This article was medically reviewed by Natalie Butler, RDN, LD.

Did you know that your stomach contains more than 100 trillion bacteria cells? Some of them are your friends, while others are working against you. These nasty bacteria thrive on sugar and other dietary and lifestyle choices reduce healthy bacteria which encourages the growth of unhealthy bacteria.

So, within you is a bacteria war constantly being waged. Your good bacteria are valiantly trying to protect you from the negative effects of bad bacteria and keep your intestinal lining healthy. When you take probiotics you are boosting your good bacteria to help overcome the enemy and ensure that your immune system is working at peak efficiency. 

The standard American diet contains a lot of processed foods that are packed with sugar, additives like emulsifiers and proteins that can weaken intestinal permeability and gut bacteria. This is, of course, feeding the pathogenic bad bacteria in the digestive system. This sets the stage for a whole host of health problems, including obesity, diabetes, depression, and heart disease. It also suppresses our immunity, making us susceptible to the common cold and any other virus that happens to be floating around. 

Fermented foods which are rich in probiotics are the ideal food to boost your own internal probiotics. These foods also contain vitamins, minerals, polyphenols, antioxidants and may also contain prebiotic in fiber, the main bacteria to help your healthy gut bacteria thrive. 

Taking in the right natural foods will help to support your good bacteria. Examples of fermented foods are listed below:

• Kimchee
• Sauerkraut
• Fermented carrots
• Fermented zucchini and other vegetables
• Apple cider vinegar
• Kombucha
• Fermented garlic
• Yogurt
• Buttermilk
• Kefir
• Water kefir

Prebiotics

Prebiotics are foods rich in fiber that selectively feed your probiotics. A diet rich in prebiotics will help increase healthy gut bacteria which in turn will affect long-term health. Examples of these foods include:

• Green bananas
• Jerusalem artichoke
• Garlic
• Onions
• Leeks
• Asparagus
• Apples
• Oats
• Chicory root
• Inulin
• Resistant starches (starches that have been cooked, then cooled to refrigerator temperatures for at least 4 hours, then eaten. Reheating after the cooling process does not reduce the resistant starch amounts)

Health Benefits 

Balancing Gut Bacteria

Ideally, of the 100 trillion bacteria cells in your gut, the majority of them should be good bacteria. In most people, it is nowhere near that. That’s because of poor dietary choices, illness, antibiotics, stress and a host of other lifestyle factors.[source] 

Not having the correct ratio between good and bad bacteria in your gut can lead to such problems, such as digestive issues, obesity and cognitive impairment.[source]

Including probiotics in your diet, either in fermented foods or as stand-alone supplements is the best way to rebalance your gut bacteria.

They way to increase that number is by feeding your good bacteria with what it needs to thrive. Fermented foods, such as sauerkraut, kombucha, yogurt and other naturally fermented foods that create their own lactic acid bacteria are fantastic foods to increase your levels of healthy gut bacteria. 

Preventing Diarrhea

One particularly nasty side effect having an imbalance of gut bacteria is diarrhea. People who take antibiotics often experience diarrhea due to the antibiotics’ effect on gut bacteria balance. A number of studies have shown that a probiotic-rich diet can help prevent and even treat antibiotic-associated diarrhea.

Other research has shown that probiotics also may reduce the duration of non-antibiotic associated diarrhea such as those associated with H.pylori treatment.[source]

In addition, healthy gut flora improves the gut barrier function and intestinal permeability. Abnormalities in intestinal permeability are associated with digestive diseases, allergic reactions, digestive symptoms, autoimmune disease and other health conditions. [source]

Improving Mental Health

Surprising as it may seem, there are a number of studies that link the health of your gut bacteria with the functioning of your brain and mood.[source] These studies indicate that supplementing with probiotics may play a vital role in mental health.

A 2016 meta-analysis of 15 studies found that supplementation with the probiotics Bifidobacterium and Lactobacillus for up to eight weeks resulted in significant improvement in such conditions as depression, anxiety and obsessive-compulsive disorder (OCD).[source]

In another study, people who were diagnosed with major depressive disorder and who took a probiotic supplement consisting of 6 billion CFUs of Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium bifidum for 8 weeks greatly improved their depression, as well as their levels of C-reactive protein, which is a key marker for inflammation.[source]

Improving Heart Health

Specific strains of probiotics have been seen to improve heart health by reducing LDL (bad) cholesterol levels and bringing down blood pressure.

A 2000 review of five studies showed that a daily serving of probiotic yogurt over periods ranging from two and eight weeks reduced total cholesterol levels by an average of 4 percent and LDL cholesterol by an average of 5 percent.[source]

Other studies have focused on the ability of probiotics to help bring down blood pressure. A 2014 meta-study looked at nine studies and found that probiotics brought about a modest reduction in blood pressure. Greater improvements may be obtained in those with existing high blood pressure at baseline, when consuming probiotics at amounts greater than 100 billion CFUs per day, and/or for longer than 8 weeks.[source]

Reduce Allergies

A number of strains of probiotics have been shown to help reduce eczema symptoms in children and infants. Milk that was supplemented with the probiotics Bifidobacterium lactis and Lactobacillus rhamnosus GG was found to significantly improve eczema symptoms in infants compared with unsupplemented milk.[source]

In another study, which tracked the progress of infants whose allergic mothers took probiotics during the last 2 months of pregnancy and while breastfeeding, revealed that their babies were 83 percent less likely to get eczema in the first two years of life.[source]

Boost Immune System

Probiotics have been shown in a number of studies to improve the body’s immunity. A number of probiotics have actually been seen to boost the production of natural antibodies, immune cells, and inactivate viral particles.[source]

A 2001 study, which involved 570 children, showed that the probiotic Lactobacillus GG reduced respiratory infection in children in daycare settings by 17 percent.[source]

Symptoms of Imbalanced Gut Bacteria

Imbalanced gut bacteria is also known as dysbiosis which, according to the International Journal of Molecular Sciences, may result or be associated with the following conditions or symptoms [source]:

• Digestive symptoms such as bloating, diarrhea and constipation
• Digestive disease
• Diabetes
• Food allergies
• Lack of energy
• Obesity
• Skin problems
• Chronic respiratory infections
• Cancer

Conclusion

The health of your gut bacteria is highly influenced by your diet and lifestyle. Make sure that you are getting enough sleep, managing stress and avoiding antibiotic use when possible. It is while you are sleeping that the gut repairs itself. Get out in nature regularly in order to soak up plenty of Vitamin D. Flexibility and exercise are also important. Eating a balanced whole food, plant-heavy diet, rich in fiber and fermented foods, is essential.

If you are unable to get a good range of plant-based foods in your diet, suffering from a disease or chronic symptoms, or are taking antibiotics, look out for a quality, multi-strain probiotic supplement. Recommended dosages vary but range from 40 to 120 billion CFUs per day for most conditions. Fiber supplements containing prebiotics like chicory root or inulin will feed your good bacteria and help to bring about the ratio of bacteria that will ensure that your immune system is working at its best.