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Should I Take a Probiotic?

Updated: Dec 3, 2022

Digestive health complaints are on the rise! You may be wondering if a probiotic supplement can be helpful. If it is, how do you pick the right one?

Image of healthy digestive tract without leaky gut

Nearly 61 percent of Americans report negative GI symptoms, according to a study including over 71,000 people. The most common symptoms include heartburn/reflux, abdominal pain, bloating, diarrhea, and constipation. While this should be a surprising statistic, considering what the average American eats (or doesn't eat), it is not surprising so many have digestive health problems.

The Standard American Diet, better known as the SAD diet, is low in fiber, fruit, and vegetables, and high in saturated fat and processed foods. This has a negative impact on the gut environment. Add in a lack of exercise, too much stress, and regular alcohol've got a recipe for gut dysfunction.

The good news is that digestive health can improve through proper food choices, supplementation when necessary, and a healthy lifestyle including regular exercise, stress management, and quality sleep. A probiotic is not a quick fix for all GI problems, but it can be an important piece of the solution.

What are Probiotics?

The word "probiotic" means "for life" in the Greek language. We have over 100 trillion microbes living naturally in the gut. There is a delicate balance of both good and bad microbes that exist in harmony. A probiotic is defined as a microbial cell that is potentially healthful to the host (i.e., human body in this case) and therefore part of the "good" microbe community.

Health Benefits of Probiotics

According to research to date, probiotics have been found to play a beneficial role in many health conditions and provide a variety of health benefits, including the following:

  • Improve immune system function

  • Improve digestive function

  • Reduce symptoms of Irritable Bowel Syndrome (IBS)

  • gas, bloating, diarrhea, constipation, abdominal pain

  • Reduce symptoms of Inflammatory Bowel Disease (IBD) (Crohn's disease and ulcerative colitis)

  • Reduce gut microbial imbalances:

  • small intestinal bacterial overgrowth (SIBO), candida overgrowth or pathogen overgrowth

  • Promote repair of gut lining damage (i.e., leaky gut syndrome, or increased intestinal permeability)

  • Reduce risk of colon cancer

  • Manage and reduce cholesterol levels

  • Improve symptoms of depression and anxiety

Preliminary research indicates that probiotics may play a role in benefitting the following conditions:

  • Hormone imbalance (PCOS, endometriosis, thyroid balance)

  • Autoimmune conditions (rheumatoid arthritis, multiple sclerosis, Type 1 diabetes)

  • Cognitive impairment (memory, focus)

  • Blood sugar imbalance

  • Allergies

  • Skin conditions (acne, eczema, psoriasis)

  • Sleep dysfunction

Choosing the Right Probiotic

Probiotic microbes include mainly bacteria but also include certain yeasts. They are naturally present in fermented foods, may be added to certain food products, and are available as dietary supplements.

If you know you have gut health imbalances, then starting with a probiotic supplement for a few months and then transitioning to food sources of probiotics may be a good approach. Starting with a probiotic supplement will allow you to choose the specific species and strain that may provide the desired health outcome, based on scientific evidence.

The probiotic supplement you take matters in terms of expected health outcome!

There are many different types of probiotics, which are identified by their specific strain. Every strain includes the genus, the species (and subspecies for certain strains), and an alphanumeric strain classification. Some of the most commonly used genera of microbes in probiotic products include Lactobacillus, Bifidobacterium, Bacillus, Saccharomyces, and Streptococcus. An example of a probiotic would be Bifidobacterium longum 35624, where "Bifidobacterium" is the genus, "longum" is the species, and "35624" is the strain.

It may seem obvious that Lactobacillus acidophilus is different than Bifidobacterium bifidum because their names are different. But the average consumer may not know that the different strains have different health effects!

Those looking to use a probiotic supplement for a targeted health benefit should base their choice on published scientific evidence showing which probiotic species, strains, and doses may benefit their specific health condition.

A growing number of studies have shown that various probiotic strains have different biological effects in the body. For example, certain strains are known to support neurotransmitter production, including the hormone serotonin which supports good mood. Other strains may help reduce symptoms of IBS and support repair of the gut lining (i.e., leaky gut).

