What evidence-based supplements are recommended for daily use?

Evidence-Based Daily Supplements for General Adult Population

For most healthy adults, routine vitamin and mineral supplementation beyond a standard multivitamin is not supported by evidence, with the critical exception of vitamin D at 1,000-2,000 IU daily, which has strong safety data and addresses widespread deficiency. 1

Core Recommendation: Vitamin D Supplementation

Vitamin D is the single most evidence-based supplement for daily use in adults, with the following dosing strategy:

Standard Daily Dosing

• Adults under 70 years: 600-1,000 IU daily 2, 3
• Adults 71+ years: 800-1,000 IU daily 2, 4
• Higher-risk populations (obesity, dark skin, limited sun exposure, malabsorption): 2,000 IU daily 5, 6

Target Serum Levels

• Minimum adequate: 20 ng/mL (50 nmol/L) 2, 4
• Optimal for broader health benefits: 30-44 ng/mL 1, 4

Safety Profile

• Daily doses up to 4,000 IU are considered safe long-term 4, 7
• Doses of 2,000 IU daily for several years show no significant safety concerns in large RCTs 5
• Vitamin D3 (cholecalciferol) is strongly preferred over D2 (ergocalciferol) 1, 4

Calcium Supplementation: Conditional Recommendation

Calcium supplementation should only be added if dietary intake is insufficient to meet targets:

Dosing Strategy

• Adults 19-50 years: 1,000 mg total daily (diet + supplements) 1, 2
• Adults 51+ years: 1,200 mg total daily (diet + supplements) 1, 2
• Divide doses: No more than 500-600 mg per dose for optimal absorption 2

Critical Caveats

• Calculate dietary calcium intake first—many patients already consume adequate amounts from food 2
• Dietary calcium is preferred over supplements due to lower kidney stone risk 2
• Calcium supplements modestly increase kidney stone risk (1 case per 273 women over 7 years) 2
• Maximum total intake should not exceed 2,500 mg daily 1

What NOT to Supplement Routinely

Antioxidants: Not Recommended

The Institute of Medicine concluded that megadoses of antioxidants (vitamin C, vitamin E, selenium, beta carotene) are not demonstrated to protect against cardiovascular disease, diabetes, or cancer, and may cause harm including diarrhea, bleeding, and toxic reactions. 1

• Vitamin E supplementation (400 IU/day for 4.5 years) showed no benefit in the Heart Outcomes Prevention Evaluation Trial 1
• Beta carotene supplementation unexpectedly increased lung cancer incidence in two trials 1

General Multivitamins: Limited Indications

Routine multivitamin supplementation is only advisable for specific high-risk groups:

• Elderly individuals 1
• Pregnant or lactating women 1
• Strict vegetarians 1
• Individuals on calorie-restricted diets 1

Other Minerals: No Routine Supplementation

There is no clear evidence of benefit from routine supplementation of chromium, selenium, zinc, or other minerals in people without underlying deficiencies. 1

Special Population Considerations

High-Risk Groups Requiring Vitamin D Without Testing

• Dark-skinned or veiled individuals with limited sun exposure: 800 IU daily 1, 4
• Institutionalized elderly: 800 IU daily or equivalent intermittent dosing 1, 4
• Patients on glucocorticoids (≥2.5 mg/day for >3 months): 800-1,000 IU daily 2

Documented Vitamin D Deficiency (<20 ng/mL)

• Initial correction: 50,000 IU weekly for 8 weeks 2, 4
• Maintenance: 800-1,000 IU daily thereafter 2, 4

Critical Pitfalls to Avoid

Vitamin D Dosing Errors

• Do not confuse recommended daily intake (600-800 IU) with maximum safe dose (4,000 IU)—the former is for general health, the latter is the safety ceiling 4
• Avoid single massive doses: 300,000-500,000 IU annually increases fall and fracture risk 4, 7
• Doses below 400 IU/day are ineffective for fracture reduction 4

Calcium Supplementation Errors

• Do not supplement without calculating dietary intake first 2
• Do not exceed 500-600 mg per dose 2
• Do not use calcium carbonate without food—it requires gastric acid for absorption 2

Antioxidant Supplementation

• Do not prescribe megadoses of vitamins C, E, or beta carotene for disease prevention 1
• High-dose antioxidants may lead to adverse effects including increased cancer risk 1

Practical Implementation Algorithm

Step 1: Assess vitamin D risk factors (age >65, dark skin, limited sun exposure, obesity, malabsorption)

• If present: Start 1,000-2,000 IU daily 5, 6
• If absent: Start 600-800 IU daily based on age 2, 3

Step 2: Calculate dietary calcium intake

• If <1,000 mg/day (age <51) or <1,200 mg/day (age 51+): Add calcium supplement in divided doses 2
• If adequate: No calcium supplementation needed 2

Step 3: Consider multivitamin only if patient falls into high-risk category (elderly, pregnant, vegetarian, calorie-restricted) 1

Step 4: Monitor 25(OH)D levels after 3 months if taking >1,000 IU daily, then every 1-2 years 4