Cereals containing gluten
Celiac disease and allergy to cereals e.g. wheat allergy are two different diagnoses. Individuals suffering from celiac disease must avoid gluten which is a protein found in wheat, rye and barley. Gluten causes damage to the small intestine of individuals with celiac disease. Individuals suffering from wheat allergy can react with symptoms like vomiting, eczema, asthma and anaphylactic shock to wheat proteins.
Celiac disease
Celiac disease or gluten intolerance is an autoimmune disease triggered by gluten, i.e. proteins present in wheat, rye and barley. The gluten proteins cause an inflammation of the mucosa in the small intestine leading to flattening of the mucosa and, when the illness is untreated, to malnutrition.
Celiac disease is a life-long, permanent intolerance to gluten. Cereals like wheat, rye and barley must be excluded from the diet. As alternatives, products labelled “gluten-free” or “very low gluten” can be used instead. The “gluten-free” products are often based on i.e. maize, rice, oat, millet or buckwheat. The products labelled “gluten-free” or “very low gluten” can also be based on cereals, which have been rendered gluten-free, like wheat starch.
Rules for labelling foods with "gluten-free" and "very low gluten" are given in Commission regulation (EU) No 828/2014.
Pure oat, which is not contaminated with gluten-containing cereals, can be included in the gluten-free diet. A number of clinical studies indicate that most people (adults and children) with celiac disease tolerate oat.
Allergy to cereals
Wheat and other cereals can also cause IgE-mediated allergic reactions. Such reactions are immediate or delayed after ingestion and their severity varies from mild to very severe like anaphylaxis. Gluten-free products i.e. those with a gluten level below 20 mg/kg are considered to be well tolerated by most people with IgE-mediated allergy to cereals.
Labelling
The presence of cereals containing gluten (i.e. wheat, spelt, khorasan wheat, rye, barley, oat or their hybridized strains) and products thereof must always be declared, see further in the Food Information Regulation (EC) no 1169/2011.
Rules for labelling foods with "gluten-free" and "very low gluten" are given in Commission regulation (EU) No 828/2014.
Products labelled "free from" an allergen refers to consumer groups with special medical sensitivity to such ingredients. The labelling is voluntary but must be relevant (not misleading). Products with "free from" labelling placed on the market after October 2018 need to be notified to the Swedish Food Agency.
LIVSFS 2014:4 - Föreskrifter om livsmedelsinformation (In Swedish)
Glutenfria, laktosfria och andra "fri från"-livsmedel - (In Swedish)
Examples of methods of analysis
In the Codex standard 118-1979, revised in 2008, general criteria for analysing gluten is described. The enzyme-linked immuno assay (ELISA) R5 method is listed as a method for determining gluten concetration. The limit of quantification is 5 mg gluten/kg (ppm). The quantification limit is not low enough to quantify concentrations of gluten that can cause reactions in one percent of the most sensitive allergic consumers when food that are consumed in large quantities are analysed.
Fermented foods like beer should be analyzed with a competitive ELISA.
Accredited methods should be used in official control. The Swedish Food Agency is accredited for analysis of gluten in food including fermented food.
Celiac reactions on cereals / Doses
The concentrations of gluten proteins that have been detected in food products causing reactions among individuals with celiac disease are listed below. The food and the descriptions of the reactions have been sent to the Swedish Food Agency by the health care or by control authorities.
| Food | Amount consumed | Gluten conc. mg/kg | Estimated dose | Age |
|---|---|---|---|---|
| Pasta* | 50 g | 10 000 | 500 mg | 9 years |
| Biscuit | 50 g | 140 | 7 mg | Adult |
| Snacks | 10-50 g | 10 000 | 100-500 mg | 6 years |
| Chocolate | 100-200 g | 70 | 7-14 mg | Adult |
| Wafer | 100-150 g | 70 | 7-10 mg | Child |
| Ice coon | 10 g | 860 | 8,6 mg | 7 years** |
* The same product causing the allergic reaction below ** Child who consumes only products without wheat starch
Allergic reaction to cereals / Doses
The lowest dose of gluten protein that elicitates an allergic reaction is not known. However, individual oral food challenge data can be compiled in order to estimate the proportion of the allergic population that would be likely to react to a certain dose of an allergen. The Swedish Food Agency has used such published data and developed a guide on how to calculate the risk of allergic reactions to certain concentrations of e.g. wheat protein. The guide L 2022 nr 13 is in English and can be reached below.
Below are also some allergic reactions to foods with undeclared wheat listed. The reactions are listed as examples of reations in order to illustrate that allergic reactions have been caused by different kind of foods and different doses.
| Food | Amount consumed | Gluten conc. mg/kg | Estimated dose | Age |
|---|---|---|---|---|
| Pasta* | 50 g | 10 000 | 500 mg | 8 years |
| Oatbased vanilla sauce | 70 g | 33 | 2.3 mg | 11 years |
* The same product causing the allergic reaction above
