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Digestive Immunity: Immune system directly related to Diet and Supplements

Digestion | July 30, 2014 | Author: The Super Pharmacist


Digestive Immunity: Immune system directly related to Diet and Supplements

Research now shows that the average Western diet can actually weaken the body's immune system. An impaired digestive system can result in a variety of symptoms such as gas, bloating, diarrhoea, constipation, reflux, abdominal pain, nausea, food allergies, celiac disease, colitis, and irritable bowel syndrome. Symptoms of compromised digestion may also result in many disorders often not immediately linked to digestion such as seasonal and environmental allergies, sensitivities to molds, rashes, eczema, fatigue, weakness, headaches, yeast infections, chronic colds, chronic fatigue syndrome, and many autoimmune disorders.

What is Digestive Immunity?

It is believed that 80% of all immune functions actually come from the digestive system. The healthy small intestine contains a number of defense mechanisms. The small intestine is rather like a skin inside the body, designed to protect the human being from pathogens.

What is Digestive Immunity?A layer of mucus lines the inner wall of the intestinal tract and acts to support friendly bacteria (probiotics). Within the folds of the intestinal wall itself, abundant numbers of lymph glands guard against bacteria, viruses and other pathogens. This local immune system is called gut-associated lymphoid tissue (GALT), and it is the largest lymph system in the human body. Thus, of all the internal organs, the digestive tract appears to exert the most profound influence on the body's overall immunity.

What Factors Impair Digestive Immunity?

Too much sugar, Too much fat

On the average, Australians consume 100 pounds of sugar per year. Studies show that a bad sugar habit can cause mood swings, personality changes, enhance nervous disorders, cause diabetes, and accelerate the development of heart disease.

In Western countries, fat usually contributes 35–45% of the total energy intake although some individuals may eat less, and some more, than this. Changes in total fat intake can influence the immune response in humans.

Excessive Alcohol

Alcohol, like sugar, does not provide any additional nutrients, which can lead to nutrient deficiency. Excessive alcohol reduces the ability of white blood cells to kill germs.


When it comes to the immune system, smoking causes more risk for influenza and pneumonia.

Smokers also take more time to recover from an illness because it represses the ability of the immune system to function properly.


Studies have shown that taking a course of antibiotics leaves the intestine virtually bare of beneficial bacteria. Many people will get a yeast infection following a course of antibiotics. Women frequently get a vaginal yeast infection after a course of oral antibiotics. Another condition, especially dangerous for some people who receive antibiotics, is the growth of another bacteria, Clostridium difficile.


Chlorine in drinking water decreases beneficial bacteria in the intestine. Concentrated chlorine, as in a swimming pool, kills all bacteria.


The digestive system needs the body to be relaxed in order to secrete the important digestive acids and enzymes needed to break down food for proper absorption. Eating on the run or while working does not allow the body to relax and the digestive process is dramatically hampered.

Non-steroidal anti-Inflammatory drugs (NSAIDs)

In addition to reducing fever, inflammation and pain, the NSAIDs markedly reduce the ability of the intestinal cells to produce mucus which normally lines the inner walls of the intestines and contributes to digestive immunity.

Nutritional deficiencies

Deficiencies in vitamins, carotenoids and trace minerals can impair the immune response.

What Factors Can Improve Digestive Immunity?


An excellent way to boost digestive immunity is by directly consuming probiotic bacteria, which are live bacteria food supplements that benefit the body by improving its intestinal microflora balance.

What Factors Can Improve Digestive Immunity?By introducing these specific bacteria into our diets, we can support our body's natural defence barrier against disease and promote optimal health.

Probiotics positively influence both gut-associated lymphoid tissue (GALT) tissue and microfloral balance in the intestines. 

Naturally fermented probiotic foods and liquids contain the necessary good bacteria to rebuild the microflora. They are predigested so that the body can absorb the nutrients more easily.

  • Probiotic foods include: unsweetened plain yogurt, kefir, cultured vegetables, kombucha, beet kvass and naturally fermented probiotic liquids. 
  • Supplementing with high-quality acidophilus, bifidus and other friendly bacteria has been shown to increase immunity not only in the intestine but also through the whole body. Recent studies have shown a benefit in treating irritable bowel syndrome and inflammatory bowel conditions like Crohn's and ulcerative colitis with daily probiotics.

Blue-green algae

Food which is organically farmed contains a much wider range of micronutients which the body can use to support overall health. One of the family of foods richest in mineral micronutients is known collectively as blue-green algae. This family of edible algae comes from three different sources:

  • Spirulina: This is a spiral shaped blue-green algae growing in Japan and Hawaii.
  • Chlorella: Chlorella is another farmed algae mostly from Hawaii which has a tough outer shell which needs to be ruptured prior to eating.
  • Aphanizomenon flos-aquae (AFA): This thrives, pure and contaminant-free, nourished by the volcanic sediment rich water, in the mountains of Oregon.

