What You Need to Know About Probiotics in Your Diet

Having a healthy gut with the right balance of good bacteria may change the entire health of our bodies.

Who knew bacteria could actually be a good thing? The business of beneficial bacteria is booming and the word “probiotic” has landed on everything from yogurt and kefir to kombucha and kimchi.

What are they? They are amazing, live microorganisms called probiotics, also fondly referred to as “friendly bacteria.”

Having a healthy gut with the right balance of good bacteria may change the entire health of our bodies. Probiotics have generally been tested in humans and shown to result in a health benefit when consumed in specific amounts for a particular probiotic strain.

You can’t generalize when it comes to probiotics

Different strains of probiotics are known to provide different benefits. The health benefits of 1 probiotic strain should not be generalized to other strains without confirmation from separate studies. When reading these studies, keep in mind that the clinical trial results from 1 probiotic strain in 1 population cannot be generalized to other probiotic strains or to different population groups. Many probiotics experts suggest using probiotics from companies that have research and data supporting the use of that particular strain.

Probiotics work their magic in both the small and large intestine

Different probiotics do different things in different parts of our GI tract. In the small intestine, research suggests that certain probiotics may give some aspects of our immune system a boost. In the large intestine, certain probiotics can work in several ways: some prevent harmful bacteria from attaching to the intestinal wall preventing growth, while others improve the balance and functioning of the natural microflora within the intestinal lining.

What might cause an imbalance of good and bad bacteria?

Normally our bodies have a healthy ratio of bacteria, but certain health conditions and/or lifestyle factors can create an imbalance that can favor the growth of disease-causing bacteria. The most common cause of bacteria imbalance in adults is thought to be the inappropriate use of antibiotics. Some other potential causes may include:

  • Broad-spectrum antibiotics
  • Gastrointestinal infections
  • Gastrointestinal surgery
  • Acid suppressors (PPIs)
  • Chronic maldigestion
  • Chronic constipation
  • Chronic psychological stress
  • Standard American diet
  • Gluten sensitivity/Celiac disease

Benefits of getting probiotics from food:

Benefits from a probiotic-containing food can be beneficial depending on the particular strain a product contains and whether research has demonstrated the beneficial effect. Two potential effects that would benefit most of us include boosting the immune system and encouraging a healthy balance of bacteria in the GI tract. Is there an added benefit to getting probiotics from our food?

Getting probiotics in dairy foods is an example of a win-win. Dairy foods help protect the probiotic bacteria as they travel through the digestive tract by providing a buffer to stomach acids, increasing the chance the probiotics survive and make it to the intestine. Fermented dairy products, like yogurt, are also a source of key nutrients, such as calcium, protein, and potassium.

Are Probiotics safe for everyone?

The good news is none of the studies have shown probiotics to be harmful in healthy people. Lactobacillus, Bifidobacterium, Saccharomyces and S. Thermophilius are the probiotic species that experts consider quite safe for healthy individuals. Probiotics may actually be harmful to those who have an acute illness, a compromised immune system, leaky bowel concerns (including pancreatitis), or those terminally ill with cancer. In this population, it may be beneficial to recommend a patient to their primary care provider before starting a probiotic.

Prebiotics + Probiotics are more effective

Just as plants need sun and water to grow, probiotics need prebiotics in order to thrive within your intestine. Prebiotics, or “good” bacteria promoters, are specific fibers that are indigestible in humans and found in plant foods. These fibers are fermented and used by the “good” bacteria but not by the “bad” bacteria.

Although more studies need to be done, experts believe prebiotics may also boost gut health by increasing the amount of Bifidobacteria, which is associated with inhibiting the growth of “bad” or pathogenic bacteria.

So where do we find these amazing prebiotics? There are a variety of plant foods that contain these compounds. Inulin is a well-studied prebiotic that you can find in garlic, onion, asparagus, leeks, chicory, jicama and Jerusalem artichokes. For other prebiotic fibers, enjoy bananas (particularly green bananas which are high in prebiotic-acting resistant starch), berries, ground flaxseed, chia, beans and legumes, whole grains (including whole wheat, oats and barley), dark leafy greens (especially dandelion greens) and unsweetened cocoa, just to name a few.

Prebiotic Tip: When adding fiber and prebiotic foods to your daily diet, do it gradually and always remember to drink more water than you usually do—this can help minimize any GI upset that can occur.

Elaine Magee, MPH, RD, is a Wellness Corporate Dietitian for Albertsons Companies and the author of 25 books including Tell Me What to Eat if I Have Irritable Bowel Syndrome.