What a great question and as over 12 million Americans have been diagnosed with a food allergy, millions more are estimated to be undiagnosed with allergies, and millions of countless others are estimated to be living with food sensitivities. Reactions to food are commonly grouped under a single allergen umbrella, yet there are major differences between the two main types.
ALLERGY VS. SENSITIVITY
Food Allergies are an immediate, immunologic response. Allergies may display as hives, swollen lips, or in the most serious cases, a potentially fatal anaphylactic reaction (http://www.foodallergy.org/section/a ). According to the Food Allergy and Anaphylactic Network, â€œeight foods account for 90% of all food-allergic reactions. They are milk, egg, peanut, tree nuts, fish, shellfish, wheat, and soy.â€ (http://www.foodallergy.org/section/common-food-allergens1 ).
Food Sensitivities is a physiologic reaction often resulting in the very symptoms you have mentioned, as well as headaches, upset stomach, bloating, and gas. Lactose intolerance or gluten intolerance (not Celiac Disease) would fit within this group. Each time someone with a food sensitivity eats the particular food their body is not tolerating, their digestive tract becomes inflamed.
MOST COMMON FOOD SENSITIVITIES.
Here are the most common foods known to cause allergic or sensitivity reactions:
â€¢ Wheat and gluten
â€¢ Peanuts and tree nuts (walnuts, almonds, cashews)
â€¢ Milk and dairy products (cheese, yogurt, ice cream)
â€¢ Corn and corn derivatives (found in 90% of processed food!)
â€¢ Soy and soy derivatives (cereals, processed vegetarian products, meal or snack bars)
â€¢ Nitrites and nitrates (processed meats)
â€¢ Active yeast (beer, baked goods, B-vitamin supplements)
â€¢ Sulfites (http://extoxnet.orst.edu/faqs/additive/sulf_tbl.htm) (wine, dried fruit, beer, canned seafood)
â€¢ Caffeine (need I say more?)
â€¢ Sugar substitutes (saccharin, acesulfame-K, phenylalanine, aspartame, sucralose)
â€¢ Sugar alcohols (sorbital, mannitol)
â€¢ Food colorings and dyes (http://www.cspinet.org/new/201006291.html) (red 40, yellow 5, yellow 6)
â€¢ Pesticides (designed to kill bugs and bacteria, makes sense that they will harm us as well (http://www.ccohs.ca/oshanswers/chemicals/pesticides/health_effects.html ))
Elimination diets are believed to be the gold standard for identifying the true cause of your food sensitivity, although the exact formula for that diet may differ per your case. Before beginning any diet as major as this one, I highly suggest you consult a registered dietitian (www.eatright.org) to ensure you are getting all of the nutrients you need. In a typical elimination diet, you may be asked to avoid many if not all of the most commonly reactive foods such as those listed above for anywhere from a few weeks to a few months depending on your case. The amount of food restrictions may differ depending on the level of severity your symptoms display. In your case, the symptoms mentioned are not as damaging as severe diarrhea and vomiting would be, therefore your elimination diet may be less restrictive than a person experiencing major gastrointestinal upset.
During the first several weeks as you follow a diet void of the foods most likely to be causing your symptoms, you will enjoy hypoallergenic foods. Allowed foods might include rice, quinoa, buckwheat, lamb, pears, apples, lentils, peas, and nearly any vegetable or bean. During this time you will hopefully begin to notice your symptoms subside, once this occurs it means the damaging food is no longer in your diet. After completing the major elimination phase, you will begin to slowly reintroduce the food you have eliminated one at a time until your symptoms reappear (usually within 48 hours after eating the reactive food). It is best to only introduce one food at one meal and then wait to see if your symptoms return. It is also advised that you wait one complete week before experimenting with the next food. This is the best way to identify the harmful food with certainty.
There are more simplistic versions of the elimination diet and as I mentioned each health professional may do things in their own way as well. The key of any type of elimination diet is to follow some form of a hypoallergenic diet until symptoms disappear before reintroducing any of the suspected reactionary foods.
For more complete details on the elimination diet or before making any drastic changes to your own diet, please consult your doctor or dietitian as you may put yourself at even greater risk due to nutrient deficiencies without their guidance.