The major threat the gm foods pose to human health is:

These are the major threats to human health caused by GM foods.
1. Food allergy- allergy occurs when normally harmless proteins enters the body. Structures of these proteins could possibly altered by the process than can result in an immune response.

2. Increased toxicity- insertion of exotic genes to a possible food is a concern. That production of toxins by these exotic genes can be altered resulting into a threat to health

3. Decreased nutitional value- Theoretically, GM foods have lower nutritional vale than the traditional food.

Others could be increased susceptibility to infection due to bacterial resistance, imbalance nutrition and others.