With metabolic diseases on rise, there is a need to find novel ways to combat them and protect against diet-induced obesity. Recently a team of researchers exploring the role of flaxseed fibers on gut microbiota discovered that the fermentation of the fibers shows potential for improving metabolic health.
Prior to initiating the study, the researchers conducted a literature survey and came across articles suggesting the potential role of flaxseed fiber in hypolipidemia and cholesterol reduction. “However, there was no dietary intervention with flaxseed fiber in relation to gut microbiota modulation and improvement of metabolic health,” notes study coauthor Tulika Arora, “which created interest to perform this study.”
The researchers assigned mice to four different diets: a standard diet, a high-fat diet that contained no fiber, a high-fat diet that contained 10% indigestible cellulose fiber, and a high-fat diet that contained 10% flaxseed fiber. After conducting the dietary intervention for 12 weeks, measurements were taken of the amount of oxygen used, carbon dioxide produced, food and water consumed, energy expended, and glucose tolerance.
“We found that flaxseed fiber reduced obesity and increased energy expenditure in mice,” says Arora. “It altered bacterial composition with proliferation of bacterial taxa such as Bifidobacteria and Akkermansia, which was accompanied by shifts in bacterial metabolites short chain fatty acids. We also observed changes in global transcriptomics of nutrient-sensing enteroendocrine cells specifically in the large intestine, which has a higher density of gut bacteria. The cellulose group was similar to the chow [standard diet] group in all these observations. Thus, we concluded that fermentation of flaxseed fiber is important to improve metabolic health.”
Arora notes that flaxseed contains both insoluble and soluble fiber. The preparation used in the study consisted of the soluble mucilage fraction only. “We anticipate that the mucilage formed a gel-like consistency in water that made it accessible for bacterial degradation,” she observes. Another factor that likely influenced the results are the high levels of alpha linoleic acid in flaxseed grains. Alpha linoleic acid is known for its antioxidative properties and is one of a wide variety of nutrients found in flaxseed that may benefit human health.
“The results of our research in mice are indeed encouraging,” says Arora, “and suggest the potential for flaxseed fiber-rich foods in reducing obesity and improving metabolic health. However, mice and humans are different, and incorporating high levels (10% of diet) of fiber in the human diet is challenging. Therefore, it might be interesting to conduct a diet intervention with flaxseed fiber in human cohorts to find its potential for human relevance.”
Source: IFT
