According to multiple expert sources, up to one in 10 Americans or more have either an allergy, sensitivity, or intolerance to a food. About a third of these sufferers have an allergy that is potentially life-threatening. This calls for greater caution than ever among product manufacturers.

What distinguishes these three conditions? An allergy is a response by your body’s immune system: think hives, rashes, or in a worst-case scenario, anaphylaxis. A food intolerance happens when your body fails to digest a food or an ingredient in food. Lactose intolerance is probably the most common.

Over time, the body loses the ability to produce the enzyme (lactose) that digests the carbohydrate in dairy foods, causing bloating, gas, and sometimes diarrhea. Taking a lactase enzyme (Lactaid tablets) when you drink milk or eat dairy foods, will usually prevent symptoms of lactose intolerance. A food sensitivity, on the other hand, can produce symptoms that are unrelated to food allergies or intolerances. It’s not well-understood, but people can report stomach pain, joint pain, or even light-headedness.

Fermented foods are all the rage, and that’s not going away. Fermented foods aren’t exempt from causing allergic reactions, intolerances, or sensitivities though. Foods such as kimchi, kefir, sauerkraut, and wine, can help feed and grow a healthy gut environment. Yet approximately 10% of the US population reports hypersensitivity to wine. Many experts have singled out sulfites as responsible for the reported reactions to wine, which range from headaches to sinus problems to hives, flushing, and asthma-like symptoms.

Sulfites are known to cause sensitivities, yet results of the study, “Allergic and intolerance reactions to wine,” published in 2018 in Allergologie Select, revealed that other components in wine could also be culprits, at least for some people. These included the grape proteins; themselves, ingredients used in “fining” wines, such as fish gelatin, molds and yeasts; and even proteins from insects that contaminate the mash.

On the other hand, fermentation can also hold promise for reducing food sensitivity. A 2020 study published in the journal Nutrients looked at the changes in cashew allergenicity during the fermenting of cashew “cheese.” Five different cashew cheeses, including analogs of brie and bleu, were studied, and from start-to-finish, reductions in allergen content ranged from 29% to 66%.

Someone with a true allergy to cashews would still need to avoid this cheese, but these results suggest that those with milder sensitivities may have an option, especially if the fermentation process can advance to further reduce cashew allergen content. It should be noted, however, that the study did not take into consideration that the analogs used a starter different from the classic versions which contain fungi from the Penicillium genus, itself a potential allergen.

Monosodium Glutamate (MSG) Sensitivity

In 1969, a physician published a letter to the editor of a medical journal in which he noted symptoms of headache, flushing, and light-headedness after eating Chinese food. He didn’t know the reason, so he suggested several possibilities. Monosodium glutamate—MSG—used in cooking was the only one that stuck.

The news immediately went “viral” and soon MSG was the subject of widespread scrutiny and anecdotal derived condemnation. A number of product manufacturers and restaurants stopped using it, “No MSG” banners appeared on restaurant menus and food labels.

The conundrum is that in more than 50 years of research, MSG sensitivity has not been sufficiently validated. In fact, except for some few studies with children, it has been disproven in numerous large, randomized, double-blind controlled studies.

It’s difficult to connect the MSG-sensitivity dots: MSG is made up of two components, sodium and glutamate. Sodium is present in most foods, and is far more common than MSG in the diet. Glutamate is an amino acid, a building block of protein. It is a “non-essential” amino acid because the body already makes its own glutamate in far greater amounts than is derived from the diet, albeit bound to its proteins. Many common foods are natural sources of glutamate, including mushrooms, tomatoes, and certain cheeses, yet sensitivities to them are uncommon.

Glutamate is poorly absorbed into the bloodstream. About 95% stays in the digestive tract, so much so that it is the most prevalent amino acid in the gut. It also is important for many of the gut’s metabolic and immune functions.

In spite of the lack of definitive evidence for MSG being a potential allergen, consumer perception has power and many US manufacturers are hard-pressed to use MSG. Moreover, some food retailers, such as Whole Foods Markets, maintain a list of banned ingredients, a list that includes MSG.

While MSG still has some hurdles to overcome to regain widespread acceptance in the US, the recent surge in interest in umami is returning cachet to its original source: glutamate.

The Staff of Life—Without Gluten

Celiac disease is an autoimmune condition that affects about 1 in 100 persons. It doesn’t cause an immediate reaction, so it’s sometimes not considered a “true” allergy. However, if a person with celiac disease eats foods containing gluten, consequences can include the full gamut of gastric disturbances. Unaddressed, this can eventually lead to weight loss and malnutrition.

