A food allergy is an immune system reaction to certain foods, where the body mistakenly identifies a normally harmless food protein as a threat, leading to various symptoms that can range from mild to life-threatening. According to FDA regulations, Chinese medicinal herbal preparations are considered a type of food that may cause an allergic reaction in susceptible individuals, either to a particular herb or to other ingredients found in the preparation, such as processing adjuncts or excipients used in manufacturing. Mayway Herbs, in pursuit of its goals of quality and transparency, has endeavored to make sure that we disclose all major allergens present in our products to our practitioner customers and their patients. Currently, all Mayway products comply with FDA allergen labeling regulations that took effect January 1, 2023, and the allergen information appears on our product labels and individual product information pages located on our website.
Food Allergens
Food allergies occur when the body's immune system reacts to certain proteins in food. Food allergic reactions vary in severity from mild symptoms involving hives and lip swelling to severe, life-threatening symptoms, often called anaphylaxis, that may involve fatal respiratory problems and shock. While promising prevention and therapeutic strategies are being developed, food allergies currently cannot be cured. Early recognition and learning how to manage food allergies, including which foods to avoid, are important measures to prevent serious health consequences.
More than 170 foods have been reported to cause food allergy reactions in the U.S. In 2004, Congress passed the Food Allergen Labeling and Consumer Protection Act (FALCPA). This law identified eight foods as major food allergens: milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, and soybeans which represent at least 90 percent of the serious food allergy reactions. In 2021, sesame was added as the ninth major food allergen. So that consumers who are allergic to foods and their caregivers can identify and avoid foods that contain major food allergens, FALCPA requires that foods or ingredients that contain a "major food allergen" be specifically labeled with the name of the allergen source. Inadequate warning of the presence of one of the major food allergens is one of the most frequent reasons for food recalls ordered by the FDA.
Approximately 33 million people in the United States have at least one food allergy. This means that nearly 11 percent of adults aged 18 or older (~26 million people) have at least one food allergy and nearly 8 percent of children (>6 million) have food allergies. That’s about one in 13 children, or roughly two in every classroom. About 40 percent of children with food allergies have multiple food allergies, that is, more than one food to which they’re allergic.
Symptoms of a food allergy include:
- Hives
- Hoarse voice
- Wheezing
- Swelling, especially of the eyelids, face, lips, and tongue
- Trouble swallowing or breathing due to swelling in the throat
- Itching of the mouth, throat, eyes, skin, or any other area
- Dizziness, lightheadedness, fainting, or feelings of impending doom
- Nasal congestion, runny nose
- Stomach cramps, diarrhea, nausea, or vomiting
Severe allergic reactions can happen immediately or within two hours after eating a food allergen, e.g., anaphylaxis, which can be life threatening. Anaphylaxis is characterized by vasodilation resulting in decreased blood pressure, smooth muscle contraction resulting in shortness of breath, and hives, caused by hypersensitivity induced by a secondary exposure to a foreign substance, such as a drug or protein, after an initial sensitizing exposure. Rapid treatment with epinephrine (adrenaline) within minutes of the onset of anaphylaxis symptoms may be necessary and crucial to successfully treating an anaphylactic reaction. Caregivers or individuals with known allergies may carry a self-injectable epinephrine device (available by prescription).
The Major Allergens
Milk
Cow’s milk allergy is the most common food allergy in infants and young children (~2.5% under age three). Even though most children eventually outgrow their allergy to milk, milk allergies are also among the most common food allergies in adults. Primarily, this is an allergic response to milk proteins, whey and casein. This is commonly discovered when infants are artificially fed cow’s milk or when transiting to cow’s milk as youngsters. In addition to an allergy to milk proteins, some individuals may be lactose intolerant, which is not really an allergy. These people have deficiency in the enzyme (lactase) necessary to break down the natural disaccharide, lactose, present in milk.
None of Mayway Herbs’ products contain milk or milk-derived products.
Egg
Egg allergies are among the most common food allergies in infants and young children (~2%), but is less common in older children and adults. Although some individuals remain allergic to eggs throughout their lives, most children eventually outgrow their allergy to eggs (71% by 6 years of age). Chicken eggs are the most common cause of an egg allergy. However, other animal eggs, including duck, turkey or quail, may also cause the immune system to react. The main egg allergy proteins include: ovomucoid, ovotransferrin, ovalbumin, and lysozyme. Ovalbumin breaks down at high temperatures, so individuals that are only allergic to that protein may tolerate cooked eggs without developing an allergic reaction.
