Grapefruit affects liver P450 enzyme activity and reduces the effectiveness of birth control pills. Pomelo is very nutritious, which is rich in protein, vitamin C, organic acids and calcium, phosphorus, sodium, magnesium and other nutrients, can provide nutritional value for the human body, and to maintain the normal physiological function of the body. Need to pay attention to the grapefruit allergy crowd should not eat, so as not to cause allergic reactions, as well as high blood sugar, diabetic people also need to pay attention to moderate consumption. In addition, grapefruit will affect the liver P450 enzyme activity, reducing the effect of contraceptive pills. Therefore, avoid eating grapefruit during taking contraceptive pills. If the patient has thrombosis, hypertension and other diseases, it is usually not recommended to take contraceptive pills, so as not to affect the body. It is usually recommended to choose a barrier for contraception, which means using condoms. Oral short-acting contraceptives can be used for a long time up to the age of 40 if there are no contraindications. If you need to use the drug, you should take it under the guidance of a professional doctor, and not blindly use it on your own to avoid adverse consequences.