Your complexion can reveal a lot more about your health than simply whether you are dehydrated or have spent too much time in the sun. In fact, how your skin looks can be a strong indication of whether you’re making the best food choices for your body. That’s because food allergies and intolerances can compromise the digestive and immune systems, giving rise to acne, eczema, rosacea, and other bothersome skin conditions.

Food allergies and food intolerances are not the same, but they can both wreak havoc on the skin. A food allergy arises when the body mistakes a protein, starch, or other component of a food as a foreign invader. To combat the allergen, the immune system releases disease-fighting antibodies and other chemicals, including histamine, in an effort to expel the “invader” from your body. In addition to causing potentially life-threatening symptoms such as shortness of breath, the release of histamine can produce hives, blemishes, or the inflammation and itching associated with eczema.

A food intolerance, on the other hand, can arise because a person lacks the enzymes necessary to properly digest certain proteins found in food, as is the case in lactose intolerance, or their body simply cannot break down certain food components such as the flavor enhancer monosodium glutamate (MSG) or the sulfites that are often in red wine. These toxic, undigested food particles then move through the gut wall into the bloodstream and are finally filtered through the liver and kidneys — a process that is quite taxing on the body and has been linked to the occurrence of acne and eczema.

Although even the most common food allergens — shellfish, peanuts, and eggs — are thought to only affect about one percent of adults, food intolerances are much more common and on the rise. If you think your skin problems might be a product of your diet, try keeping a food diary of what you eat to correlate with any symptoms. Or, ask your healthcare practitioner about skin or blood tests that pinpoint your personal trigger foods.