Many people in the Paleo crowd suspect that they have an adverse reaction to ingesting foods containing histamine, a naturally-occurring chemical found in some foods and in our bodies. However, despite these anecdotal claims, research tells another story, explains Anne Marie Irani, MD, professor emeritus of pediatrics at the Children’s Hospital of Richmond at VCU, and secretary general of the American Board of Medical Specialties. "There is no scientific data demonstrating significant differences in response to ingested histamine between different subjects," she says.
Of course, having an "adverse reaction" is a subjective term. So, why do so many people allegedly have issues with histamine? Ahead, Dr. Irani explains.
How does histamine affect the body?
Histamine is a chemical that's produced and stored in the mast cells in your body. When your body encounters what it perceives to be an allergen, a histamine response is rapidly triggered, resulting in a cascade of different symptoms, Dr. Irani says.
Is histamine intolerance a real thing?
This is a tricky question to answer. Anecdotally, many people say that they experience an adverse reaction to certain so-called "histamine foods." But there haven't been studies proving that histamine is actually the cause, Dr. Irani adds. (FYI, research on food intolerances is lacking in general.) The main theory behind histamine intolerance is that some people lack the proper enzymes needed to break down or process it, kind of like lactose intolerance. Again, this hasn't been 100% proven.
What are the symptoms of histamine intolerance?
Usually, histamine can trigger symptoms that we associate with seasonal allergies, such as sneezing, itching, hives and watery eyes. People who are believed to have histamine intolerance may also experience diarrhea, headache, asthma, flushed skin, wheezing, abdominal cramps, itching, and hives, Dr. Irani says. But here's the other thing about histamine: consuming large quantities of histamine can be toxic to everyone, regardless of their tolerance level. According to the American Academy of Allergy, Asthma & Immunology, histamine toxicity is a form of food poisoning caused by eating spoiled fish. Histamine toxicity is often confused for a fish allergy, because it results in the same sort of symptoms, such as flushing, nausea, burning in the mouth, and headache.
What are some high histamine foods?
We know that biogenic amines such as histamine increase when food ripens, ages, and spoils, Dr. Irani says. That's why "histamine is most often found in fermented foods," such as wine and cheese, she adds. Other examples of fermented foods include kimchi, pickles, and cured meats. It's hard to measure how much histamine a food contains, because amounts can vary depending on how long it ferments or even how it's stored. Some people also claim that certain foods can naturally be "histamine liberators," meaning they release histamine, such as avocados, citrus fruits, and eggplant. However, there's no scientific proof that this is the case, she adds. And others swear that egg whites and chocolate are histamine bombs and should be avoided.
How do you fix histamine intolerance?
Many "low-histamine diets" on the internet suggest that you should just steer clear of any food that you believe might have histamine in it. However, researchers say that you should "avoid generalized, restrictive, and long-term low-histamine diets that unnecessarily reduce patients' quality of life." Other studies suggest that taking an antihistamine before eating helps quell these sort of symptoms, too. But, if you know that a certain food makes you feel ill every time you consume it, that's a clear sign you should see an allergist or healthcare provider who can test for food allergens and diagnose you appropriately.
As the study author in a German study about histamine points out, the fact that so many people on the internet claim to have histamine intolerance might actually make more people believe that they, too, have it. In other words, just because someone posted about having a histamine intolerance or allergy doesn't necessarily mean you do, too.