Why Am I Allergic to Everything I Eat?

Everything on the menu is a problem. You react to medications and supplements, even ones an expert prescribed, and your list of safe foods keeps getting shorter. This is a growing problem. The good news: you might be able to eat a lot of what you react to right now just by changing how you prepare it.

Why am I allergic to everything I eat?

Because your immune system has started treating ordinary food as a threat, and once that starts, the list tends to grow. It rarely stops at food: the same people react to medications and supplements, even when an expert prescribed them.

Clinicians have a name for much of this picture: mast cell activation syndrome, or MCAS. A 2020 review by an international group of clinicians notes that recognition of MCAS has grown significantly in the last decade, that it may affect up to 17 percent of the general population, and that most patients, however long they have been ill, can eventually find a treatment that gives them sustained improvement.^[1]

That matches what I see. I have helped thousands of people get into remission from this situation. The first thing I tell every one of them is that you may not need to cut a food out forever. Very often the problem is not the food. It is how the food meets your body, and that is something you can change in your own kitchen. It is also the work we do together inside Gut Brain Synchrony.

Why am I becoming allergic to more foods?

Your immune system evolved to fight parasitic worms, and sometimes it accidentally goes after a food protein that has a similar structure.

This is not a metaphor. Researchers at the European Bioinformatics Institute and Cambridge compared 2,712 known allergy-triggering proteins against proteins from parasitic worms and arthropods. They found 2,445 parasite proteins with significant similarity in sequence and structure to allergens. They even found a worm version of the most common pollen allergen, a target of IgE in people infected with schistosomes. In their words, allergy is the price of immunity.^[2]

A bored immune system: the old friends hypothesis

Your immune system is basically bored, because these parasites are not as common as they once were. This is called the old friends hypothesis. Rook and colleagues name the loss of helminth infections, less microbial diversity, diet and antibiotics as the modern changes behind large increases in allergies, autoimmunity and inflammatory bowel disease in high-income countries.^[3]

In his 2023 review, Rook describes the result as a broad failure of the mechanisms that should stop the immune system from attacking harmless allergens, and traces it to too little exposure to the organisms that drive its regulatory arm, organisms that come from our mothers, our families and the natural world, animals included.^[4] We live in a world much cleaner than our ancestors did. When the immune system does not have enough to do, it gets harmfully creative.

Histamine reactions to food

Much of the flushing, itch, bloating and headache after a meal is histamine. Mast cells release it when the immune system decides something is a threat, and food itself carries it.

Your gut is where histamine is supposed to be dealt with. Schnedl and Enko describe histamine intolerance as a disorder that originates in the gut: an enzyme in the gut lining, diamine oxidase, normally breaks down histamine from food, and problems in the gut lining, and some medications, reduce its activity. When it falls behind, histamine builds up and causes symptoms in the gut and well beyond it.^[5]

So there are two levers. One is the shape of the food protein your immune system meets. The other is how much histamine reaches your gut, and how well your gut clears it. Every one of the four methods below works on one or both.

Does cooking reduce allergens?

It can, and it is the first method: cook it fresh and eat it fresh. Your immune system reacts to the shape of a food protein, and heat changes that shape, so your body can read the cooked version as a different food.

Allergists at Mount Sinai built on exactly this. High heat largely destroys conformational epitopes, the parts of a protein defined by its folded shape. They challenged 100 children with milk allergy using extensively heated milk baked into foods. Sixty-eight tolerated the baked milk while still reacting to plain milk, and nine tolerated both. In all, 75 percent of the children tolerated heated milk. After three months of eating it, their skin-test reactions had shrunk.^[6]

The same team tested egg. Of 117 children with egg allergy, 64 tolerated egg baked into a muffin and a waffle. Those who kept eating it showed smaller skin tests and immune changes that paralleled the changes seen as children develop tolerance to regular egg.^[7]

Why fresh matters as much as cooked

Food that sits keeps changing. Bacteria convert the amino acid histidine into histamine, and they keep doing it in the container. In an FDA study, tuna salad seeded with a histamine-producing bacterium passed 500 ppm of histamine after two days at 30°C (86°F) and four days at 25°C (77°F), and the authors concluded it had to be held at 4°C (39°F) or colder to stop it.^[8] The longer food sits, the more histamine it can carry. That is the second half of the method: cook it, eat it, and make the next meal new.

Is walking after eating good for digestion?

Yes, and it is the second method: rub your stomach and go for a short walk after eating. This improves gastric motility and reduces the production of histamine.

Gastric motility is the churning that moves food on; food that lingers ferments. A meta-analysis of 20 studies on exercise and stomach emptying found that walking was associated with faster gastric emptying, and that gentle effort sped emptying while hard effort slowed it.^[9] That is why I say a short walk, not a workout.

Rubbing the belly works in the same direction. In a randomized trial in 80 hospital patients fed through a stomach tube, abdominal massage brought the rate of food left sitting in the stomach down from 30 percent of patients to 2.5 percent, and abdominal distension from 20 percent to 2.5 percent.^[10]

Chinese medicine has always paired the two. Slow clockwise circles around the navel after a meal, then a hundred unhurried steps, is old household advice for helping the Stomach send food downward instead of letting it stagnate.

Ginger and histamine: why warming herbs help

The third method is to prepare the food with warming herbs. Nothing exotic. This is stuff you have probably already got at home: onions, garlic, ginger, rosemary, oregano, sage, basically anything from the spice aisle. These plants aid digestion, feed the bacteria you need to break down histamine, and help you secrete more bile.

