Italian researchers conducted a meta-analysis which explored the effects of live microorganisms on Type 1 and Type 2 diabetes. They found that probiotics and synbiotics helped to restore gut microbiome balance, improved gut barrier function and reduced inflammation. Moreover, they determined synbiotics could offer an even greater benefit to controlling blood sugar levels.
“Considering the intricate dietary challenges faced by people with diabetes, who require adequate self-care behaviors to navigate and manage their condition effectively, the potential benefits of probiotics and synbiotics become even more pertinent,” the researchers wrote. “Additionally, the study underscores the need for further tailored research that considers variables such as strain types and geographical factors to deepen the understanding of the role of these interventions in diabetes care.”
A pivotal role in health
According to research in Scientific Reports, 465 million adults have either Type1 or Type 2 diabetes, and this number is expected to grow to 700 million by 2045. This problem is exacerbated by the challenges of achieving stable blood glucose levels in this population.
“While contemporary management approaches have achieved notable progress in glycemic control, in some cases, they still fail to ensure optimal patient outcomes,” the researchers noted. “Consequently, a substantial segment of the diabetic population still grapples with suboptimal glycemic control.”
However, in Type 1 diabetic people, the body’s immune system targets insulin-producing beta cells, which leads to insulin deficiency. Here, the gut microbiome experiences changes showing a possible link between microbiota alterations and an autoimmune response that impacts the severity of that diabetes.
Type 2 diabetes works differently.
“[It’s] characterized by metabolic disturbance and is primarily associated with insulin resistance due to factors such as genetics and lifestyle,” the researchers wrote. “In [Type 2 diabetes], gut dysbiosis has been observed, contributing to increased gut permeability and chronic inflammation, further exacerbating insulin resistance.”
The intestines hold the intricate web of microorganisms that make up the microbiome and hold a key to metabolic health. The gut microbiome and probiotics are “potential gamechangers” to tacking diabetes, they added.
Review details
The researchers reviewed 41 randomized clinical trials from databases where information was gathered up until October 2023. The studies—which examined the addition of probiotics and/or synbiotics to patient treatment—included 2,991 adults with either type of diabetes, most of whom were from Iran.
The review explored three measures of glycemic control: HbA1c levels, FPG and serum insulin levels. HbA1c levels show mean blood sugar over approximately three months. FPG measures blood glucose after an overnight fast because the body goes into glucose homeostasis in a fasting state. Finally, serum insulin levels allow for metabolic responses to be evaluated, giving insight into endogenous insulin secretion and how it interplays with glucose.
“For serum insulin levels, our meta-analysis revealed a moderate but statistically significant effect size, indicating a potential role for probiotics and synbiotics in insulin regulation,“ the researchers wrote. “Specifically, our subgroup analysis indicated that synbiotics were particularly effective in improving insulin levels, with a moderate but statistically significant effect size, suggesting that synbiotics may offer additional benefits over probiotics alone in regulating insulin levels.”
The type of bacterial strain also played a role in interventions. Specific Lactobacillus and Bifidobacterium lactis strains had sizeable effects on the patients, suggesting therapeutic interventions may be specific to certain strains.
The study had some limitations. Several variables impact diabetes, and the researchers could not account for all of them, including for diet, physical activity, medication type and how long patients had experienced diabetes. All these factors can influence metabolic health and glycemic control.
“Additionally, the type of diabetes medication used by the participants might modulate the gut microbiota and interact with the effects of the interventions, potentially confounding the results,” the researchers explained. “However, our focus on including only randomized clinical trials in the meta-analysis may mitigate some of these concerns, though not entirely.”
Source: Clinical Nutrition
“Probiotics and synbiotics for glycemic control in diabetes: A systematic review and meta-analysis of randomized controlled trials”
Authors: Irene Baroni et al.
