By an allergy, we mean an intensified or altered response by the body to foreign substances, caused by hypersensitivity of the immune system. Common allergic symptoms include rashes, redness of the skin and swelling, asthmatic breathing symptoms, itchy eyes or stomach troubles.
An allergy to alcohol itself – that is, ethanol – is extremely rare. The most typical symptom is sudden hives, which can easily escalate to an anaphylactic reaction (that is, sudden hypersensitivity). The volume of alcohol required to trigger a reaction is usually about 8–10 grams. One serving (for example, one bottle of beer or 12 cl of wine) contains 11–14 grams of pure alcohol.
Alcohol can also cause a sudden hypersensitivity reaction via non-allergic mechanisms, such as during colds and flus, when someone who is hungover goes jogging, or when someone otherwise exerts themselves enough to break out in a sweat.
Sudden flush from alcohol
Even a small amount of alcohol can cause flushing of the face and upper chest, which may last for several dozen minutes. This is not, however, an allergic reaction. Contributing factors include menopause, acne rosacea, sensitivity to flushing (hereditary) and stress in social situations.
Many people who are susceptible to headaches – and in particular those with allergies – often get a migraine-like headache from just one glass of red wine. This is one symptom of the so-called red wine headache syndrome. The syndrome also involves a bad hangover whose severity may be out of all proportion to the amount of wine consumed. Although not much is known about this syndrome, tannins are one suspected cause of a wine headache.
Many researchers believe that a wine headache is often psychological, caused by a prior experience of a severe wine hangover. Drinking just one glass of the same wine at a later date can then trigger a headache.
Substances that cause hypersensitivity and allergies
Sulphites, that is, sulphur compounds
Sulphur compounds are used in wine as preservatives. There are more sulphites in white wine than in red wine, and sweet white wines contain the most sulphites. Sulphites are used to prevent wine from oxidising.
Alko’s wine selection contains natural wines, which are made using either zero or minimal sulphites. Read more about natural wines.
Tannins are found in all plants, but grape skins and seeds contain more than average. Tannins are one of the suspected causes of a wine headache. The skins of red grapes are used in the production of red wine, and are only removed after fermentation. When making white wine, the grape skins are removed before the fermentation process begins.
The colourants added to beverages may cause allergic reactions and even sudden hypersensitivity. Colourants are used in, for example, red bitters.
The most important biological amine is histamine. It occurs throughout nature, and also in red and white wines. Biogenic amines can cause a hypersensitivity reaction or a headache. Alcohol increases the effect of amines, as it hinders the operation of the enzyme that breaks down amines.
In addition to the aforementioned substances, allergic and asthmatic symptoms may be caused by things such as yeasts, spices, quinine and cereals. Read more in Alko’s brochure on Additives in alcoholic beverages and hypersensitivity.
Additional information: Allergy, Skin and Asthma Federation