None of Mayway Herbs’ products contain eggs or egg-derived products.
Peanuts
Peanut (Arachis hypogaea) allergy is the most common food allergy in children under age 18 (~2%) and the third-most common food allergy in adults. Peanuts are not truly nuts, but rather legumes. Most individuals with peanut allergy can tolerate other legumes, such as peas, soybeans, lentils and chickpeas. The majority of individuals with peanut allergies are able to tolerate true tree nuts. The allergy is to a group of seed storage proteins called Ara h. Peanut allergy is usually lifelong: only about 20 percent of children with peanut allergy outgrow it over time.
None of Mayway Herbs’ products contain peanuts or peanut-derived products.
Fish
Finned fish food allergy exists within the U.S. population at a prevalence of 1% of the population. In one study, salmon, tuna, catfish and cod were the fish to which people most commonly reported allergic reactions. About 40 percent of people with fish allergy experience their first allergic reaction as adults.
None of Mayway Herbs’ products contain fish or fish-derived products.
Shellfish
Shellfish allergies are one of the most common food allergies in adults and among the most common food allergies in children. Approximately 2% of the U.S. population reports an allergy to shellfish. Shellfish allergies are usually lifelong. About 60 percent of people with shellfish allergy experience their first allergic reaction as adults. There are two groups of shellfish: crustaceans (such as shrimp, prawns, crab, crayfish, krill, and lobster) and mollusks/bivalves (such as clams, mussels, oysters, scallops, octopus, squid, abalone, snail). Allergy to crustaceans is much more common than allergy to mollusks, with shrimp being the most common shellfish allergen for both children and adults.
While crustacean shellfish are one of the nine major allergens that must be listed in plain language on packaged foods sold in the U.S., products containing mollusks are not required to be labeled in the U.S. at this time. This contrasts with the EU, UK, Canada, and Australia that require labeling of both potential allergens.
None of Mayway Herbs’ products contain crustacean shellfish or derived products. Some products contain ‘herbs’ derived from mollusks/bivalves, e.g., Oyster shell/ Mu Li /Concha Ostreae and Abalone shell/ Shi Jue Ming/ Haliotis diversicolor.
Tree nuts
Tree nut allergies are among the most common food allergies in both children and adults (2-3%). This category has caused confusion in the past, and the FDA has revised the list several times. Not all nuts from all trees are included in this category. The six tree nut allergies most commonly reported by children and adults are allergies to walnuts, almonds, hazelnuts, pecans, cashews, and pistachios. Approximately 50% of children that are allergic to one tree nut are allergic to another tree nut. Most children who are allergic to one or more tree nuts do not outgrow their tree nut allergy.
The US FDA recognizes 12 types of tree nuts that require allergen labeling. These include:
- Almond
- Black walnut
- Brazil nut
- California walnut
- Cashew
- Filbert (hazelnut)
- Heartnut (Japanese walnut)
- Macadamia nut (Bush nut)
- Pecan
- Pine nut (Pinon nut)
- Pistachio
- English and Persian walnut
The FDA now specifically excludes the following tree nut species from the list of "tree nuts” that must follow food allergen labeling requirements:
- Coconut
- Cola (kola) nut
- Beech nut
- Butternut
- Chestnut
- Chinquapin
- Ginkgo nut
- Hickory nut
- Palm nut
- Pili nut
- Shea or shea nut
Some Mayway products contain tree nuts, including the herbs Hú Táo Rén (胡桃仁)/ walnut and Sōng Zǐ Rén (松子仁) / pine nut.
Products containing tree nuts:
| Hu tao ren/ Juglans regia seed |
Walnut |
| Hu tao ren/ Juglans regia seed |
Walnut |
| Hu tao ren/ Juglans regia seed |
Walnut |
| Cerebral Tonic Tablets/ Bu Nao Pian |
Walnut |
| Five Seed Teapills/ Wu Ren Wan |
Pine Nut |
| Ping Chuan Pills/ Ping Chuan Wan |
Walnut |
Soy
Soy allergy is more common in infants (approximately 0.4% in the U.S.) and young children than in older children. Most children eventually outgrow their allergy to soy, although some individuals remain allergic to soy throughout their lives. Soybeans are members of the legume family. Beans, peas, lentils and peanuts are also legumes. While it is rare for peanut allergic patients to react to soy, the reverse is not true. One study found that up to 88% of soy-allergic patients had peanut allergy or were significantly sensitized to peanut. Individuals with soy allergies were also more likely to be allergic or sensitized to other major allergens including peanuts, tree nuts, eggs, milk and sesame than to non-peanut legumes such as beans, peas, and lentils.
