassium, vitamin C, antioxidants, etc. The body needs these to boost the immune and lower risk of diseases.

All healthy people can consume grapes. However, people with diabetes and IBS should limit their grape intake.

Latest posts by Elena Ognivtseva (see all)

Nutritionist, Cornell University, MS

I believe that nutrition science is a wonderful helper both for the preventive improvement of health and adjunctive therapy in treatment. My goal is to help people improve their health and well-being without torturing themselves with unnecessary dietary restrictions. I am a supporter of a healthy lifestyle – I play sports, cycle, and swim in the lake all year round. With my work, I have been featured in Vice, Country Living, Harrods magazine, Daily Telegraph, Grazia, Women's Health, and other media outlets.

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