Tomato is a nightshade plant. So, those allergic to tomatoes may also exhibit an allergy to other members of the nightshade family such as potatoes, peppers, and aubergines.
Tomatoes, considered to be one of the healthiest foods, unfortunately, cannot be tolerated by a few. This is because they suffer from a tomato allergy that prevents them from consuming this vegetable even in small amounts. Specific proteins known as profilins, present in tomatoes, are found to be the main culprits in triggering the allergic reaction.
It is observed that tomato allergy differs from person to person. For instance, one may be allergic to raw tomatoes but may not experience any adverse effects on consuming ketchup, sauce, and soups that contain the offending food. In some cases, the reaction occurs after a few minutes or maybe hours after ingesting the tomatoes. While others experience the symptoms 2 to 3 days after consuming the allergic food. So the onset, severity, and duration of symptoms experienced will vary in each individual.
An allergic response to foods that one is allergic to leads to the release of histamines―chemicals in the body that trigger a wide range of allergy symptoms. Some of these are discussed below.
When tomatoes are consumed, exposure to allergic components in them triggers an abnormal response, leading to the production of histamines. When these chemicals pass through the gastrointestinal tract, they cause abdominal pain and indigestion. Histamines can also mess with your bowel movement and cause diarrhea. They tend to reduce the bowel transit time, which results in excretion of loose, watery stools.
People suffering from tomato allergy may also develop skin problems like eczema and hives shortly after consuming them. The release of histamines into the skin causes irritation, inflammation, and itching. In some cases, even simply touching the tomatoes can also cause a rash, swelling, redness, and itching in the exposed areas of the skin. Depending upon the severity of the allergic reaction, these skin problems may be localized or widespread.
Frequent sneezing, watery eyes, getting a runny nose and a cough after eating tomatoes are also recognizable symptoms of tomato allergy. Histamines released into the body prompts the blood vessels to dilate as well as increase vascular permeability. As a result, there is gradual fluid loss from various tissues and small blood vessels, particularly those located in the nose. This fluid leakage from blood vessels is what causes runny nose and watery eyes in people affected with tomato allergy.
In extremely rare cases, some allergic individuals may suffer from a fatal allergic reaction, anaphylaxis, in which the symptoms worsen rapidly, almost seconds after consuming tomatoes. This severe form of allergic reaction affects the whole body. Difficulty in breathing, tightness in the throat, swelling of the face, lips, and tongue are some of the most common symptoms of this catastrophic allergic reaction.
A blood test is one of the most reliable methods to detect tomato allergy. It is observed that the body releases Immunoglobulin E (IgE) antibody after exposure to allergens. The blood test involves drawing a sample of blood and then checking for the presence of IgE. If the test is positive, it indicates that the person is allergic to the food.
A patch test can also reveal whether you are allergic to tomatoes. In this test, the patch is smeared with the offending food and then attached on the back for a day or two. In case the exposed areas of the skin develop a rash, it is an indication of tomato allergy.
In this test, a very small amount of allergic food is placed on the skin. A sterile needle is then pricked through the suspected allergen into the skin. This allows the suspected allergen to enter the skin. In case the exposed area of the skin develops a bump or forms a rash, it is an indication of an allergy.
Eliminating tomatoes and tomato-based products from the diet is the best solution. When tomatoes are cooked, proteins present in them may get denatured, meaning the protein structure may change. This may help in preventing or reducing the symptoms of an allergic reaction. As far as treating the symptoms are concerned, one may take oral antihistamines that help counteract the effects of histamine. This works to relieve the symptoms effectively. Applying corticosteroid creams can also help to ease itching and skin inflammation.
Another way to manage tomato allergy is to boost immunity. Eating foods high in antioxidants, vitamin B complex, and Quercetin (a flavonoid) strengthens the immune system. One can also take these nutrients in a supplemental form to reap their benefits. Improved immunity may help block the effects of histamine, in turn contributing to alleviate and even prevent the symptoms of tomato allergy.