This week we will examine how good dietary habits and optimal nutrition can enhance immunity. We will also look at how poor dietary and nutritional choices drain your energy and inhibit your immune system.

Even though I generally do not believe in calorie-counting it is very important to discuss caloric intake. Your immune system runs on energy derived from your diet. If you consume too few calories the immune system will not have the energy to operate effectively. If you consume too many calories not only will immunity be decreased but weight gain and fat deposition can become an issue.

Photo: Contributed - (Flickr user, jaxxon)

It is important to understand the difference between nutrient-dense foods and calorie-dense foods. Nutrient-dense foods are high in vitamins, minerals, and other essential nutrients per calorie they provide. Whereas, calorie-dense foods are very low in nutrients per calorie provided. Focus your diet on nutrient-dense foods like vegetables, fruits, legumes, whole grains, nuts, and seeds. Limit your consumption of calorie-dense foods like sugary treats, pop, white bread, white pasta, and other refined foods. Consuming mostly nutrient-dense foods is a great way to provide your immune system with all of the calories and essential nutrients it requires.

The type of carbohydrates you consume has a direct effect on the integrity of the immune system. Simple and refined carbohydrates contain sugars that are released into the blood stream relatively quickly. They increase blood sugar levels rapidly, causing the hyper-release of insulin, which ultimately leads to low blood sugar levels. This will not only wreck havoc on your energy levels throughout the day but also inhibit immunity. Sugar directly inhibits the action of white blood cells and leads to decreased immunity. Focus your carbohydrate consumption on complex carbohydrates because they take longer to digest and release sugar into the bloodstream more gradually and sustainably.

Proteins are the building blocks for all of the structures in the physical body. The immune system is no exception. All immune cells like the various white blood cells are composed largely of protein. Protein deficiency leads to decreased immunity. Therefore, ensure you are consuming optimal amounts of protein in your diet. Typically, 20-30% of your caloric intake should be from lean sources of protein like cold water fish, organic eggs, chicken, beef, wild game, beans, legumes, and whey, rice, hemp, or soy protein powders. Avoid unhealthy proteins like deep fried meats, cured meats, and protein powders with artificial flavours, colours, and additives.

We have all heard of the importance of essential fatty acids for cardiovascular disease and brain health. However, essential fatty acids and other healthy fats are also integral for immune system function. Membranes of all cells are composed of fats, proteins, and some carbohydrates. It is the fats of the membrane that determine how flexible the cell is and how well signals are transported to and from cells. A diet high in saturated, oxidized, or hydrogenated fats leads to inflexible cell membranes of all cells of the body including immune cells. Consuming essential fatty acids and other healthy lipids from cold water fish, flax, hemp, raw nuts, raw seeds, olive oil, and coconut oil promotes healthy cell membranes and thus healthier immune cells.

Digestion and absorption is as important as the food you consume. Many people come to see me with relatively healthy food intake but unfortunately they have difficulty getting the nutrients into the cells of their body. Gas, bloating, abdominal pain, acid reflux, loose stools, diarrhea, constipation, brittle nails, dry skin, and rectal itching are all signs of compromised digestion and absorption. If you are experiencing any of these symptoms your immune system will not be able to function optimally for two reasons. First of all, your cells won’t get the optimal levels of the essential nutrients they require. Secondly, the immune cells that line your GI tract may be hyper-activated and thus drawing resources away from other areas.

Good nutrition, digestion, and absorption can do a lot to improve the function of your immune system. If you suffer from frequent colds, flu’s, or other infections you may be able to strengthen you immune system and have a healthier winter this year by improving your nutrition and supporting your digestive system.