Eating grapefruit after breakfast can help the body digest and absorb, clean the stomach, supplement the body's nutrition and refresh the mind. Grapefruit is an alkaline food, but it contains a lot of acidic substances. Pregnant women should not eat grapefruit on an empty stomach to avoid the acidic substances in grapefruit stimulating the gastric mucosa, causing a large amount of gastric acid secretion and damaging gastric function.