The following allergy information pertains to buckwheat flour and dust, not cleaned Buckwheat Hulls as used in Pillows sold by The Original Makura, Div. Hence caution is urged in purchasing low cost import pillows which may not use cleaned hulls. Prior to using cleaned hulls, there was approximately 0.5% (1 in 200 users) reported cases of mild (itchy throat, watery eyes etc.) to moderate allergic reactions (skin rash) in users of buckwheat hull pillows. After switching to hulls which have had buckwheat flour dust removed by a dry vacuum and sifting process, reported cases of mild allergic reactions dropped to approximately .016% (1 in 6000 users), and there have been no reported cases of moderate allergic reactions. There have been no reported cases of severe allergic reactions (asthma attacks, difficulty breathing, etc.) to using buckwheat hull pillows. This is based on empirical evidence in over 150,000 pillows sold by The Original Makura, Div. The following information was found somewhere on the net and is presented for your benefit, we make no evaluation based on the scientific accuracy of the information. ;
Allergy to Buckwheat
Department of Occupational and Environmental Medicine, University Hospital, S-753 31 Uppsala, Sweden
Airway exposure to organic dust from cereals may result in both allergic and non allergic airway diseases. In addition, food allergy to compounds in cereals, e.g. gluten, may occur. Grain dust lung is one of the oldest occupational diseases described in the old literature in Sweden. In 1555, the last Catholic archbishop of Sweden published the first map of Sweden and wrote a history of the Nordic peoples in Europe1. He noted the risk for throat and airway illness of the tresherer when separating the grain from the flails and the risk of damage to throat and other respiration. Though occupational health problems from exposure to grain dust is well known, the specific health hazards related to handling, processing, and consumption of buckwheat has not been well studied until this century.
Buckwheat (Fagopyrum esculentum) is not taxonomically related to wheat, but sometimes used as a substitute. Buckwheat can be cultivated under poorer circumstances than rice, and both grains and leaves can be used in food. This advantages of buckwheat can make it a crop of increased importance in the future. In Japan it is a common dish as in buckwheat noodles, buckwheat dumpling, and buckwheat bun, but is also used as pillow stuffing. In other countries it is often used as a baking material for cakes, or pancakes. In Sweden, it was widely used during the 16th century, but today it is used only in limited amounts as health food in Scandinavia.
Allergy to buckwheat was reported for the first time in the scientific literature in 19092. The pathomechanism of this allergy is type I, which means it is an IgE mediated immediate type reaction. Because of the potential allergic properties of buckwheat, exposure conditions during post harvest treatment, storage, and refining of buckwheat products should be controlled for to minimize the airborne exposure.
Review of the Literature on Buckwheat Allergy
Most of the literature on this topic consists of case reports, and some of them describe cases of children with food allergy. There are, however, only a few epidemiological studies available on occupational buckwheat allergy. In addition, there is scarce information available on occupational, or domestic, airborne exposure levels to airborne buckwheat allergens.
Case Studies on Buckwheat Allergy
In 1909, Smith described a case of buckwheat allergy, where an adult patient suffered from both symptoms of asthma, allergic rhinitis, urticaria, and angioeodema2. The allergic reactions could be provoked after ingestion of small amounts of buckwheat flour. In 1913, Peshkin demonstrated a positive skin prick test to an extract from buckwheat, in an allergic child3. In 1931, Rowe could demonstrate 27 positive skin prick reactions among 500 consecutive cases in USA (5.4% positive) among patients referred to his clinic4. Thirty years later, Horesh published another American study on buckwheat allergy in children5. He could identify 36 cases of buckwheat allergy at his clinic in Cleveland, USA out of a total of 514 patients. He evaluated the percentage buckwheat sensitive children to be 1% in his patient material. He also stated that the exposure to buckwheat allergens may increase in the USA, as the buckwheat will be more commonly used.
From the sixties and on, a series of Japanese studies on buckwheat allergy were published. In one early study, a single case of buckwheat allergy was described by Nakamura6. Matsamura reported on six cases of asthma, where the source of allergen exposure was buckwheat flour attached chaff used in pillows as stuff7.
