No vitamin supplementation is indicated to reduce the risk for cardiovascular disease and cancer in this patient. Although one third of U.S. adults use supplemental vitamins, the U.S. Preventive Services Task Force (USPSTF) has concluded that there is insufficient evidence to assess the balance of benefits and harms of vitamin use, including use of vitamin A, vitamin C, and antioxidant combinations, in the prevention of cardiovascular disease and cancer. This recommendation applies to multivitamin preparations and to single- or paired-vitamin preparations, with the exception of vitamin E and β-carotene. Because of potential adverse effects associated with their use, the USPSTF specifically recommends against the use of vitamin E and β-carotene for these purposes. This patient should be advised that taking supplemental vitamins or minerals will not lower his risk for cardiovascular disease and cancer. Instead, he should continue to consume a balanced diet that includes fruits and vegetables and to exercise regularly.

Vitamin supplementation should be used in treating known deficiencies or in clinical situations in which it has been shown to be effective, such as vitamin D supplementation in patients with osteoporosis.