Eating red grapes will not cause internal heat.
Traditional Chinese medicine believes that it is neutral in nature, replenishes qi and blood, strengthens muscles and bones, and has the effects of clearing blood and heat and diuresis. It is a cooling fruit, so eating some red grapes in moderation will not cause internal heat.
Red grapes have astringent effects and can be used to stop diarrhea when consumed. However, eating red grapes in hot weather will also astringe the heat and prevent it from dissipating easily, causing internal heat to accumulate, causing dry throat and sore throat in those who eat too much, showing symptoms similar to getting angry. Patients with constipation and diabetes should not eat too much.