Foods to Avoid with G6PD Deficiency
Patients with G6PD deficiency must strictly avoid fava beans (broad beans), as this is the only food with conclusive clinical evidence linking it to severe hemolytic crisis. 1
Primary Dietary Restrictions
Fava Beans and Related Legumes (Highest Risk)
- Fava beans (broad beans) are the most dangerous food trigger, causing severe oxidative hemolysis within 24-72 hours of consumption 2, 1, 3
- Falafel (often made from fava beans) is a significant trigger, accounting for 19.4% of diet-induced hemolytic crises 2
- Vetch (Vicia sativa) contains even higher concentrations of vicine (0.731%) and convicine (0.081%) than fava beans, making it a potent hemolysis trigger 4
- Chickpeas triggered hemolysis in 10.8% of cases in one large study 2
- Green peas caused hemolysis in 4.4% of cases 2
- Lentils were responsible for 2.8% of diet-induced hemolytic episodes 2
- Black-eyed peas accounted for 2% of cases 2
- Peanuts triggered hemolysis in 3.8% of patients 2
Emerging Evidence for Other Foods
- Blueberries have been reported to cause hemolysis in at least one documented case, with symptoms appearing approximately 12 hours after consumption 5
- The mechanism behind blueberry-induced hemolysis requires further research, but patients should be counseled to avoid this fruit as a precautionary measure 5
Clinical Context and Timing
The hemolytic crisis typically develops 24-72 hours after exposure to trigger foods (mean: 36±17.73 hours), presenting with the classic triad of 2:
- Pallor (100% of cases)
- Dark red/orange urine (89.6% of cases)
- Jaundice (87.8% of cases)
Dietary triggers account for 83.4% of all hemolytic crises in G6PD deficiency, making food avoidance the most critical preventive measure 2. This far exceeds infections (12.4%) and medications (4.2%) as precipitating factors 2.
Important Caveats
Food Additives
Food additives at their permitted levels in North America can be consumed safely by most G6PD deficient patients 1. The historical concern about food additives appears to be largely speculative and not supported by clinical evidence 1.
Regional Considerations
In agricultural regions where vetch production is high (approximately one million tons per year in some countries), patients must be specifically counseled about this risk, as vetch seeds may be consumed fresh and contain higher concentrations of hemolytic compounds than fava beans 4.
Methemoglobinemia Risk
Fava bean ingestion can rarely cause both acute hemolysis and methemoglobinemia simultaneously in G6PD deficient patients 3. Critically, these patients must never receive methylene blue treatment, as it will worsen hemolysis 3.
Practical Counseling Points
- Patients should receive lifelong dietary counseling emphasizing complete avoidance of fava beans and related legumes 5
- Parents of affected children should be educated that the peak age for hemolytic crisis is 1-3 years (92% of cases), with mean first presentation at 22.8 months 2
- Neonatal screening programs are recommended to identify G6PD deficiency before the first hemolytic episode occurs 2
- All processed foods should be checked for fava bean derivatives, particularly in Mediterranean and Middle Eastern cuisines where fava beans are common ingredients 2