In Chinese medicine the Spleen and Stomach are the fire under the cooking pot. They like warmth and are injured by cold. Pungent, warm plants “warm the middle” and get stuck food moving, which is why fresh ginger has been a digestive herb for two thousand years. Here is what the research adds.

Is digestion stronger in the morning?

Chinese medicine says yes, and it is the fourth method: eat it earlier in the day. Your digestion is strongest in the morning, so food that sits badly at 9 p.m. might go down just fine at 9 a.m.

The classical body clock gives each organ a two-hour peak, and the Stomach’s runs from 7 to 9 in the morning, followed by the Spleen from 9 to 11. Breakfast and an early lunch fall in the hours when the digestive fire burns hottest.

Modern measurements line up. When 16 healthy men had their stomach emptying measured after meals at 8 a.m. and at 8 p.m., solid food took 53.6 percent longer to empty in the evening.^[16] In a randomized crossover study of 16 men, the energy the body spends processing a meal was 2.5 times higher after breakfast than after the same calories at dinner, and the rise in blood sugar and insulin was smaller in the morning.^[17] I go deeper into meal timing in Is It Better to Eat Earlier in the Day?

How to eat foods you react to again

If MCAS is part of a bigger picture for you, Lyme Disease: Start Here is a good next read.

Allergic to everything: your questions

Why am I allergic to everything all of a sudden?

An immune system without its old work starts picking new targets, and once mast cells are primed, reactions can spread from one food to many. The pattern can turn around.

Why am I sensitive to everything?

Usually because histamine is building faster than your gut can clear it. Food that sits, a slow gut and late heavy meals add to the load. Fresh food, a walk, warming herbs and earlier meals take from it.

Can you be intolerant to all food?

It can feel that way. Before you give a food up, try it cooked fresh, spiced well and eaten in the morning.

Your immune system needs a job, not a smaller plate.

— Brehan Crawford, L.Ac.

References

1. Afrin LB, Ackerley MB, Bluestein LS, et al. Diagnosis of mast cell activation syndrome: a global “consensus-2”. Diagnosis (Berl). 2020;8(2):137-152. doi:10.1515/dx-2020-0005
2. Tyagi N, Farnell EJ, Fitzsimmons CM, et al. Comparisons of allergenic and metazoan parasite proteins: allergy the price of immunity. PLoS Comput Biol. 2015;11(10):e1004546. doi:10.1371/journal.pcbi.1004546
3. Rook GAW, Raison CL, Lowry CA. Microbiota, immunoregulatory old friends and psychiatric disorders. Adv Exp Med Biol. 2014;817:319-356. doi:10.1007/978-1-4939-0897-4_15
4. Rook GAW. The old friends hypothesis: evolution, immunoregulation and essential microbial inputs. Front Allergy. 2023;4:1220481. doi:10.3389/falgy.2023.1220481
5. Schnedl WJ, Enko D. Histamine intolerance originates in the gut. Nutrients. 2021;13(4):1262. doi:10.3390/nu13041262
6. Nowak-Wegrzyn A, Bloom KA, Sicherer SH, et al. Tolerance to extensively heated milk in children with cow’s milk allergy. J Allergy Clin Immunol. 2008;122(2):342-347. doi:10.1016/j.jaci.2008.05.043
7. Lemon-Mulé H, Sampson HA, Sicherer SH, Shreffler WG, Noone S, Nowak-Wegrzyn A. Immunologic changes in children with egg allergy ingesting extensively heated egg. J Allergy Clin Immunol. 2008;122(5):977-983. doi:10.1016/j.jaci.2008.09.007
8. McCarthy S, Bjornsdottir-Butler K, Benner R. Storage time and temperature effects on histamine production in tuna salad preparations. J Food Prot. 2015;78(7):1343-1349. doi:10.4315/0362-028X.JFP-14-523
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10. Uysal N, Eşer İ, Akpinar H. The effect of abdominal massage on gastric residual volume: a randomized controlled trial. Gastroenterol Nurs. 2012;35(2):117-123. doi:10.1097/SGA.0b013e31824c235a
11. Wu KL, Rayner CK, Chuah SK, et al. Effects of ginger on gastric emptying and motility in healthy humans. Eur J Gastroenterol Hepatol. 2008;20(5):436-440. doi:10.1097/MEG.0b013e3282f4b224
12. Kempuraj D, Madhappan B, Christodoulou S, et al. Flavonols inhibit proinflammatory mediator release, intracellular calcium ion levels and protein kinase C theta phosphorylation in human mast cells. Br J Pharmacol. 2005;145(7):934-944. doi:10.1038/sj.bjp.0706246
13. Lu QY, Rasmussen AM, Yang J, et al. Mixed spices at culinary doses have prebiotic effects in healthy adults: a pilot study. Nutrients. 2019;11(6):1425. doi:10.3390/nu11061425
14. Domingos-Lopes MFP, Stanton C, Ross RP, Silva CCG. Histamine and cholesterol lowering abilities of lactic acid bacteria isolated from artisanal Pico cheese. J Appl Microbiol. 2020;129(6):1428-1440. doi:10.1111/jam.14733
15. Platel K, Rao A, Saraswathi G, Srinivasan K. Digestive stimulant action of three Indian spice mixes in experimental rats. Nahrung. 2002;46(6):394-398. doi:10.1002/1521-3803(20021101)46:6<394::AID-FOOD394>3.0.CO;2-D
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17. Richter J, Herzog N, Janka S, Baumann T, Kistenmacher A, Oltmanns KM. Twice as high diet-induced thermogenesis after breakfast vs dinner on high-calorie as well as low-calorie meals. J Clin Endocrinol Metab. 2020;105(3):dgz311. doi:10.1210/clinem/dgz311