🔵 Early supportive evidence (pilot human study)

Study at a glance

• Participants: 22 professional athletes
• Condition: Gastrointestinal discomfort
• Study type: Pilot study (no control group)
• Duration: 3 months

What was done

Athletes with digestive symptoms took a food-specific IgG blood test. They then followed a personalised diet removing foods identified by the test, while maintaining their normal training and calorie intake.

What improved

After 3 months:

• Indigestion symptoms reduced from 0.5 to 0.3 (around a 40% reduction)
• Overall digestive symptoms also improved, showing a clear positive trend
• Allergy-related symptom scores reduced from 4.9 to 3.1 (around a 35–40% reduction)

Body composition and recovery also changed:

• Body fat decreased from 14.9% to 13.2% (around a 10–12% relative reduction), while body weight remained stable
• Heart rate recovery improved, with lower heart rates measured at both 2 and 3 minutes after exercise

Food-specific IgG levels also reduced across several foods removed from the diet, including gluten, cow's milk and eggs.

In practical terms, this means athletes experienced less digestive discomfort, fewer symptoms, and improved recovery after exercise.

Key takeaway

Removing foods identified by IgG testing was associated with:

• ~40% reduction in indigestion symptoms
• ~35% reduction in allergy-related symptoms
• Improved recovery after exercise

What this means

This study suggests that removing foods identified by IgG testing may help reduce digestive symptoms, even in highly trained individuals. Improvements in recovery and body composition may reflect better overall physiological balance.

Important to know

This was a small pilot study without a control group, so the results are encouraging but not definitive.

🔵 Evidence strength

Early supportive evidence (pilot human study)

Full citation

Kostić-Vučićević et al. 2017 Med Sport study

Kostić-Vučićević M, Dikic N, Andjelkovic M, et al.
Food elimination based on immunoglobulin G antibodies improves gastrointestinal symptoms and sport performance in professional athletes.
Medicina dello Sport. 2017;70(4):480–494.

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