Factors like emotional stress, smoking (including secondhand smoke), environmental pollution, insufficient sleep, and lack of exercise all undermine immune function. These elements increase free radical production, accelerate nutrient depletion, weaken immune cell activity, and inhibit nutrient absorption.
Excessive Fat
Certain fats increase free radical production (e.g., excessive unsaturated fatty acids), others accelerate nutrient depletion (e.g., refined sugars, alcohol, caffeine, medications), some weaken immune cell function, and others inhibit nutrient absorption (e.g., alcohol and certain drugs). Fried foods, snacks, and carbonated beverages should be avoided.
Balanced Diet, No Food Restrictions
Obtaining ample nutrition from natural, fresh foods may seem obvious, yet it remains the dietary secret to maintaining immune function. Prioritizing whole grains, ample vegetables and fruits, soy products, and moderate amounts of dairy, eggs, fish, and meat ensures comprehensive nutritional intake.
Foods like buttermilk, cruciferous vegetables, bitter melon, garlic, onions, and shiitake mushrooms are also believed to boost immunity due to their rich content of non-nutrient substances beneficial to the body. Some books and studies recommend vegetarian diets, but the prerequisite remains understanding how to obtain balanced nutrition from plant-based sources.