Ask the Guru
Antihistamines And Bodybuilding
Question: I have three of your books and find them very informative. I have a question you don’t address in your books. Does taking Benadryl (diphenhydramine) negatively affect either muscle building or fat loss?
Answer: Regular antihistamine use can negatively affect calorie partitioning (where calories “go” when you eat them), yes. It’s not something I’ve looked into in great detail at this point, but the histamine system is involved in body weight regulation, and antagonizing it all the time seems to do very negative things in terms of both body weight and body composition.
Of some interest, I know a lot of people who find that lowered carb diets (especially full-blown ketogenic diets) allow them to avoid allergy medicine in the first place. Ketogenic diets tend to decrease immune system function a bit, and allergies are basically an overactive immune response.
By the same token, when people get sick on keto diets, they often take forever to get over it. So, by lowering carbs and essentially decreasing immune system function, you may not need to take the Benadryl in the first place. On that note, taking high doses of fish oils also modulates immune system and will probably help with this.