Today I’d like to explore food allergies vs. intolerance vs. sensitivity. I think there is a lot of confusion around these terms and how, even if, they differ. The words are bandied about the news and Internet, along with fear-inducing warnings and questionable information. It seems more and more people have problems with certain foods, or claim they do, and it’s hard to know when the claims are serious. You may have been on an airplane where they announced “No peanuts today as there is a passenger with a peanut allergy on board.” Or maybe your child’s school sent a note prohibiting peanut-containing snacks or lunches. “Wow,” you may think, “is it really that dangerous?” For some people the answer is yes. So let’s outline the differences and similarities.

          An actual allergy to a food causes the body’s immune system to react, sometimes aggressively. The body views a protein in the food as an invader and attacks the invader with antibodies. You may be familiar with people taking an anti-histamine medicine when they have hives or itchy seasonal allergy symptoms – the histamine produced by the body in this fight against invaders causes those symptoms. However, a true food allergy can be much more serious, causing anaphylactic shock in some people. Other symptoms are less serious but can increase in severity if exposure continues. These could be skin reactions, like hives, swelling, and itching or digestive symptoms like vomiting, diarrhea, nausea, and stomach pain.

          A food intolerance does not involve the immune system. Intolerance most often means your body cannot break the food down properly in your digestive track. Milk intolerance is the most common, and is due to lack of the enzyme lactase needed to break down the lactose in the milk. Other causes of intolerance are certain food additives like sulfites or nitrites; extreme aversion to a certain food; and intolerance of naturally occurring substances like histamines. Generally the symptoms of food intolerance are gastrointestinal-related. Some blog articles point to skin disorders from intolerances but the medical sites did not list skin problems as related to food intolerance. Food intolerance will not cause anaphylactic shock.

          Food sensitivity is sometimes the term used for food intolerances, but where it is distinguished it refers more to the    discomfort some people may experience after eating spicy foods or acidic foods, or the faint mouth itchiness some people get after eating a banana but with no other symptoms. Food sensitivities also do not involve the immune system.

While allergies and intolerances share some symptoms, the main difference is the involvement of the immune system. Also, reactions from a food allergy generally begin immediately or within a short time of eating the food, where reaction from a food intolerance may not show up for hours or even a few days. An allergy causes a reaction from even a small amount of the food but intolerance usually flares up after eating a lot of the problem food. I am lactose intolerant but find I can have a small amount of cheese, for instance, without symptoms, especially if I indulge only on occasion. My experience highlights another difference – an allergy causes the reactions every time the offending food is eaten but a food intolerance often only flares up if the food is eaten often. Allergies can be life-threatening but intolerances are not.

Just as food allergies and intolerances can be outgrown or fade, we can also develop an allergy or intolerance as adults, even after eating the food for years without problems. This is very common for milk intolerance. Children with food allergies often outgrow them, especially milk, egg, and soy allergies, usually by age 6 or 10. It is less likely they will outgrow peanut, tree nut, or shellfish allergies.[1] The most common allergens, accounting for about 90% of food allergies, are: milk, eggs, fish, shellfish, peanuts, tree nuts, wheat, and soybeans. [Note that gluten is not listed here, even though it seems to be such a huge topic. You may think people with celiac disease(~ 1% of the US population) are allergic to gluten but it is not an allergy, rather it’s an autoimmune disease.  ‘Non-celiac gluten sensitivity’ is a fairly new disorder and one that is difficult to diagnose, as there is no test for it and removing gluten from the diet may also remove other causes of the symptoms.]

If you suspect you have an allergy to a food, you should avoid the food and seek testing to be sure. If it proves you are allergic you will need to continue to avoid the food, and other foods that may include it. If your symptoms are severe you should carry an epinephrine pen at all times.  If you suspect you have a food intolerance, the best way to be sure is to track what you’ve eaten when you experience the symptoms, and then try an elimination diet on the most likely culprits. This should tell you if you can eat a little on occasion or should just eliminate it for good. Remember to check on preparation when eating out – was the sauce made with shrimp stock and you are allergic to shrimp? I have a friend who is allergic to potatoes and has to be careful of fried foods, soups, breads, and sauces because they often have potato or potato starch, or were cooked alongside potatoes. Read labels, ask questions, and protect your health.

[1] http://blog.foodallergy.org/2013/09/13/who-is-likely-to-outgrow-a-food-allergy/

 

20150131_glutenGluten-Free! shouts from a lot of packages in the grocery. “Paleo” is no longer an era but a dietary theory. Books carry titles like Wheat Belly and Grain Brain. Most restaurants now feature gluten free dishes. “What’s all the fuss?” you ask. “People have been eating grains for centuries – why all the hoopla now?” Theories abound on the topic, but not a lot of science proves any of them. Much of the talk is hype, some is real.

Now, that’s not to say that celiac disease is not real, or that no one has gluten sensitivity. A little less than 1% of Americans have celiac disease, and less than one-half percent have a true gluten sensitivity that is not celiac disease. People who truly have a digestive disease or an allergy need to avoid all foods that irritate the condition.

But what about the rest of us? Should we really shun all wheat, or even all grains entirely?  Most of the medical and scientific people who are looking into this say no, a few say yes. Dr. David Perlmutter blames eating grains for diabetes, Alzheimer’s, obesity, and more. Other physicians and scientists debunk his theory with studies that contradict him.

So who is a non-medical, non-scientist supposed to believe? It really comes back to moderation. If you do not have celiac or gluten sensitivity – and you would know this painfully as soon as you consumed gluten – you should not be concerned about eating gluten containing foods, in moderation. Of course, I do not mean doughnuts, bagels, cookies, cakes made with highly refined white flour, stripped of nutrients and fiber. Even whole grain breads should be limited, especially if you aren’t a label reader (future post!), as some commercially made items are not as wholesome as the package indicates. Whole grain foods provide more nutrition and longer satisfaction for your stomach. Brown rice, bulghur wheat, quinoa, oats – delicious and good for you!

Here is a good article examining some of the claims of the avoid-gluten-at-all-costs crowd, and some arguments why those claims may not hold up: http://m.theatlantic.com/health/print/2013/12/this-is-your-brain-on-gluten/282550/