The question “Should I be taking a probiotic?” is one that often crosses the minds of health-conscious individuals seeking to optimize their gut health. Maggie Stanislawski, PhD, an assistant professor in the University of Colorado Department of Biomedical Informatics (DBMI), often encounters this query. The answer, however, is far from straightforward. As she emphasizes, each person’s gut microbiome is distinct, and the effectiveness of many probiotic supplements available in grocery stores might not universally enhance gut health. Instead, she underscores the significance of cultivating a diverse microbiome.
Specializing in investigating the role of the gut microbiome in conditions like obesity and cardiometabolic disease, Stanislawski collaborates with fellow researchers at the CU School of Medicine to unravel the intricate relationship between dietary changes and the microbiome. Their efforts have unveiled intriguing insights, including potential links between shifts in gut microbiota and metabolic changes during dietary weight loss interventions.
Comparing Caloric Restriction and Intermittent Fasting
One notable collaboration involved Stanislawski and Vicki Catenacci, MD, an associate professor in the CU Department of Medicine. Together, they led a study that compared the effects of two widely recognized weight loss methods: intermittent fasting and traditional daily caloric restriction.
Stanislawski’s investigation delved into the impact of these interventions on participants’ gut microbiota, revealing positive outcomes in terms of microbiome diversification.
In the intermittent fasting group, participants followed a regimen of fasting for three non-consecutive days each week. On fasting days, they consumed approximately 25% of their regular caloric intake, while non-fasting days allowed unrestricted eating. Meanwhile, the caloric restriction group aimed for a consistent reduction of daily calories by around 30% of their weight maintenance requirements. Throughout the intervention, participants received behavioral support and guidance on enhancing overall diet quality, coupled with encouragement to elevate physical activity levels.
Diverse Microbiome, Diverse Health
The aim of the study was to decipher the potential benefits of intermittent fasting, a popular approach, especially when compared to conventional weight loss strategies. “Dr. Catenacci and her team were aiming to understand intermittent fasting because it’s become really popular, but some clinicians are hesitant to recommend it for weight loss,” Stanislawski explains. “This could give people who are trying to lose weight more options. As you might imagine, being able to eat whatever you want on a specific day, such as for a party or social engagement, is really helpful.”
Examining the initial three months of the one-year intervention, a pilot study revealed significant shifts in the microbiome of both participant groups.
Stanislawski elaborates on their findings: “We assess the microbiome through various diversity measures. One of them is alpha diversity, which signifies the variety of different microorganisms in a given environment. Generally, a more diverse and robust microbiome is linked to better health and leanness. This is likely because greater diversity enables a range of microbes to respond to diverse health influences.”
Their analysis of different alpha diversity measures during the initial three months showed consistent increases in both groups. “These findings are encouraging,” she remarks. “When we compared the two intervention groups, there weren’t any noticeable differences in terms of alpha diversity.”
The study outcomes suggest that, concerning microbiome diversity, both dietary weight loss strategies yield comparable success. Additionally, changes in the overall taxonomic structure of the microbiome composition were observed across all participants in both intervention groups.