The U.S. Preventive Services Task Force (USPSTF) concludes that the current evidence is insufficient to assess the balance of benefits and harms of the use of multivitamins, single- or paired-nutrient supplements (except β-carotene and vitamin E) for the prevention of cardiovascular disease or cancer. The USPSTF recommends against the use of β-carotene or vitamin E supplements for the prevention of cardiovascular disease or cancer because of a proven lack of benefit accompanied by an increased risk. The guidance applies to primary prevention in healthy adults without nutrient deficiencies, with the exception of women who are pregnant or may become pregnant, a group that “should take a daily supplement containing folic acid to help prevent neural tube defects.” The guidance is consistent with that from other organizations, including the National Institutes of Health, the Academy of Nutrition and Dietetics and the American Heart Association.美国预防医学工作小组（USPSTF）的结论是，除了β-胡萝卜素和维生素E，目前的证据不足以评估使用多种维生素，单一或者配对营养补充剂以预防心血管疾病或癌症的利弊。USPSTF的建议反对使用β-胡萝卜素或维生素E补充剂以预防心血管病或癌症，因为已证明其无益或有害。该建议适用于无营养缺乏的健康成人的一级预防， 孕妇或可能怀孕的妇女除外，其“应每天服用含有叶酸的补充剂，以助预防神经管缺陷。”该建议与其他组织，包括国立卫生研究院，美国心脏协会，以及营养和饮食学院的建议是一致的。
