Can formula actually cause allergies?

Yes. The cows' milk protein and the soy protein used in most formulas are foreign proteins. When babies are exposed to non-human milk, they actually develop antibodies to the foreign proteins. Research has shown that, without exception, the important food allergens found in milk and soybean formulas are stable to digestion in the stomach for as long as 60 minutes (as compared to human milk protein which is digested in the stomach within 15 minutes). The foreign proteins pass through the stomach and reach the intestines intact, where they gain access and can produce sensitization. While research in this area is still relatively new, this early exposure to foreign proteins may be the predisposing factor in such illnesses as eczema and asthma.