Is IgG useful for weight loss?

IgG-based food sensitivity tests are often marketed for weight loss, but the scientific evidence is weak. IgG antibodies indicate immune exposure, not necessarily intolerance or inflammation. Studies showing significant weight loss from IgG-guided elimination diets are scarce and often lack rigorous controls. Major health organizations do not recommend these tests for weight management. Instead, evidence-based approaches like calorie restriction, exercise, and behavioral changes are effective. IgG tests may lead to unnecessary dietary restrictions and nutritional deficiencies. Conclusion: marketing claims outweigh the evidence.