An important Japanese research paper on buckwheat allergy was published by Nakamura et al. in 1974/19758. Nine cases of buckwheat allergy were thoroughly studied. Hypersensitive symptoms were asthmatic attacks, urticaria eruption, gastrointestinal disorders, nasal symptoms, and congestion of conjunctiva. Routes of exposure could be both by mouth and by airway exposure. The pathomechanism was type I, which means it is an IgE mediated immediate type reaction. The author also concluded that the antigenicity of buckwheat is extremely strong, and that hyposensitivity treatment with buckwheat extracts should no be applied because of the risk for severe and dangerous reactions.
In addition, Nakamura and Yamaguchi performed a national-wide scale questionnaire screening on buckwheat allergy in the whole of Japan9. They mailed questionnaires to every department of internal medicine, pediatrics, oto-rhino-pharyngo-laryngology, and dermatology in the university hospitals in the whole country. This survey resulted in 169 identified cases of buckwheat allergy. They were thoroughly examined with skin test, scratch test, nasal test, skin prick test, inhalation provocation test, dietary test, and measurement of eosinophilia in peripheral blood.
The majority (75% ) hade a positive eosinophili test. Most of the cases were young children, only 14% were adults, aged 20 years or more. It was also noted that the majority were males, and there was a male / female ratio of 1.64. Food allergy to buckwheat was the most common type of allergy, but as much as 60% also reported symptoms at exposure through the airways. The most common type of symptom was asthmatic attack in relation to buckwheat exposure, 139 cases (82% ) suffered from buckwheat asthma. Less common were nasal symptoms (23% ), eye symptoms (13% ), urticaria (45% ), and gastrointestinal symptoms (33% ). In 18 of the cases, anaphylactic shocks at exposure to the buckwheat allergen occured9.
Occupational Buckwheat Allergy
Allergy to buckwheat has been reported to be one cause of occupational asthma among workers in noodle shops in Japan10. In another Spanish case report, a case of occupational buckwheat allergy was examined and documented11. She developed sneezing, rhinorrhea and nasal itching shortly after she began her work with making buckwheat crepes. Four years later she got dyspnea, wheezing, and contact urticaria. In the next stage she got nausea, vomiting, gastric pain and urticaria a few minutes after she ate buckwheat crepes. They demonstrated IgE against buckwheat flour in the patient's serum by means of specific tests, e.g. histamine release test. The allergen seemed to be a thermostabile protein with a high molecular weight. The authors remark that although buckwheat flour is used in the baking industry in most western countries, few reports of allergy exist.
Schumacher and coworkers describe six cases of buckwheat allergy among adults in Switzerland12. Two of the cases were occupational asthma due to buckwheat exposure in a health food shop, and a bakery, respectively. Sensitization was proven by positive skin prick tests and specific IgE (RAST). In another case report from USA, buckwheat induced anaphylaxis after eating buckwheat crepes was demonstrated in a woman who had had an occupational exposure 4 years earlier13. She had manufactured cushions and pillows with fillings of wheat hulls and kapok fibers.
There is scarce information in the literature from epidemiological studies on manifestations of buckwheat allergy. In 1983, we published a study on 28 persons in a Swedish company importing, preparing and distributing plant products used in spices and in healthy food products14. The imported raw material arrived in sacks, and was packed in separate package rooms into smaller packets of weight 0.25-1 kg. Buckwheat, which caused most adverse reactions, were delivered in 25 kg sacks and was packed, but not grinded. In total all 14 men and 14 women, aged 17-65 years, participated in the study. The employment period ranged from two months to 20 years, and eight persons had worked less than one year. Twenty-five of the persons (89% ) were smokers. Thirteen persons experienced rhinitis, asthma, skin itching and conjunctivitis related to buckwheat exposure. The reactions usually came within one hour after exposure. Positive allergy tests (patch test, prick test or RAST test was seen in seven cases (28% ) of the 25 tested subjects. Atopic heredity (eczema, hay fever, asthma) was found in only 6 persons (21% ).
In the Swedish study, airborne dust levels were measured by personal sampling in the breathing zone of the workers, at different types of operations14. The highest dust levels were measured at grinding of chick peas and coriander (3.6 and 6.4 mg / m3, respectively). Lower dust exposure levels were measured at packing of buckwheat and rice (1.7 and 0.9 mg / m3, respectively). The dust exposure while packaging buckwheat was not high, as compared to existing occupational permissible exposure limit values (PEL) for organic dust in Sweden (5 mg / m3)15.