Some Mayway products contain soy including the ‘herb’, Dàn dòu chǐ /淡豆豉 /Glycine max, known as ‘prepared soybean’, which is also used to process certain herbs to alter their medicinal value.
Products containing soy:
- Dan Dou Chi/ Glycine max seed (prepared)
- He Shou Wu (zhi)/ Polygonum multiflora root (prep.)
- Yin Chiao / Qiao Pian/San
Ē Jiāo (阿胶), Guī Bǎn Jiāo (龟板胶), and Lù Jiǎo Jiāo (鹿角胶) are traditional Chinese herbs processed using soybean oil. Because this soybean oil is refined and expeller-pressed, it is highly unlikely to contain the soy proteins that typically cause allergic reactions. However, some individuals may be sensitive to even trace amounts of soy protein that could potentially be present.
Sesame
Sesame is the ninth most common food allergy among children and adults in the U.S. (~0.25%). The edible seeds of the sesame plant are a common ingredient in cuisines around the world, from baked goods to sushi. Several reports suggest this allergy has increased significantly over the past two decades.
Hēi Zhī Má (黑芝麻) /black sesame seed / Semen Sesamum Indicum Nigrum is found in some Mayway products.
Products containing sesame:
- Hei Zhi Ma/ Sesamum indicum seed
- Qing Zao Jiu Fei San
- Xiao Feng San, extract granule
- The Great Windkeeper Teapills/ Xiao Feng Wan
Wheat
Wheat allergy is most often reported in young children and may affect up to 1% of children in the US. One study found that two-thirds of children with a wheat allergy outgrow it by age 12. However, some individuals remain allergic to wheat throughout their lives. Wheat is the most widely grown crop with more than 25,000 different cultivars produced globally. One interesting aspect of FDA labeling regulations is that wheat containing products require disclosure, but gluten-containing products do not, in contrast to the EU, UK, Canada, and Australia.
Wheat allergy and celiac disease are both adverse food reactions, but their underlying causes are very different. Wheat allergy results from an adverse immunologic (IgE-mediated) reaction to several proteins in wheat, and reactions can cause typical allergy symptoms involving the skin, gastrointestinal tract, respiratory system, and anaphylaxis in some individuals. Wheat contains several types of proteins, primarily categorized into gluten-forming proteins (like gliadin and glutenin) and non-gluten-forming wheat proteins (such as albumins and globulins).
Celiac disease is an immune-mediated disease. Antibodies are produced in response to the presence of certain gluten proteins resulting in inflammation and damage to the lining of the small intestine. Studies suggest that ‘gluten’, the main protein fraction of wheat, isn’t completely digested, and these ‘digestive remnants’, often polypeptides, are what initiates an immune reaction in the small intestine in those with celiac disease. Gluten refers to two structural proteins found in wheat: gliadin, which provides extensibility in dough (the ability to stretch), and glutenin, which provides elasticity (the ability to recoil). These prolamin proteins do not exist per se in dry flour but are formed by hydration when water is added to flour and mechanical energy is added by kneading. Many symptoms involve the gastrointestinal tract (e.g., diarrhea, constipation, weight loss, abdominal pain and bloating). Other symptoms can include skin rashes and disorders that result from nutrient deficiencies. The estimated global prevalence of celiac disease is 1%, similar to wheat allergy. Gluten proteins are found in all wheat cultivars, rye, barley, triticale, malted grains, malt vinegar, and brewer’s yeast. There is some evidence that ‘ancient grains’ such as einkorn, khoransan, emmer, spelt, and others may have less gluten than modern wheat. The FDA requires that products that are labeled ‘gluten-free’ must be tested at a level of less than 20 ppm of gluten, and importantly, some celiacs may respond to gluten in foods that contain any amount of gluten.
Another increasingly prevalent condition in the US is wheat intolerance, sometimes called wheat sensitivity. Wheat intolerance often presents in those who suffer from irritable bowel syndrome (IBS), a common GI motility disorder, as well as in those with nonceliac gluten sensitivity (NCGS). IBS is the most common diagnosis made by gastroenterologists, affecting up to one in five people in the United States. Wheat intolerance is sometimes referred to as ‘nonceliac wheat sensitivity.’
