well as a chef, I see this a lot. Many of the people who are displaying these allergies and sensitivities are not genetically predisposed to digesting these foods. Celiac's disease used to be only a first world disease, It didn't exist in any of the emerging or third world countries as, they started to get exposed to Western diets and exported wheat, they started to develop gluten allergies. The same thing is happening here with soy and corn. Europeans weren't designed to eat corn or soy. Most Asians don't get soy allergies and most Native Americans don't get corn allergies. As for peanut allergies because of cross breeding for better yield, disease and insect resistance we developed strains that when consumed by some folks it can be fatal. The original wild strains of peanuts actually can be consumed by people with peanut allergies because they naturally lack the allergen.
We in the west subsidize our farmers to grow and over abundance of foodstuffs more than we really can ever use. To justify this we add these ingredients to processed foods as flavoring agents, bulk filler, stabilizers and a myriad of other things, that you would never know was made from wheat, corn, soy and so on and so forth. We put it in everything (why do you need high fructose corn syrup in tomato sauce, bread or pasta?) because we gotta put it somewhere and its cheap, filling and highly addictive. All of these things are the perfect firestorm for allergies, intolerance and disease. We feed antibiotics and steroids to livestock because, we feed cattle corn and other grains. We do this because it's cheap, the problem is cattle did not evolve to eat corn or grain they are grazers, they eat grass. Grass fed cattle are healthier for you , they are low in cholesterol, high in omega3 and beta carotene and studies show you are less likely to develop coronary artery disease from eating it. Eating grain fed beef, you are more likely to develop, high blood pressure, heart disease, obesity, insulin resistance, high cholesterol and dozen other things including hormonal imbalances and antibiotic resistance. ( you don't hear about those reports to often, can't mess with big business).
The other contributing factor to the allergen problem is we are to clean as a society. The development of an efficient sewer system and sanitation system has doomed the western world to allergies. We no longer have a natural resistance to allergens and infections because, we are no longer exposed to these things on a regular basis as our ancestors were. A little bit of crap in the water makes you healthier , too much and Montezuma's revenge. I told my sister when here first Son was born to let him play in the dirt and stick things in his mouth (within reason and he will stay healthy. She put him in a sterile environment and he was sick all the time. The second kid, she followed my advice and he hasn't been sick yet. He is much more robust and filled with vigor than his old brother with the sniffles. Why is it the people who are always sick are the ones with the bottle of hand sanitizer? Ask yourself that question.
My rant is now over and I'm sure it made no sense and I may have wandered off topic. This whole thing is a quick fix. Eat better and roll around in the dirt . Drink a little crap in your water and you'll be fine.