Study under review: Probiotic supplementation prevents high-fat, overfeeding-induced insulin resistance in human subjects
Probiotics are microorganisms that can integrate into the microbiota of our gut in a beneficial way. They are living organisms that can colonize the gastrointestinal (GI) tract, and potentially crowd out some harmful microbiotic species.
Gut microbiota interact with their host in a number of ways. One is by contributing to intestinal metabolism through excretion of their own enzymes into the GI lumen, or through their own metabolism, particularly the fermentation of some types of fiber into short-chain fatty acids (SCFAs). These SCFAs support uptake of positively charged ions, also known as cations (e.g., Ca, Mg, K, Na), and can be taken up and metabolized further in the body. Microbiota are also involved in folate and biotin biosynthesis.
Since our food contains hundreds of thousands, maybe millions, of biochemical compounds, and since microbiota changes metabolism and uptake of nutrients, different microbiota can induce different changes in the host body. The purported effects range from changes in feeding efficiency (i.e., how much food is taken up in animals), levels of gastric upset, and immune function under stress to reducing antibiotic-induced diarrhea and improving resistance to opportunistic infections. Figure 1 shows some of the ways that an overly-permeable gut lining, influenced by microbiota balance, can impact conditions such as type II diabetes.
Adapted from: Gravitz, Nature Outlook, 2012.
Previous studies have shown that distinctive microbiological profiles are associated with poor metabolic function in people and animals with chronic conditions. A couple examples are shown in Figure 2. Furthermore, probiotics may help ameliorate metabolic dysfunction in the host. However, whether probiotic administration can prevent the impairment of glucose homeostasis induced by overfeeding in humans has not been studied. The purpose of this study was to answer that question.
Gut microbiota play a large role in health, including potentially in metabolic disorders associated with diabetes and obesity. The goal of this study was to determine whether probiotics that influence the microbiota could help prevent glucose impairment induced by overfeeding in humans.
Other Articles in Issue #06 (April 2015)
Blueberries every day keeps high blood pressure at bay
Blueberries may be a simple way to lower this important cardiovascular disease risk factor.
Driving a car blindfolded: the neurobiology of appetite
One of the most important contributers to weight gain may be modern hyperpalatable food. By Margaret Leitch
Can the paleo diet make metabolic syndrome ancient history?
Can a paleo diet improve risk factors for those who already have metabolic syndrome?
Kick the can: how BPA in canned drinks impacts blood pressure
BPA is everywhere, from receipts to canned foods. How exactly does it impact blood pressure?
The gut microbiome’s role in type I diabetes
Development of type 1 diabetes in infants isn’t fully understood. This study explores the role of the infant microbiome.
Curry… brain food?
The widely-used Indian spice turmeric contains curcumin, which may help with DHA synthesis.
Can fiber change your emotions?
Due to the “gut-brain axis”, feeding gut bacteria might affect your emotions.
- Interview: Mike Ormsbee, Ph.D.
- Interview: Duane Mellor, Ph.D.
Another benefit of dark berries: blood sugar control
Using berries to better control blood sugar? Believe it.