Grapes are in the Vitaceae family of plants. This family of plants includes multiple varieties of grapes.

The key allergen in grape is Vit v 1, this is a Lipid Transfer Protein (LTP). These proteins are resistant to heat and are found in many types of plants. Patients suffering from a more severe allergy to cooked fruit may be sensitised to this group of proteins.

Other allergens found in grapes include a profilin protein, a thaumatin protein and chintinase-like proteins.

A byproduct of winemaking is grapeseed oil, this is a vegetable oil made from the seeds of the grapes. All vegetable oils are highly processed, so are less likely to cause allergic reactions than the fresh or dried fruit.

When considering grape allergies you need to consider whether you are reacting to them in their fresh form, after they have been dried, to make sultanas and raisins or whether you have reacted to them in wine. Dried fruit and wine are both strongly linked with food intolerances, see section below.

Grapes themselves are low in histamine, but red wine is high in histamine. The amount of histamine increases as fruit dries, so sultanas and raisins should also be avoided if you are following a low histamine diet.

Wines and wine vinegars are also high in sulphites. Fresh grapes are low in sulphites, but the amount increases as they dry, so raisins and sultanas are not suitable for people following a low sulphite diet. Sulphites are inorganic salts used in preservations and have the potential to cause symptoms of food intolerance to those sensitive to sulphites, this food intolerance is more common in asthmatics. An improvement in symptoms can be made with a change to a low sulphite diet.

Grapes are a low FODMAP food, but wine, especially fermented wines are high. FODMAP stands for Fermentable oligosaccharides, disaccharides, monosaccharides and polyols. Foods high in FODMAPs can cause symptoms of food intolerance, affecting the gastro intestinal system and this can be mistaken for a true IgE food allergy.

Fresh grapes, dried raisins, dried sultanas and wine are all foods high in salicylates. Salicylates have the potential to cause worsening of asthma, swelling, itching and hives as well as food intolerance symptoms in people who are sensitive to salicylates.

Grapes are one of the few fruits to contain a moderate amount of lectins, another cause of food intolerance. Cooking foods with lectins makes them more digestible and can reduce the symptoms of food intolerance.

You can read more about Food Intolerances on the dedicated Food Intolerance Page.

You may be suffering from LTP Syndrome if you have reactions to various fruits, vegetables and nuts and your reactions continue to be severe after you have discarded the peel and have cooked the food.

Allergies to the protein chitinase can sometimes be linked to Latex Food Syndrome. Profilin proteins are also linked to this syndrome, but to a lesser degree as profilin proteins are more easily damaged by extremes of heat and processing.

Profilin protein allergies can also be linked to Celery Mugwort Spice Syndrome. The symptoms associated with this syndrome are often referred to as OAS (Oral Allergy Syndrome) as it mostly affects people who already suffer from pollen allergies and seasonal rhinitis, but also includes a lot of oral symptoms like an itchy mouth, lips, tongue and throat.

Common foods involved in LTP allergy include kiwi, strawberries, sunflower seeds, walnut, apple, mulberry, banana, pea, apricot, cherry, plum, almond, peach pomegranate, raspberry, tomato, grape, celery, peanut, asparagus, cabbage, broccoli, chestnut, lemon, tangerine, orange, hazelnut, lettuce, lentils, lupin, green bean, pear, mustard, wheat and maize.

Other foods containing profilin include apples, cherry, corn, figs, kiwi, melon, mustard, plum, tomato and wheat.

Other foods containing thaumatin include apple, banana, pepper, chilli, celery, cherry, elderberry, elderflower, garlic, kiwi, peach and plantain.

Chitinase is a protein also found in avocado, banana, beetroot, cashew, chard, chestnut, coffee, corn, kiwi, mango, plantain, pomegranate, spinach and tamarind.

Note that none of these food lists are exhaustive, please visit the cross reactivity tools for the most up to date allergen records.

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