Conclusion and Recommendations
As indicated by several case reports, buckwheat contains very potent allergens, which may cause various types of allergic reactions, including asthma and anaphylactic shocks. The allergens seems to be a thermostabile proteins with a high molecular weight. The pathomechanism is type I, which means it is an IgE mediated immediate type reaction. Because the antigenicity of buckwheat is extremely strong, hyposensitivity treatment with buckwheat extracts should not be applied because of the risk for severe and dangerous reactions.
The lack of epidemiological studies on buckwheat allergy, makes it difficult to estimate the prevalence, or incidence, of allergic manifestations to buckwheat in the population in different countries. As indicated by available case-reports, a large proportion of the cases consist of allergic children, and food allergy is a common type of allergy. There are, however, many subject, both children and adults, with asthmatic reactions at airway exposure to low levels of buckwheat allergens. Domestic exposure during preparing of food may be one cause of this allergy, but allergen exposure from buckwheat used in pillows may also be of importance in some countries.
Occupational exposure to buckwheat may also be of importance, particularly for occupational asthma and allergic rhinitis. Since there is a lack of epidemiological studies in this field, and because health based selection of sensitized individuals could occur, there is a need for longitudinal studies on occupational buckwheat allergy. In occupations where dust exposure to buckwheat occurs, it is important to minimize the exposure. This could be done by encapsulation of the process, use of local exhaust ventilation, or by use of personal airway protection devices, e.g. disposable dust filters.
1. Olaus Magnus. Historia de gentibus septentrionalibus (Latin), 1555 . Translation (Swedish) : Historia om de nordiska folken (History of the Nordic People) (Almquist & Wiksell), 13(7) : 41, Uppsala-Stockholm, 1909.
2. Smith HL. Buckwheat Poisoning with Report of a Case in Man. Arch intern Med 1909 ; 3 : 350-359.
3. Peshkin MM. Asthma in children-etiology. Am J Dis Child 1926 ; 31 : 763.
4. Rowe AH. Individual food and drug allergies and their control. In : Rowe AH, ed Clinical Allergy, manifestations, diagnosis and treatment. Philadelphia : Lea & Febiger, 1937 : 563.
5. Horesh AJ : Buckwheat Sensitivity in Children. Ann Allergy 1972 ; 30 : 685-689.
6. Nakamura S, Yamaguchi M, Oishi M, Hayama T. Studies on the Buckwheat Allergose. Report 1 : On the Cases with the Buckwheat Allergose. Allergy and Immunology 1974 / 1975 ; 20 / 21 : pp 449-456.
7. Matsamura T, Tateno K, Yugami S, Kuroume T. Six cases of buckwheat asthma. J Asthma Res 1964 ; 1 : 219.
8. Nakamura S, Yamaguchi M, Oishi M, Hayama T. Studies on the Buckwheat allergose. Report 2 : On the cases with the Buckwheat Allergose. Allergie und Immunologie 1974 / 1975 ; 20 / 21 : 457-465.
9. Makamura S and Yamagushi M. Studies on buckwheat allergose. Report 2 : Clinical investigation on 169 cases with the buckwheat allergose gathered from the whole country of Japan. Allergie und Immunologie 1974 / 1975 ; 20 / 21 : 457-465.
10.Kobyyashi S. Different aspects of Occupational Asthma in Japan. In : Frazier CA (ed.) Occupational asthma. Van Nostrand Reinholt Company, New York, 1980, pp. 229-256.
11.Valdivieso R, Moneo I, Pola J, Munoz T, Zapata C, Hinojosa M, Losada E. Occupational asthma and contact urticaria caused by buckwheat flour. Ann Allergy 1989 ; 63 : 149-152.
12.Schumacher F, Schmid P, Wuthrich B. Zur Pizokel-allerie : ein beitrag uber die buckwiezenallergie. Schweiz Med Wochenschr 1993 ; 123 : 1559-1562. (in German with abstract in English)
13.Davidson AE, Passero MA, Settipane GA. Buckwheat induced anaphylaxis : a case report. Ann Allergy 1992 ; 69 : 439-440.
14.G the CJ, Wieslander G, Ancker K, Forsbeck M. Buckwheat Allergy : Health Food, an Inhalation Health Risk. Allergy 1983 ; 38 : 155-159.
15.National Swedish Board of Occupational Safety and Health. Code of Statutes. AFS 1993 : 9, Stockholm 1993. (in Swedish)
Current Advances in Buckwheat Research (1995) : 951 - 955