Food intolerance is becoming much more of a household phrase these days. For those who haven’t thought about it much or never had a reason to look into it, this is a basic guide to what it is, what some of the most common intolerances are, and some other related information.

Food intolerances can come from a variety of sources. For example, some people can’t tolerate citrus fruits or other acidic foods. The food intolerances that trouble most people are chemicals (such as aspartame or preservatives), natural compounds (like caffeine), wheat and gluten, and, of course, lactose.

Sometimes it’s hard to distinguish a food intolerance from a food allergy. Their symptoms can be quite similar, but actually they are completely different bodily responses. A food intolerance is a digestive system problem.

If you have a food intolerance, you might experience headaches, gastrointestinal problems, or weight gain. (Wine, cheese and chocolate are notorious headache causers.) Gastrointestinal issues can include gas, bloating, constipation, or diarrhea, which are sometimes mistaken for Irritable Bowel Syndrome. You might also have allergy-like symptoms such as a runny nose, hives, or difficulty breathing.

Lactose intolerance is one of the most common things people suffer from. It is caused by a shortage of the lactase enzyme. Instead of digesting lactose normally, people with too little lactase can’t process milk sugars properly. When they consume dairy products, the result is fatigue, nausea, and a host of other digestive problems such as gas and bloating.

How serious is lactose intolerance? Children younger than two are especially susceptible to it. These children often need a special non-dairy formula to ensure proper nutrition. Most adults with lactose intolerance (5% of all adults in Ireland and the UK) can tolerate a tiny amount of dairy in their diets. Others can tolerate none at all.

Though more rare, foods that contain artificial preservatives, sweeteners, flavor enhancers, and colors sometimes trigger painful symptoms in people with an intolerance to such substances.

Another very common intolerance is wheat or gluten intolerance. (Gluten is a protein found in wheat.) These conditions have gotten a lot of press lately, and for good reason: gluten intolerance, also called celiac disease in its most serious form, has been linked to behavioral problems, weight gain, and even autism.

Celiac disease is an incurable condition that causes the immune system to attack a person’s own body. In this case, the autoimmune response is triggered by eating foods that contain gluten. Celiac disease can cause all of the symptoms of food intolerance, plus stunted growth and skin conditions. Left unchecked, it can eventually cause bone disease, anemia, and even cancer.

Unfortunately, gluten is found in all wheat products, and even in some products made from barley, rye, and oats. That means that people with gluten intolerance need to avoid certain alcohols, like beer. Wheat can also be found in unexpected places. It’s often used as a filler in ground meat and sausage.

There are many gluten-free and wheat-free breads, pastas, and cereals – but they’re not created equal. Just because a product is gluten-free doesn’t necessarily mean it’s safe for people with wheat intolerance. Gluten-free products can contain other wheat substances. Likewise, wheat-free products might contain barley, rye, or oats.

Basically, people who suffer from a gluten intolerance must become very good label readers!

If you suspect wheat, gluten, or any other intolerance, speak with your doctor as soon as you can. They will make a firm diagnosis and give you dietary guidelines to follow.

There is a great food intolerance test on the market that I would recommend to anyone who thinks they may be affected by one or several food products. It takes the guesswork out of figuring out what is causing the problem.

If you find out you do have an intolerance, seek nutrition guidance, as when patients attempt to cut out the offending food group, it can cause malnourishment. For example, some people avoid dairy products altogether because of their lactose intolerance. Without a good substitute, they risk calcium deficiency.

Sometimes our bodies cannot tolerate the foods we eat. This is known as food intolerance. When people consume foods that they’re sensitive to, such as dairy products for lactose intolerant individuals, their bodies have a negative physical reaction. The effects show up every time the food is consumed. If large quantities of the food are ingested, symptoms can be severe.

Food intolerance is sometimes mistaken for food allergies. But food allergies cause the person’s immune system to sit up and take notice. Food intolerance doesn’t involve the immune system. Neither is it linked to contaminated or spoiled foods; those cause food poisoning, not intolerance.

Additionally, food intolerance describes only the adverse physical reaction to the ingestion of certain foods. It does not address psychological reactions to food.

The Causes of Food Intolerance

Food intolerance is caused by the inability to digest certain types of food, usually due to insufficient amounts of the chemicals or enzymes needed to digest a particular food.

Lactose intolerance is very common. People who suffer from this condition don’t have enough of the enzyme called ‘lactase’. Therefore, their bodies can’t break down the lactose, or milk sugar, in dairy products.

Common symptoms of lactose intolerance include intestinal distress, gas, bloating, and bowel irregularities.

Other people can’t process alcohol because they don’t have enough of the enzyme ‘alcohol dehydrogenase’. They can become ill if they consume even a single alcoholic beverage.

The additives, flavor enhancers, and preservatives in processed foods are another common source of food intolerance. MSGs, caffeine, benzoates, and aspartame cause pain and fatigue in sensitive individuals.

Sometimes enzyme deficiencies can cause toxins to build in the system. Enzyme deficiencies can also stimulate the production of histamines. The human body normally produces histamines in response to allergens. In such cases, food intolerance can masquerade as an allergic reaction.

Who Suffers from Food Intolerance?

If your parents have food intolerances, chances are good that you’ll have them too. Ethnicity plays a role, too. Only 10% of northern and western Europeans suffer from lactose intolerance. Persons of Asian, African, Greek, and Native American descent are much more susceptible; lactose intolerance affects 70-90% of their population.

Newborns tend to produce more lactase, so they can digest lactose easier than adults and older children. The symptoms of lactose intolerance can appear in children as young as two, but many people develop it later in life. Gastroenteritis sometimes causes a dip in lactase levels, bringing on a temporary intolerance to dairy products. Children face a high risk of lactose intolerance following gastroenteritis. Half of all Asians are affected by alcohol intolerance.

What are the Symptoms of Food Intolerance?

The symptoms of food intolerance center on the digestive system. Sufferers may experience stomach pain, bloating, nausea, or loose stools. These symptoms are seldom life-threatening, but they can make a person miserable. They can manifest anywhere from a few hours to a few days after the food is consumed.

Food intolerance symptoms can become quite severe if a large quantity of the food has been consumed. People with a slight enzyme deficiency typically don’t experience symptoms as acutely as people with a larger deficit. Alcohol intolerance causes redness of the face, nausea, irregular heartbeat, headaches, and dizziness.

How is a Diagnosis Made?

Trial and error is the simplest way to test for food intolerance. This is done by removing one food from the diet for a while and monitoring symptoms for improvement. If symptoms decrease, the food is then reintroduced. A return of symptoms will reveal whether or not that food was the culprit.

Further tests are used to diagnose lactose intolerance. For example, your physician might recommend a test to measure the amount of hydrogen in your breath; a stool acidity test; or a blood glucose test to determine how well the patient digests milk sugar.

How is Food Intolerance Treated?

Food intolerance is usually controlled by removing the troublesome food from the person’s diet. For instance, lactose intolerant individuals can replace regular milk with soy milk.

If the intolerance is mild to moderate, the affected person can try eating only very limited amounts of the food in question. Mild lactose intolerance can be managed through the use of lactase enzyme supplements.

If foods are removed from one’s diet, they should be replaced with nutritious alternatives. It’s crucial to avoid malnutrition, especially in growing children. If you have questions about suitable food replacements, speak with your nutrition specialist.

The only real way to find out what intolerance you may have is to take a food intolerance test.