Congestion occurs due heightened mucus production -- typically in your sinuses, nasal cavities or throat -- in response to an irritant or illness. Causes include airborne allergens, viruses such as the common cold and reactions to certain foods. While any food to which you have an allergy or sensitivity can cause congestion, individuals with no known food allergies may feel congested after eating certain foods.
Sugar
You may experience an adverse reaction to sugar, particularly if you have a sugar intolerance. Mucus buildup and congestion are symptoms of a sugar intolerance, and you may even exhibit asthma-like symptoms during a more severe reaction. This condition occurs when your digestive system lacks the enzymes necessary to process sugar, or when you consume more than you can comfortably digest. You may take asthma medication or a decongestant to treat your symptoms, but talk to your doctor or nutritionist about your diet in order to address the cause.
Wheat Protein and Gluten
Wheat protein may trigger antibody production from your immune system. As these antibodies attack the offending proteins, they produce the symptoms of a food allergy. Any of the proteins in wheat may cause this reaction. Wheat allergy is similar to celiac disease and gluten allergies, but these conditions center around a specific protein, gluten. In celiac disease, the immune system reacts specifically to the gluten in wheat.
Milk and Dairy Products
Although research has widely dispelled the belief that all milk causes some level of congestion, some studies show that certain types of milk may uphold this reputation. Milk that contains a specific protein stimulates mucus production within your digestive tract. The affected mucus glands are similar to those within your nose or throat, so the protein may also affect them. The extent to which you become congested after drinking milk depends on your sensitivity to the presence of the protein beta-CM-7, as well as any existing respiratory conditions you may already have, such as asthma.
Alcohol
Alcohol consumption yields many potential side effects, and congestion can be among them. Alcohol itself produces a heightened phlegm response. Your drinking habits may increase or diminish this response, depending on the type of alcohol you consume. For example, if you drink beer made with wheat or hops, you may react to the proteins in these ingredients as well as to the alcohol itself.
Elimination Diet
If you suspect that some part of your diet is causing congestion or an allergic reaction, you can adopt an elimination diet and try to determine the cause. In an elimination diet, you simply remove your suspected dietary cause and, if the symptoms do not abate, you eliminate another until you discover the offending food. The prevalence of certain foods, such as sugar, can make an elimination diet difficult, and you should not take a food reaction solely into your own hands. If you suspect a food sensitivity or allergy is the cause of your congestion, consult your doctor or nutritionist for help planning a diet around your condition.
References
- MayoClinic.com; Wheat Allergy; July 2011
- "Sun Sentinel"; Myth Busting: Does Drinking Milk Lead to Congestion?; Anahad O'Connor; April 2010
- Auckland Allergy Clinic: Alcohol Intolerance (Adverse Effect to Alcoholic Beverages)
- CFIDS Association of America: Treatment: Elimination Diet
- VAXA: Children's Food Alergies
