What is the difference between food allergy and food intolerance?
Food allergy is an immune system reaction that occurs soon after eating a certain food. Even a tiny amount of the allergy-causing food can trigger signs and symptoms such as digestive problems, hives or swollen airways. In some people, a food allergy can cause severe symptoms or even a life-threatening reaction known as anaphylaxis.
Food allergy affects an estimated 6 to 8 percent of children under age 3 and up to 3 percent of adults. While there's no cure, some children outgrow their food allergy as they get older.
It's easy to confuse a food allergy with a much more common reaction known as food intolerance. While bothersome, food intolerance is a less serious condition that does not involve the immune system.For example, being allergic to milk is different from not being able to digest it properly because of lactose intolerance.
How food allergies works?
When you have a food allergy, your immune system mistakenly identifies a specific food or a substance in food as something harmful. In respose, your immune system triggers cells to release an antibody known as immunoglobulin E (IgE) to neutralize the allergy-causing food or food substance (the allergen).
The next time you eat even the smallest amount of that food, IgE antibodies sense it and signal your immune system to release a chemical called histamine, as well as other chemicals, into your bloodstream. These chemicals cause allergy symptoms.Adults and children tend to have different allergens
In adults, the majority of food allergies are triggered by certain proteins in:
Shellfish, such as shrimp, lobster and crab，PeanutsTree nuts, such as walnuts and pecans，Fish
In children, food allergies are commonly triggered by proteins in:Peanuts，Tree nuts，Eggs，Cow's milk，Wheat，Soy .
Who is at risk?
Family history – scientists believe that some food allergies could be caused by genes people inherit from their parents. For instance, people who have a parent or sibling with a peanut allergy have a 7 times higher risk of having that allergy themselves compared with those with no family history.
Other allergies – those who have asthma or atopic dermatitis have a considerably higher risk of developing a food allergy than people with no other allergies.
Early years – research has also shown that babies born by cesarean section, who were given antibiotics at birth or within the first year of life, and those who had food introduced late, after 7 months, all had higher risks of allergies.
Gut bacteria – recent research shows that the gut bacteria in adults with nut and seasonal allergies is altered. Specifically, they have higher levels of bacteroidales and lower levels of Clostridiales strains. Scientists are trying to determine if influencing gut bacteria could help treat or prevent allergies.
How to deal with the food allergies?
The primary way to manage a food allergy is to avoid consuming the food that causes you problems. Carefully check ingredient labels of food products, and learn whether what you need to avoid is known by other names.
Avoiding an allergen is easier said than done. While labeling has helped make this process a bit easier, some foods are so common that avoiding them is daunting. A dietitian or a nutritionist may be able to help. These food experts will offer tips for avoiding the foods that trigger your allergies and will ensure that even if you exclude certain foods from your diet, you still will be getting all the nutrients you need. Special cookbooks and support groups, either in person or online, for patients with specific allergies can also provide useful information.
Many people with food allergies wonder whether their condition is permanent. There is no definitive answer. Allergies to milk, eggs, wheat and soy may disappear over time, while allergies to peanuts, tree nuts, fish and shellfish tend to be lifelong.
There is more than one type of allergy, of course, but there are also trigger allergies. If you want to know about trigger allergies, please click here.