Studies have shown that diet, such as Paleo, high fat vs low-fat diet or Western diet, greatly impacts the gut microbiota composition even more than genetics. Surprisingly, little is known how cooking certain foods might alter the gut microbiota. Since heat changes the chemical and physical properties of foods, researchers wondered if this too affects the gut microbiota.

Head researcher Peter Turnbaugh, PhD from the University of California, San Francisco (USA) and colleagues from various universities in the US, recently published a study in Nature Microbiology that explored how cooked vs raw food consumption affects the gut microbiota composition of humans.

Conducting studies in mice, the authors found that, when compared to normal mouse feed, vegetable diet, as well as meat diet both, induced a shift in microbiome composition. The microbiome of mice fed raw or cooked meat was similar in composition, but the microbiota of mice fed raw and cooked vegetable fundamentally differed from each other. In addition, mice fed raw vegetables lost more weight than cooked-fed mice because consumption of cooked vegetables impacted energy intake due to the greater digestibility of starch from the cooking process. With these results in mind, Turnbaugh and colleagues analyzed the gut microbiota of five healthy women and three healthy men aged 24–40 who ate either raw or cooked plant-based meals for three consecutive days.

The researchers discovered that like mice, the participants showed subtle but distinct differences following eating raw or cooked foods. The shifts observed in the gut microbiota could be due to the fact that cooking changes the physical structure of naturally occurring compounds found in foods. For example, cooking increases the digestibility of starches by gelatinizing starch.

Although the number of participants in this study was small, it sheds light on the importance of controlling cooking method and not just nutrient intake when investigating the diet-gut microbiome connection.

The authors of this study pose the hypothesis that humans could have co-evolved with our gut microbiomes in part due to cooking practices. Despite these findings, more long-term and large scale studies are needed to better understand how cooking foods could potentially affect weight and may pave the way for the development of new therapeutics that targets the gut microbiome.

 

Reference: Carmody RN, Bisanz JE, Bowen BP, et al. Cooking shapes the structure and function of the gut microbiome. Nature Microbiology, 2019. doi: 10.1038/s41564-019-0569-4 https://www.nature.c om/articles/s41564-019-0569-4

Allison Clark
Allison Clark
Allison Clark has a master in nutrition and health from Open University in Barcelona and a master in journalism. She is a freelance writer and nutritionist and has written various peer review papers about the role the gut microbiota plays in health, disease and endurance exercise performance. Allison is passionate about the role diet and the gut microbiota play in health and disease. Follow her on Twitter @Heal_your_Gut