What We Learned and What You Should Know: Nutrition and Immunity

Lady taking a selfie while working at Kellogg Conference Center

The Bottom-Line

What you eat today, impacts your immunity tomorrow (well, many tomorrows from now). And don’t count on supplement powders, pills, drinks, or gummies to give your immunity a boost.

More Details

Our immune system is our body’s active defense against pathogens. Its job is to recognize harmful intruders, work to remove them, and keep a memory so if the same intruder returns, it can be better at eliminating it. Immune cells come from precursors in bone marrow and develop into mature cells. They are found all over the body, including, skin, bone marrow, bloodstream, thymus, lymphatic system, lymph nodes, spleen, and mucosal tissues. Specialized immune hubs are found in mucosal tissue in the small intestine that work with the gut’s microbiota. It’s no wonder why it is so important to eat plenty of fiber-filled, prebiotic-rich plants to keep the gut healthy and maintain a ship-shape immune system.

The foods we eat provide our body with nutrients - the building blocks of immune cells. Nutrients also regulate our body’s cellular response to build more immune cells as they’re needed. Therefore, nutrient inadequacy hinders our immune function. Consuming adequate amounts of the necessary nutrients to support immune function is a long-term game: fill your plate with more fruits, vegetables, whole grains, fish, beans, seeds, nuts, and spices year-round, not just during “cold season”. Eat an orange, red bell peppers, or strawberries every week to maintain vitamin C status, not just when you have the sniffles.

A weakened immune system and slowed immune response are part of the natural aging process. Obesity contributes to a similar reduced immune function as seen with aging (referred to as “accelerated aging”). While we can’t do anything about aging, we can do quite a lot to maintain a healthy weight or lose excess weight – in turn reducing our risk or the progression of obesity, respectively. The right food choices promote immune function and a healthy weight pattern.

Take Action

Support your immune system with a healthy diet, adequate sleep, and daily exercise. Assess your overall meal patterns. Are there any areas for improvement? Are you getting your 5-7 servings of colorful fruits and vegetables each day? While that may sound like a lot, most servings are just ½ cup. Are you eating enough calories? An extremely low-calorie diet makes it difficult to meet nutrient needs, and nutrient deficiencies may suppress the immune system. Are you staying hydrated? Aim for 6-8 cups a day and observe your urine color to gauge hydration status throughout the day. Are you eating enough fiber? Aim for 25-30 grams per day, preferably from natural food sources like whole grains, fruits, vegetables, and legumes, to keep your gut in good shape.