Amylase/trypsin inhibitors (ATIs) are among the nongluten proteins found in wheat. ATIs have potent proinflammatory effects and might be involved with the onset and perpetuation of celiac disease and other nonceliac inflammatory diseases of the GI tract. ATIs have long been known to contribute to IgE-mediated allergy (notably Bakers' asthma), but interest has increased since 2012 when they were shown to be able to trigger the innate immune system, with attention focused on their role in celiac disease which affects about 1% of the population and, more recently, in non-coeliac wheat sensitivity which may affect up to 10% of the population.
Another suspect is fructans, a carbohydrate fraction of wheat, which is a known IBS trigger. Wheat is one of the most fertile sources of fructans in the Western diet. Fructans are nondigestible and nonabsorbable by the human GI tract and upon reaching the colon, are fermentable by resident bacteria. In susceptible individuals, like those with IBS, the byproducts of fermentation, gas and short-chain fatty acids can stimulate a wide range of GI symptoms.” There are other carbohydrates that are poorly absorbed in the small intestine known as FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols). These biochemicals include short-chain oligosaccharide polymers of fructose (the aforementioned fructans), galacto-oligosaccharides (stachyose, raffinose), disaccharides (especially lactose), monosaccharides (especially fructose), and sugar alcohols (polyols), such as sorbitol, mannitol, xylitol, and maltitol. It can be quite challenging to determine which of these chemicals are responsible for water retention, gas production, intestinal inflammation, and discomfort. Most FODMAPs are naturally present in food and the human diet, but the polyols/sugar alcohols may be added artificially in commercially prepared foods and beverages, especially in foods that are lower in calories in an effort to avoid the use of ‘sugar’.
Many Mayway products contain a type of wheat or are processed with wheat bran (according to standards defined in the Chinese Pharmacopeia or Materia Medica).
The herb, Fú Xiǎo Mài (浮小麦), commonly known as floating wheat grain or floating light wheat grain, is a medicinal substance used in Chinese medicine and is derived from a type of wheat.
Products containing wheat:
- Fu Xiao Mai/ Triticum aestivum fruit
- Gan Mai Da Zao San, extract granule
- An Shui Wan Teapills/ An Shui Wan
- Serene Spirit Teapills/ Gan Mai Da Zao Wan
Shén Qū (神曲)/ Massa fermenta, commonly known as “medicated leaven,” is a traditional Chinese combination medicinal ingredient that is traditionally produced using wheat as one of the primary ingredients.
Products containing Shen Qu:
- Shen Qu/ Massa fermenta
- Bao He Wan/San
- Curing Pills/ Kang Ning Wan/San
- Yue Ju San
- An Mien Pian Tablets/ An Mien Pian
- Bao He Teapills/ Bao He Wan
- Zi Sheng Teapills/ Zi Sheng Wan
It is important to understand there are numerous Chinese herbs and medicinal herbal products that include herbs that have undergone pào zhì 炮制/ traditional processing before being used medicinally.
A very common process is the roasting of an herb in wheat bran (fū chǎo 麸炒). The herbs are added to a preheated wok containing wheat bran until the herbs turn slightly yellow. Then, the bran is sifted from the herbs before being used. The procedure is intended to increase the Qi tonifying function of the herb and to protect the Yin. Several biochemicals are present on the surface of certain herbs, including aldehydes and ketones, which can be drying, potentially damaging the Yin. Common herbs subject to this processing include, Bai zhu 白朮/ Atractylodes macrocephala rhizome, Cang zhu 蒼朮/ Atractylodes lancea rhizome, Chen pi 陳皮/ Citrus reticulata peel, and Zhi shi 枳實/ Citrus aurantium fruit (immature), among others.
Among Mayway’s products, seventy-five contain herbs that have been processed with wheat bran. A comprehensive list can be found on Mayway’s website here. This information will be found on each product’s label, which will bear the words: “Contains Wheat”, in compliance with FDA requirements. The information can also be found in the product’s ingredient list on the product’s information page on the website.
All Mayway products have been individually tested by batch for the presence of gluten using ELISA, which is a method designed to find gluten at low levels. For those testing positive, the results are published on each product’s information page in the lower left corner of the page under the heading, “Product Attachments”. For example, see: “Free and Easy Wanderer”. Note that some products that are known to contain wheat may test at less than 20 ppm, which makes them technically ‘wheat-free’. The upper limit of the test method is 80 ppm and values that are found to be much higher are expressed as > 80 ppm.