Avoiding gluten, found only in certain grains, including wheat, rye, barley, spelt, and bulgur, is the only sure solution. For manufacturers, the FDA sets a limit of below 20 ppm to qualify for a gluten-free label claim. However, some persons with severe forms of celiac disease cannot tolerate even that level. Many manufacturers of gluten-free products strive for levels as low as 5-10ppm.

In addition to celiac disease, there is “non-celiac gluten sensitivity”, or NCGS. About 80% of persons with irritable bowel syndrome (IBS) report that one or more gluten-containing foods trigger their symptoms.

Perhaps because of the abundance of “gluten-free” labels on packaging, gluten has unfairly been branded as an unhealthy component of food. Unless a person is gluten sensitive or has celiac disease however, avoiding gluten is not a strategy for improving health. If a grain contains gluten, it will do so whether it is in a whole or refined form. 

Oats don’t contain gluten but using them in a product intended for a gluten-free consumer can be tricky. Oats are often grown by farmers who also grow wheat or other gluten-containing grains. As much as they try to keep the other grains separated, some cross-contamination can happen. Unless the oats are certified gluten-free, it can be difficult to guarantee that a product is gluten free, even if the ingredients aren’t “supposed” to have any gluten.

Buckwheat, despite its name, has no gluten. It’s not even technically a grain, although its seeds are eaten and it can be milled into flour. (Botanically, it’s actually related to rhubarb.). Some ancient relatives of wheat, such as emmer and Khorosan (a.k.a. kamut), also have been shown to not trigger reactions in wheat-sensitive persons, although true celiacs should still avoid these grains.

Keith Ayoob is Associate Clinical Professor Emeritus of Pediatrics at the Albert Einstein College of Medicine, NYC and creator/director of Cut-to-the-Chase Nutrition, an information source dedicated to “busting myths, minimizing misinformation, and neutralizing the negatives” of nutrition. He also is editor of the Edible Rx newsletter. Dr. Ayoob may be contacted via www.cuttothechasenutrition.com.

Food Allergies by the Number$

Allergy-friendly food are experiencing a 27% CAGR. Nearly half of US adults—85 million — do not purchase foods containing one of the top nine allergens because they or someone in their household has a food allergy. Instead, they spend more than $19 billion per year on specialty foods free of allergens.— Food Allergy Research & Education organization (FARE)

New Kids on the Chopping Block

While sesame was added to this list of major allergens when Congress passed the Food Allergy Safety, Treatment, Education, and Research (FASTER) Act of 2021. It joined the eight other major allergens for which labeling is required. Approximately 1.6 million Americans have a sesame allergy. About five times as many consumers are allergic to coconut, which caused it to be lumped in with tree nuts as an allergen even though botanically coconut is a fruit.

Eight is not enough

While there are more than 160 foods known to cause food allergies, according to the FDA, over 90% of food allergies can be attributed to nine foods: milk, eggs, fish shellfish, tree nuts, peanuts, wheat, sesame, and soybean. Foods containing any of these nine allergens must state so on the food’s nutrition facts label. (The FDA added sesame in 2022 and since January 1, 2023, it is required to be labeled as an allergen on packaged foods and dietary supplements.)

Legal Layers

Since allergens are proteins, they are subject to processing stresses, especially cooking. Yet that does not always reduce or eliminate allergenicity. For example, an allergic reaction to alliums, such as onion or garlic, can be mild or severe. Studies have found that cooked onions still can produce severe reactions—its allergens are heat-stable. Some companies still simply label them as “spices,” but garlic and onions must be individually declared on ingredient labels. Per US government regulations, they’ve traditionally been regarded as foods, while herbs and spices are able to be labelled collectively.

All’s FARE

Precautionary labels, such as “May contain…,” or “Manufactured in a facility that processes…” are voluntary, thus unregulated, and indicate there may be some risk of allergenicity, due to unintentional contamination of a food by particular allergens. The Food Allergy Research & Education organization (FARE) cautions that the federal government requires only that such labels not be a substitute for good manufacturing practices.

Accept Some Substitutions

While substitutions for gluten-containing grains abound and have become a multibillion dollar industry, manufacturers can avail themselves of substitutions for other allergens. Truffles contain a compound called androstenone that gives them noticeable garlic flavor. Truffle oil can be used to provide a garlic back note to soups and sauces.

Many dairy analogs are used as milk replacers in products such as beverages and coffee creamers, however for sauces and other heat-processed formulations, they can break down easily. Almond milk and oat milk tend to hold up better under processing conditions, although some added fibers, gums, or starches typically might be necessary to prevent separation.

Sunflower nut butter can be an effective replacement for peanut butter in some formulations, as can sesame paste (tahini), although sesame has recently been added to the list of common food allergens and so must still be declared as such on labels. Surimi is a tried-and-true replacement for shellfish, although care must be taken as some forms of the fish, typically pollack, are flavored with shellfish juice.