Living Columns & Blogs

Healthy gut bacteria improve immunity

The human body contains 10 times more bacteria than cells. These bacteria live on the skin, in the mouth, in the intestines and many other parts of the body. Many people turn to hand sanitizer; however, too much sanitizer can be part of the problem when it comes to not forming a strong immune system. Studies have shown that no matter how much hand sanitizer people use, their bodies are filled with bacteria and other microbes — and that’s a good thing.

The helpful bacteria, viruses, protozoa and fungi that live in the body make up the microbiome. These diverse microbes help us digest food, protect us against disease-causing bacteria and make vitamins such as B12, thiamin and riboflavin. Changes in the microbiome — resulting in too many bad bacteria and not enough good ones — can make it more difficult for the body to drive away illness.

An imbalance in the microbiome can impact the development of a wide variety of ailments, including:

▪ Diabetes

▪ Rheumatoid arthritis

▪ Multiple sclerosis

▪ Fibromyalgia

▪ Irritable bowel syndrome

▪ Obesity

▪ Cancer (certain diagnoses)

▪ Depression

Researchers are still trying to figure out exactly how the microbiome helps the body stay healthy. For example, colon cancer appears to result from the relationship among the microbiome, the immune system and the cells that line the colon.

Growing a healthy microbiome

The development of a healthy microbiome starts before a baby is born. A pregnant woman’s diet impacts her microbiome, which she will pass on to her baby. During a traditional vaginal delivery, an infant’s microbiome is colonized with the mother’s bacteria. Nursing mothers who eat a good diet continue to pass on a strong biome to their infants through breast milk. Babies who are born via cesarean section and those who are solely formula-fed lose some of these advantages for lifelong protection from disease but can still develop healthy microbiomes with proper diet choices.

The makeup of an individual’s microbiome varies with the person’s genetics, age, ethnicity and exposure to chemicals, but the No. 1 impact on the microbiome is diet. After thousands of years of a relatively stable diet, Americans in recent decades underwent a dramatic shift to a Western diet that is high in animal-based fats, refined sugars, preservatives and other chemicals, and low in fiber and diversity. This shift has resulted in an increase in gut disease. Overuse of antibiotics is another major cause of damage to the gut biome, since antibiotics kill both bad and good bacteria.

Re-establishing a healthy population of good bacteria in the body takes time. Start with one small change to your diet, and add more healthy changes with each success. Follow these general guidelines:

▪ Eat plenty of fruits and vegetables.

▪ Limit processed foods that are not found in nature.

▪ Consume at least 25 grams of fiber each day (most Americans get only 10 grams).

▪ Consider adding probiotics to the diet, preferably through natural foods rather than supplements.

Benefits of probiotics

Probiotics are what should be in the gut — remember good bacteria should exist in your body. They can be found in foods and drinks such as yogurts labeled as containing “live and active cultures” and other dairy products that contain probiotics like lactobacillus or kefir. Fermented vegetables, such as sauerkraut and kimchi are also sources of probiotics, as long as they are not heated before serving.

Recently, kombucha tea has become popular in the United States for its probiotic benefits. Kombucha is a fermented drink made with tea, sugar, bacteria and yeast and has been a traditional drink in some Asian cultures for centuries. Raw or unpasteurized kombucha is rich in probiotics. Kombucha also has high levels of antioxidants and iron and is believed to increase energy production in cells, limit fat storage, lower cholesterol and reduce fatty liver disease.

As with just about any substance, it’s best to consume kombucha in moderation and to be sure that homemade kombucha was brewed in sanitary conditions.

Remember that diet can improve or damage the microbiome that lives within every person. A varied diet with lots of plant-based foods and limited processed foods plus added probiotics can improve the microbiome and overall physical and mental health.

Barbara H. Cole, MS, CRNP, is a nurse practitioner with Penn State Medical Group.