Many people experience uncomfortable symptoms after drinking red wine, such as a headache or flushing, yet they can enjoy white wine without issue. This common experience leads to the question of whether a person can be selectively sensitive to the red varietal. While these reactions are often called “allergies,” they are typically a sensitivity or intolerance to specific compounds found in higher concentrations only in red wine. The distinct chemical composition of red and white wine, determined by their production methods, is the key to understanding this differential reaction.
The Distinctive Role of Tannins and Phenolics
Red wine contains high levels of tannins and other phenolic compounds, which are largely responsible for the color, structure, and characteristic drying sensation in the mouth. These compounds are naturally extracted from the grape skins, seeds, and stems, which remain in contact with the fermenting juice for weeks during red wine production. White wine fermentation, conversely, involves pressing the grapes and removing the skins almost immediately, resulting in a much lower concentration of these elements.
The total phenolic content in red wine can exceed 1,000 milligrams per liter, while white wine usually contains less than 250 milligrams per liter. Sensitivity to these compounds is proposed to trigger symptoms like headaches, flushing, and nausea in some individuals. One theory suggests that certain phenolics can interfere with enzymes that regulate blood vessel dilation, leading to the rapid onset of a headache.
Histamine Content and Intolerance
Another significant difference between the two wine types lies in their biogenic amine content, particularly histamine. Histamine is a naturally occurring compound that is a byproduct of the fermentation process, specifically the malolactic conversion, which is nearly universal in red winemaking. Red wines typically contain significantly higher concentrations of histamine (60 to 3,800 micrograms per liter) compared to white wines, which rarely exceed 120 micrograms per liter.
The mechanism behind histamine-induced reactions is a metabolic intolerance, not an immune response. The body relies on the enzyme diamine oxidase (DAO) to break down ingested histamine. If a person has a deficiency in DAO, consuming histamine-rich red wine can overwhelm the body’s ability to process it. Symptoms of this intolerance include migraines, nasal congestion, itching, and digestive upset. Furthermore, the alcohol itself can temporarily inhibit DAO activity, exacerbating the reaction.
Clarifying Sulfite Sensitivity
Sulfite sensitivity is frequently, though incorrectly, blamed for adverse reactions to red wine. Sulfites are inorganic salts used as a preservative in nearly all wines and many other foods, preventing oxidation and bacterial growth. White wines often contain equal or greater amounts of added sulfites than red wines. This is because white wine lacks the high concentration of naturally occurring tannins that act as a preservative in red wine. Therefore, if sulfites were the primary trigger, a person would likely react as strongly, or perhaps more strongly, to white wine. While sulfite sensitivity is a genuine condition, typically manifesting as asthma-like symptoms, it is unlikely to be the cause of a reaction that occurs only with red wine.
Differentiating True Allergy from Intolerance
Understanding the difference between a true allergy and a chemical intolerance is important for identifying the cause of a red wine reaction. A true allergy is an IgE-mediated immune response, which is a systemic reaction triggered by specific proteins, such as residual grape or yeast proteins. True allergic reactions are rare and their symptoms are typically severe, including hives, swelling, difficulty breathing, and potentially anaphylaxis.
Conversely, an intolerance is a non-immune system response, often metabolic or chemical, and is the more common cause of wine-related symptoms. When a reaction is confined to red wine, it is almost certainly a sensitivity to the higher concentrations of tannins or histamines. The symptoms of intolerance, such as headaches, flushing, and digestive distress, are uncomfortable but generally not life-threatening, confirming the reaction is a chemical sensitivity, not a true allergy.