All these algae are fine sources of mineral micronutients as well as being rich in omega-3 fatty acids, chlorophyll and a blue pigment, phycocyanin. Phycocyanin has been linked to a number of health benefits including enhanced immunity. Additional research is necessary to substantiate these reported health benefits of blue-green algae.

Healthy fatsHealthy fats

The body needs an adequate amount of healthy fats to help absorb fat-soluble nutrients and to maintain good overall health and a healthy immune system.

Healthy fats are contained in monounsaturated and polyunsaturated oils and foods like fatty fish, olives, nuts and avocados.

Whole grains

Whole grains are rich in fibre, vitamins, minerals and hundreds of phytochemicals. They contain several substances including fibre (both soluble and insoluble), antioxidants, phenols and phytoestrogens that have each been linked to lower cancer risk.


Although L-glutamine is synthesised in the body, the introduction of external sources of L-glutamine can bring its own benefits. During times of stress, glutamine levels in the body can become low as more demands are made upon this amino acid. Factors such as stress, aging, serious illness, infection and surgery can cause glutamine to be drawn away from muscles, where the majority of it is stored, to help the immune system or to regulate blood sugar. Under these circumstances, where glutamine levels are low, glutamine can be a conditionally essential nutrient.


Eating foods that are rich in antioxidants—including vitamins E and C, carotenoids and selenium—may bolster the body's immune system. According to studies, however, taking supplemental antioxidant pills likely has little benefit. The current American Heart Association guidelines recommend including these nutrients in the diet, but supplements are not recommended. The most antioxidant-rich foods are from the plant kingdom, including fruits, vegetables, whole grains, nuts and seeds.


Selenium is essential for a strong immune response. Studies suggest that very ill people or those with compromised immune systems can benefit from additional selenium; however, otherwise healthy people are not likely to need extra doses.

The mineral, found mostly in mushrooms, whole grains and most famously Brazil nuts, may also reduce the risk of some cancers. The best food sources of selenium are seafood: tuna, red snapper, lobster and shrimp. Other good food sources of this mineral include chicken (white meat), whole grains, brown rice, egg yolks, cottage cheese, sunflower seeds, garlic, Brazil nuts and lamb chops.

Vitamin E

Vitamin E is especially important for immune function. Wheat germ oil, sunflower seeds and sunflower oil, almonds, safflower oil and hazelnuts are all excellent sources of vitamin E. Vitamin E supplements are no longer recommended based on the lack of studies to show benefits. Too much vitamin E can also have unintended health consequences, including an increased risk of bleeding and impaired blood clotting.


Zinc is another mineral important to a healthy immune system, and people who are deficient tend have a poorer immune response. Zinc is needed to produce and activate some types of white blood cells that help fight infections, and studies show that when zinc-deficient people are given zinc supplements, their immune functioning improves. Zinc has long been promoted as a nutrient that can lower the severity and incidence of the common cold, but clinical trials with the mineral have yielded inconsistent results. Too much supplemental zinc (more than 75 milligrams per day) can actually inhibit immune function, and larger doses can be toxic. Therefore, it is best to rely on dietary sources of zinc. Zinc-rich foods include oysters, vitamin and mineral-fortified cereals, crab, beef, dark-meat turkey and beans.


The current consensus is that eating plenty of beta carotene-rich foods is safe and beneficial to overall health and maybe immunity, but taking a large-dose supplement of either beta-carotene or vitamin A is not recommended and may even be harmful. There are numerous delicious food sources of beta-carotene including oranges, papayas, tangerines and peaches, as well as red peppers, sweet potatoes and carrots.


Beta-glucans are simple, highly purified, complex carbohydrates, derived from food grade baker's yeast. Beta-glucans are types of fibre found in the cells of certain yeast, algae, bacteria, and fungi. They are also found in certain plants, such as oats and barley. Many health researchers consider beta-glucans to have effective immunity enhancing substances.

Enzyme supplements

Enzymes are secreted by the digestive organs to accelerate the breakdown of food (carbohydrates, proteins, and fats) so that nutrients can be extracted and absorbed. Taking supplemental enzymes, especially when eating foods that are highly processed, cooked improperly or difficult to digest, reduces stress to the digestive system and supports the proper uptake of nutrients. 

The decreased supply of digestive enzymes that occurs naturally with aging also reduces the absorption of available nutrients. Enzyme supplements are produced from plants, fungi, bacteria, and animal sources, and are available in a variety of forms. There are enzymes that digest carbohydrates, fats, proteins, and fibre. Other enzymes are formulated to assist the digestion of problem substances like gluten and lactose. Australia's best online pharmacy


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