Updated: May 2019
#1 A low histamine diet will decrease total body histamine. This statement may be true for those suffering with dietary histamine intolerance. The theory of dietary histamine intolerance is that histamine is absorbed into the blood from food, especially if the diamine oxidase enzyme is not working well (DAO is an enzyme in the digestive system that breaks histamine down). However, if excess blood histamine is from a different source (e.g. seasonal allergies), a low histamine diet will not help. I have talked with many clients that assume they need to follow a low histamine diet because they have histamine-related symptoms. A low histamine diet may or may not help.
#2 Histamine releasing foods. Certain foods (e.g. egg white, strawberries, etc.) are listed as “histamine releasing foods.” When I completed my master’s thesis on this topic in the early 1990s, I could not find any research to support this theory. The theory was circulated and was eventually assumed to be fact. The “histamine releasing food” lists are based on foods that people have reported to be problematic – resulting in long lists and over restriction.
#3 Certain probiotics are better for histamine related symptoms. This statement is likely true, but there is not enough information to give a definitive answer. Some bacteria produce histidine decarboxylase (which creates histamine), and others produce diamine oxidase (which breaks histamine down). Therefore, some probiotic products are likely better than others for histamine-related symptoms, but more research is needed. Research is like a puzzle. If you have twenty pieces from a five-hundred-piece puzzle, it is difficult to determine the picture.
Similarly, if you only have a few studies, it is hard to answer research questions, like “what is the best probiotic for histamine related symptoms?”.
#4 The body will start making more histamine if you take antihistamine medications. The best approach is to improve your symptoms through lifestyle changes (diet, stress reduction, etc.), but in some cases, lifestyle changes are not enough. Unfortunately, many patients are fearful of medications, because of inaccurate statements on the internet. One of these rumors is that antihistamine medications cause the body to make more histamine. If you think about it objectively, it does not make sense. Certain antihistamines block H1 receptors (taken primarily for seasonal allergies, e.g. Claritin, Benadryl, etc.) and other antihistamines block H2 receptors (taken primarily for excess stomach acid, e.g. Tagamet, Zantac, Pepcid, etc.). If taking antihistamines caused the body to make more histamine, you would expect that a common side effect of H1 antihistamines would be increased stomach acid and H2 antihistamines would be allergy symptoms. However, these are not common side effects.
Additionally, antihistamine medications would stop working after awhile if they increased histamine. Some people report this, but the great majority do not. Once again, it is best to avoid medications if you can improve your symptoms through lifestyle changes, but it is unfortunate when people avoid medications that could improve their quality of life, because of internet misinformation.
#5 There is a “right” low histamine diet. Readers often ask, “Which low histamine diet on the internet is the best one?”. Unfortunately, there isn’t an answer. The low histamine diet is a guideline, not an exact science. Also, food tolerances vary between individuals. Therefore, there isn’t a “right” diet. The Problem with Diet Restriction Lists discusses this topic further.