What are the recommended supplements for a female seeking to gain weight in a healthy manner?

Healthy Weight Gain for Females: Evidence-Based Supplement and Nutrition Recommendations

For non-pregnant females seeking healthy weight gain, there is no clear evidence that nutrition supplements (such as herbs, botanicals, high-dose vitamins, minerals, amino acids, or enzymes) are effective for weight management, and most trials evaluating these products are of low quality and at high risk for bias. 1

Why Supplements Don't Work for Weight Gain

The most recent and highest-quality guideline evidence from the American Diabetes Association (2024) systematically reviewed nutrition supplements for weight management and found that despite widespread marketing claims, high-quality published studies show little or no weight change benefits from supplementation. 1 This represents the strongest available evidence on this topic and should guide clinical decision-making.

Evidence-Based Approach to Healthy Weight Gain

Primary Strategy: Increase Energy Intake Through Whole Foods

The most effective approach is to increase caloric intake by 20-30% above baseline energy needs through nutrient-dense whole foods, targeting approximately 0.5 kg weight gain every 7-10 days. 1

• For someone consuming 2000 kcal/day, this represents a gradual increase of 200-600 kcal/day accomplished over several months 1
• Focus on a diet rich in fruits, vegetables, whole grains, fish, lean protein, legumes, nuts, and seeds 1
• Prioritize healthy fats from polyunsaturated sources rather than saturated fats 1

Protein Requirements for Weight Gain

• Adequate protein intake is essential for gaining lean body mass rather than just fat mass 1
• Target protein intake should be individualized based on activity level and body composition goals 1

When Vitamin/Mineral Supplementation IS Appropriate

While supplements don't cause weight gain directly, correcting deficiencies may improve overall health and appetite:

• Iron supplementation may be beneficial if deficiency is documented, as iron deficiency can affect energy levels 1
• Vitamin B12 supplementation should be considered in at-risk populations with documented deficiency 1
• Vitamin D supplementation may be appropriate if levels are low 1

These should only be used to correct documented deficiencies, not as weight gain agents. 1

Critical Pitfalls to Avoid

Dangerous Practices to Reject

• Avoid very-low-calorie meal replacement products (800-1000 kcal/day), as these are designed for weight loss and carry high risk of complications including electrolyte abnormalities, severe fatigue, and cardiac arrhythmias 1
• Do not use unregulated herbal products or botanical supplements, as they lack standardization, vary in active ingredient content, and pose risks including drug interactions 2
• Reject marketing claims for "weight gain supplements" that lack scientific evidence 1

Medication Considerations

If you are taking medications, be aware that certain drugs affect weight:

• Weight-promoting medications include some antipsychotics (olanzapine, clozapine, quetiapine), certain anti-epileptics (gabapentin, pregabalin, valproic acid), and oral glucocorticoids 1
• Weight-neutral alternatives may be available depending on your medical condition 1
• Discuss medication effects on weight with your healthcare provider 1

Monitoring and Safety

• Weigh yourself weekly on the same scale, at the same time, wearing similar clothing to track progress accurately 1
• Monitor for adequate energy intake through food records to ensure you're meeting caloric goals 1
• Seek evaluation if unintentional weight loss occurs or if you cannot gain weight despite adequate caloric intake, as this may indicate underlying medical conditions 1

Special Considerations for Athletes

For female athletes specifically seeking weight gain:

• Energy availability should target at or greater than 45 kcal/kg of fat-free mass 1
• Weight gain in exercising women without clinical eating disorders has been observed to include gains in fat-free mass (muscle), not just fat 1
• Combine increased caloric intake with appropriate resistance training for optimal body composition changes 1

The Bottom Line

Focus on increasing whole food intake by 200-600 calories per day through nutrient-dense sources rather than relying on supplements, which lack evidence for effectiveness in weight gain. 1 The only supplements with proven benefit are those correcting documented vitamin or mineral deficiencies (iron, B12, vitamin D), which should be verified through laboratory testing before supplementation. 1