Yogurt appears to boost the immune system, reducing allergy symptoms and lowering the incidence of upper respiratory infections. In one long-term study, young adults and seniors consumed a serving of 200 grams of yogurt each day for one year. One group received yogurt containing active cultures and others received pasteurized yogurt or none at all. After one year, both yogurt groups experienced fewer allergy symptoms. This effect was greater in the group consuming active cultures. Respiratory illnesses, such as colds and flu, were also lower in the yogurt groups.
How It Works
The exact mechanism by which yogurt improves immune system function is not known. However, several studies have provided some clues. The lactobacteria in yogurt stimulate the production of immunoglobulin A, the primary immune system molecule that protects your body from foreign pathogens that enter orally. Researchers at the University of Vienna have found that yogurt causes white blood cells to produce higher levels of cytokines. These are small molecules that mediate the immune system response.
Other Health Benefits
In addition to its positive effects on the immune system, yogurt has been associated with other health benefits. The live cultures in yogurt produce lactase, the enzyme that is deficient in people with lactose intolerance. Yogurt is easily digested and improves the absorption of calcium and B-vitamin. The active cultures in yogurt support the growth of beneficial bacteria in the intestines and help to repopulate those bacteria after illness or antibiotic treatment. Regular yogurt consumption reduces LDL and total cholesterol.
When selecting a a type of yogurt form the many available brands, look for those low in sugar and added fillers. High quality yogurts will contain only a few ingredients, primarily milk and active cultures. The yogurt used to coat snack foods, such as pretzels or raisins, is high in sugar and does not provide health benefits. Both conventional and active culture yogurts have been associated with improvements in allergy symptoms. However, yogurts that contain active cultures also provide many additional health benefits, especially for digestive health.