The WGO (World Gastroenterology Organisation) indicates that the optimal dose of probiotics depends on the strain and product. They also recommend that clinicians who advise their patients to use probiotics specify the probiotic strains, doses, and duration of use that studies in humans have shown to be beneficial.

Tips in Choosing a Probiotic Supplement

Quality and strain choice matter! Choose a manufacturer that invests in quality control and formulation based on scientific research. Here are some specific guidelines to look for in the manufacturer of the product you choose:

  • Follows Good Manufacturing Practices (GMPs) - a system for ensuring that dietary supplements are consistently produced and controlled according to quality standards established in the United States.

  • Uses Independent Laboratory Analysis - probiotic ingredients and final products should be analyzed by an independent laboratory for quality and potency.

  • Checks Genetic Identity of Probiotic Strains - this ensures that the specific probiotic strains listed on the label are actually in the product, and that harmful strains are not in the product.

  • Validates Potency - the manufacturer should store and ship the probiotic under temperature and climate conditions to maintain potency of probiotic ingredients. Beware of purchasing a probiotic that is not stored or shipped in cool/dry conditions, such as what may occur with online warehouse distributors.

  • Free of Allergens and Other Irritating Ingredients - high quality manufacturers will ensure their probiotic supplement is free from common allergens (wheat, gluten, milk/casein, eggs, fish, shellfish, peanuts/tree nuts, and soy) as well as artificial ingredients or preservatives.

For General Health or Digestive Support - look for a high quality, broad spectrum probiotic with the following beneficial strains:

  • Lactobacillus rhamnosus

  • Bifidobacterium bifidum

  • Lactobacillus acidophilus

  • Lactobacillus casei

  • Lactobacillus plantarum

  • Lactobacillus salivarius

  • Bifidobacterium longum

  • Streptococcus thermophilus

  • Lactobacillus bulgaricus

  • Lactobacillus paracasei

  • Bifidobacterium lactis

  • Bifidobacterium breve

For improving symptoms of leaky gut syndrome (i.e., increased intestinal permeability) - look for a broad-spectrum spore-based probiotic with the following strains:

  • Bacillus indicus, HU36™

  • Bacillus subtilis, HU58™

  • Bacillus coagulans (SC-208)

  • Bacillus licheniformis

  • Bacillus clausii (SC-109)

(Once symptoms of leaky gut have been resolved, then transitioning to a general broad-spectrum probiotic or food sources of probiotics may be a good option).

Food Sources of Probiotics

Dietary sources of probiotics are a good addition to a healthy lifestyle. Some of the foods that are richest in probiotics include yogurt, kefir, sauerkraut (or other fermented vegetables), kimchi (Korean side dish of fermented cabbage), and miso (Japanese fermented soybeans used in sauces or soups).

The probiotic amount and strain will vary among these foods and different brands. Therefore, a probiotic supplement taken at an effective dosage for several months may be beneficial for helping with a specific health concern. Once the health issue has been resolved, then probiotic-rich foods may help maintain a healthy gut environment when combined with a gut-friendly lifestyle including whole foods, regular exercise, quality sleep, and good stress management.

The Bottom Line

Most people can benefit from taking a high-quality probiotic supplement based on data regarding the nutritional inadequacy of the American diet and high percentage of people with digestive health problems. In addition, probiotic supplements are considered safe and may help maintain healthy microbial balance benefiting many aspects of health beyond digestion.

When choosing a probiotic supplement, quality and choice of strains matter the most. Choose a brand by visiting the company's website to see if they invest in high quality standards and evidence-based research in product development. Those who have tried a basic probiotic from the grocery store and have not found benefit may consider trying a professional grade probiotic which may be more targeted towards their health concern. Professional grade supplements may be purchased through your Registered Dietitian Nutritionist or nutrition-focused health care professional.

If you need help with selecting the right probiotic or other supplements, and incorporating diet and lifestyle strategies to improve gut health problems, consult a Registered Dietitian Nutritionist (RDN) who specializes in digestive health. You may also book an Introductory Call with Kirkman Nutrition to see if my program/services can help you.


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