I think Koir had said this about your first essay, but a general rule to go by when writing an essay or paper is that you assume your reader knows nothing about your subject matter. That's why I added things like the full name of HACCIP and a brief definition of dyspnoea. If I hadn't been online to readily research these things, part of your meaning would have been lost to me. You want your readers to easily understand your subject matter.
Also, when using parentheses within parentheses, instead of using a second pair of (), use brackets []. I made this change with your citations to ("Food Allergies On The Rise...[Cover Story]").
The system to exclude alien substances from our bodies is called an immune response. It is called an allergy when this reaction exceeds the extent to which a body needs defended. When our bodies judge a food, which is not an alien substance, to be primarily a harmful thing, we become allergic to that food (Sodhi 66). Even now, Scientists cannot explain clearly why food allergies happen (“Food Allergies On The Rise…[Cover story]” 1). In the United States, there are 30,000 food allergy related emergency room visits and 200 related deaths every year (Sodhi 66). The substances which cause food allergies are called allergens and include milk, eggs, peanuts, tree nuts, fish, shellfish, soybeans, and wheat (“Food Allergies On The Rise…[Cover story]” 1). According to a study by Sodhi, “when both parents have allergies, there is 67% chance that the children will also have them” (66). Children’s food allergies have increased eighteen percent in the past ten years. The most terrible state of allergic reaction is called anaphylaxis. Instances of anaphylaxis increased by twenty-five percent during 1990 to 2000 in Minnesota, and there is data that the number was high for those under twenty years old. Anaphylaxis causes a problem of both dyspnoea (difficulty breathing) and shock. If it is not treated, the anaphylactic reaction becomes fatal. Many scientists are desperate to find out the cause of hyperesthesia (From what I can tell, hyperesthesia is a nerve and sensory condition that is unrelated to food allergies 
You might want to strike this reference to it.). It is necessary to know what kind of food could be an allergen and whether an allergic reaction needs to be avoided. Also, it is important for those with food allergies to carry epinephrine for self-management (“Food Allergies On The Rise…[Cover story]” 1).
Okay, almost done!