Research

Micronutrients & recovery

GLP-1 therapy for obesity increases the risk of nutritional deficiencies (e.g., iron, calcium, vitamins A, D, E, K, B1, B12, C) due to significant reductions in caloric intake and potential GI side effects that impair absorption.

Because GLP-1s make you eat much less, you might not get enough essential vitamins and minerals. Watch for signs like fatigue, hair loss, or poor wound healing. Prioritize nutrient-dense foods (vegetables, lean proteins, whole grains) and discuss with your doctor whether you need specific supplements, especially if your calorie intake is very low.

GoodSupportsHIGH confidence
This large, rapid reduction can lead to insufficient intakes of essential vitamins and minerals... Examples nutrients of concern include iron, calcium, magnesium, zinc, and vitamins A, D, E, K, B1, B12, and C.
Dariush Mozaffarian et al. · American Journal of Clinical Nutrition · 2025

Why this rating

Based on clinical observations and trial data cited.

Source

Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society

Dariush Mozaffarian et al. · American Journal of Clinical Nutrition · 2025

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