Best General Health Supplements 2026

How to Choose a General Health Multivitamin

A multivitamin can help fill gaps in your diet, but it is not proven to prevent disease. The US Preventive Services Task Force (2022) found the evidence insufficient to say whether multivitamins prevent heart disease or cancer. It recommends against beta-carotene and vitamin E supplements for that purpose, because beta-carotene raised lung cancer rates in smokers and people exposed to asbestos. In the VITAL trial of about 26,000 adults, 2,000 IU of vitamin D a day did not lower cancer or heart events.

What to look for

• Vitamin D: the NHS says everyone should consider 10 micrograms (400 IU) a day in autumn and winter. People who get little sun, or who have dark skin, should consider it all year. See our vitamin D3 page.
• Folic acid: if you could become pregnant, take at least 400 micrograms a day. ACOG says folic acid is the only form of folate proven to prevent neural tube defects. The CDC says people with MTHFR gene variants can process folic acid normally.
• Iodine: the adult RDA is 150 micrograms. The American Thyroid Association advises against iodine or kelp supplements with more than 500 micrograms a day.
• Iron: take it only if a blood test shows you need it. The NHS says 17 mg a day or less is unlikely to cause harm.
• Zinc: the NHS advises no more than 25 mg a day from supplements. See our zinc page.
• Magnesium: NCCIH gives 350 mg a day as the adult upper limit from supplements.
• Selenium: the NHS says 350 micrograms a day or less from supplements is unlikely to cause harm; too much causes hair and nail loss. More on our selenium page.

Red flags to avoid

• Beta-carotene or vitamin E sold for disease prevention.
• Vitamin A: the NHS says more than 1.5 mg (1,500 micrograms) a day over many years may weaken bones.
• High-dose iron without a confirmed deficiency.
• "Superfood blends" that replace measured vitamins with unstandardized powders.
• Claims that a multivitamin prevents heart disease, cancer or dementia.

What we rank on

• Doses that meet daily needs and stay within UK and US upper limits.
• Folic acid at 400 micrograms or more.
• No beta-carotene megadoses.
• Third-party testing and full label disclosure.
• We penalize proprietary blends and disease-prevention claims.

Sources:

• USPSTF 2022: Vitamin, mineral and multivitamin supplementation
• Manson 2019, VITAL vitamin D trial
• NHS: Vitamin D
• ACOG: Healthy eating during pregnancy
• CDC: MTHFR gene variant and folic acid
• ATA: Risks of excess iodine
• NHS: Iron
• NHS: Vitamins and minerals, zinc
• NHS: Vitamin A
• NCCIH: Sleep disorders and complementary approaches (magnesium limit)

General health multivitamins are scored on micronutrient forms (bioavailable variants preferred), dose adequacy relative to RDAs without unnecessary excess, third-party testing, and appropriate iron and vitamin A levels. Proprietary blends and unvalidated "superfood" additions reduce the score.