A Study of Probiotics and their Correlation to Weight Loss and Health

As trendy as probiotics have become, they’ve actually been popular for centuries as people noticed that fermentation was not only a good way to preserve food, but that eating these fermented foods led to health benefits such as improved digestion.

Beginning around 1899, scientists started taking a closer look at why and how fermented foods work to keep us healthy. While we now understand the benefits of these foods comes from bacteria that alter human gut flora, the extent of these effects is still coming to light.. and the findings so far are pretty exciting.

What are Probiotics?

Probiotics are “good” bacteria that encourage the growth of other good bacteria in our guts. You may also see probiotics listed as “live cultures” especially on yogurt containers.

But why should we care about what kind of gut bacteria we have? As mentioned above, the gut microbiome is still being explored, but so far the research is showing that the types and variety of bacteria in our guts may effect everything from digestive regularity to chronic disease risk to mental health.

Why Is Everyone So Obsessed?

As alluded to above, research on probiotics is showing potential for management as well as prevention of disease. Current areas of study are varied, and include the role of probiotics on metabolic health, obesity, anxiety and depression, bone health, food allergies, irritable bowel disease and IBS, infant gut health, response to vaccinations, and immune function in the elderly.

While each one of these could have a post to itself, let’s just quickly take a look at what the research is finding on five of the more common potential health benefits.

1. Diarrhea: the role of probiotics in prevention and treatment of diarrhea is the most widely studied application of probiotics.

While antibiotics can play an important role in fighting bacterial illnesses, they can also negatively affect our guts by wiping out our natural bacteria, creating space for harmful bacteria to grow. As a result, individuals taking antibiotics may develop diarrhea, or even Clostridium difficile (C. diff), a potentially life-threatening infection. There is strong evidence that probiotic use before and during antibiotic treatment can significantly decrease risk of developing diarrhea and C. diff.

Traveling abroad? Many people have heard that probiotics can help prevent traveler’s diarrhea. However, the science is still mixed on whether or not probiotics have a statistically significant protective effect. There’s also mixed findings on which strains of probiotics may be most helpful in the prevention of traveler’s diarrhea.

2. Gut-disorders. For those of you suffering from irritable bowel disease (IBD), a recent meta-analysis of twenty-two random controlled trials found that probiotics may be effective in treatment of active ulcerative colitis, but the role of probiotics in treatment of Crohn’s disease is still mixed and requires more research.

A large area of probiotic research is looking at treatment for IBS. While the results are quite mixed, largely due to inconsistencies between studies, a recent meta-analysis found that probiotics were found to have a modest improvement in overall symptoms and quality of life.

3. Weight. Research has found that lean individuals have a different gut flora than obese, and even more interestingly, they’ve found that fecal transplants from lean mice can result in weight loss in obese mice . In a 2017 systematic review and meta-analysis, it was found that probiotic supplementation did result in significant weight loss and decrease in fat mass compared to a placebo in overweight and obese individuals; however the effect size was small and more research is needed on which strains are most effective.

4. Mental Health. While this is still a relatively new area of probiotic research, you’ve likely heard the term “gut-brain-axis” in the news or online. Research is showing that there is a link between microbiotia and stress-related behaviors, specifically anxiety and depression.

The proposed mechanisms are a bit complex, but the overarching idea is that an imbalance of harmful bacteria in the gut can lead to inflammation and immune activation, which may lead to deregulation of important brain chemicals.

Again, the research is still ongoing, but there is some evidence of probiotic supplementation reducing symptoms of both anxiety and depression.

5. Inflammation. This is a biggie, as we know that chronic inflammation can lead to numerous chronic diseases, including heart disease, stroke, type 2 diabetes, and possibly Alzheimer’s disease. Current evidence suggests that probiotics are key in reducing inflammation through multiple mechanisms of action. As a result, it’s thought that probiotics may play a role in preventing and treating these diseases, in addition to other lifestyle factors such as diet, weight, and smoking.

What About Probiotic Supplements?

The key to probiotics is to understand that the research is still ongoing and there likely isn’t a one-size-fits all. There are hundreds of thousands of species, and each may affect our health in different ways. And then there’s also the question of what happens with different combinations of each strain.

In general, there’s not enough evidence to make blanket recommendations for probiotics at high doses. If you suffer from bowel disease food allergies, or mental illness, it’s worth asking a medical professional about probiotics for your specific case.

Just remember, if your dietitian or doctor recommends taking probiotics: go slow. Ingesting large amounts of probiotics at one time can result in GI discomfort, including gas, bloating, constipation or diarrhea.

One other thing to keep in mind is the quality of the supplement. As supplements are not regulated by the FDA, there’s no assurance that what you’re buying is actually what you think you are.

When buying a probiotic supplement, look for products with a GMP stamp on the label. GMP stands for Good Manufacturing Practices, and it shows that the supplement you’re looking to buy has undergone voluntary verification of its quality and purity.

Natural Food Sources

However, just because supplements aren’t for everyone doesn’t mean you can’t still reap the benefits of probiotics through foods and beverages. Plus, many whole food sources may have additional benefits as probiotics can increase the bioavailability of vitamins and minerals.

Good sources of probiotics include:

• Fermented dairy including yogurt, kefir, and aged cheese
• Cultured vegetables, including Kimchi and Sauerkraut
• Miso
• Natto, a fermented soybean product found in Japanese cuisine
• Tempeh
• Kombucha
• Cultured non-dairy yogurts