Another source of potential wheat protein adulteration may involve processing using commercially available Huang jiu 黄酒 /Yellow wine or Xiāng cù 香醋/ ‘Rice’ vinegar. Mayway Herbs has specified to its manufacturers that only wheat-free and barley-free products can be used in the production of products and that all liquid adjuncts must be tested before use to ensure that there is no wheat adulteration from these sources.
Since our manufacturers strictly adhere to Chinese Pharmacopeia and Materia Medica standards, Mayway accepts that many of our products will present a risk to celiacs and those who have a wheat intolerance. When this is a concern for practitioners or patients, Mayway suggests that nearly all our products can be custom-formulated in our Herb Dispensary using either our sulfite-free, raw herbs or with single herb, extract granules.
Alpha-gal
Finally, a quick note about a relatively new food allergy that is expanding its range and prevalence in the US, Alpha-gal syndrome (AGS). Alpha-gal allergy is commonly known as mammalian meat allergy although ‘meat’ is not the only source. Alpha-gal refers to galactose-α-1,3-galactose, which is a disaccharide formed from two galactose molecules. Alpha-gal (AG) is found in most mammalian cell membranes, but not in humans, and since it is missing from human cells, it is recognized by the immune system as a xenobiotic. AG is one of the few antigens encountered in human medical physiology that is a carbohydrate and not a protein. Alpha-gal is present in all foods and ingredients made from beef, pork, lamb, venison, rabbit, and other mammalian sources, including gelatin and milk. AGS is a tick-borne condition, primarily the Lone Star Tick. Twenty-eight Mayway products either contain individual medicinal ‘herbs’ or are prepared with animal products that may contain Alpha-gal.
Mayway published an article about Alpha-gal syndrome in June 2026, which lists products that may contain Alpha-gal and can be found here.
References
- Allen KJ, et al., "Precautionary labelling of foods for allergen content: are we ready for a global framework?". The World Allergy Organization Journal. 7 (1) 10. doi:10.1186/1939-4551-7-10
- “Allergens”, FAQ, Mayway Website, https://www.mayway.com/pages/faq
- “Allergies”, American Academy of Allergy, Asthma & Immunology, https://www.aaaai.org/tools-for-the-public/conditions-library/allergies
- “Allergies”, The Cleveland Clinic, https://my.clevelandclinic.org/health/diseases/8610-allergies
- FDA, “Food Allergies”, https://www.fda.gov/food/nutrition-food-labeling-and-critical-foods/food-allergies
- “Update to FDA Guidance for Food Allergen Labeling”, Food Allergy Research and Education, Feb 2025, https://www.foodallergy.org/fare-blog/update-fda-guidance-food-allergen-labeling
- FDA, Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA), https://www.fda.gov/food/food-allergensgluten-free-guidance-documents-regulatory-information/food-allergen-labeling-and-consumer-protection-act-2004-falcpa
- “Food Allergy“, https://medlineplus.gov/ency/article/000817.htm
- “Food Allergy Facts and Statistics for the U.S.”, Food Allergy Research & Education, 2024, https://www.foodallergy.org/sites/default/files/2024-07/FARE%20Food%20Allergy%20Facts%20and%20Statistics_April2024.pdf
- Geisslitz, S., et al., “Wheat amylase/trypsin inhibitors (ATIs): occurrence, function and health aspects”, European Journal of Nutrition, Mar 2022, https://pmc.ncbi.nlm.nih.gov/articles/PMC9363355/
- Geisslitz, S., et al., “Wheat ATIs: Characteristics and Role in Human Disease” Frontiers in Nutrition, May 2021, https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2021.667370/full
- Questions and Answers Regarding Food Allergens, Including the Food Allergen Labeling Requirements of the Federal Food, Drug, and Cosmetic Act (Edition 5): Guidance for Industry, American Herbal Products Association, 2025, https://www.ahpa.org/Files/Document%20Library/AHPA%20Guidance%20Documents/Packaging%20and%20Labeling/FDA-Guidance-Jan2025-AllergenLabelingQA-12292024.pdf
- Scarlata, K., “What’s Behind Wheat Sensitivities?”, Today’s Dietician, May 2017, https://www.todaysdietitian.com/whats-behind-wheat-sensitivities/
- “Sources of Gluten” Celiac Disease Foundation, https://celiac.org/what-is-gluten/sources-of-gluten/
- “Treatments & Management”, Beyond Alpha-gal, https://www.beyondalphagal.org/treatments
- “What Makes Up Gluten: Gliadin, Glutenin, and Formation”, Science Pedia, Apr 2026, https://sciencepedia.blog/what-makes-up-gluten-gliadin-glutenin-formation
