Flaxseed beats probiotics for improved insulin sensitivity & altered microbiota
The study saw 58 obese postmenopausal women given a daily dose of either L. paracasei, 10 g of flaxseed mucilage - which contained about 30% dietary fibres - or a maltodextrin placebo for six weeks.
The researchers then looked at faecal DNA to identify changes to gut microbiota.
They sought to explore the theory that obesity-related metabolic diseases were accompanied by alterations in gut bacteria gene composition and abundance and asked whether gut microbiota changes could cause metabolic diseases or if they were just a consequence.
Published in the British Journal of Nutrition, the study found the flaxseed mucilage altered 33 metagenomic species including decreasing eight Faecalibacterium species. However, L. paracasei did not change metabolic markers compared with the placebo nor did it increase the abundance of the Lactobacillus species.
Flaxseed also improved insulin sensitivity, although this was not linked to the changes to microbiota.
“There were no differences in the anthropometric measures between groups; however, the participants in the L. paracasei F19 group had significantly impaired insulin sensitivity compared with the flaxseed mucilage group, and a significantly lower bacterial gene count compared with the placebo group,” they wrote.
The researchers noted it was possible the probiotic intervention would have been more effective if it had been given as part of a fermentable milk product, a matrix that may enhance probiotic efficacy.
The flaxseed group also reported more adverse events, such as increased flatulence and more frequent defecation and looser stool consistency.
The study was conducted by researchers at the University of Copenhagen and the Aarhus University in Denmark and the National Institute of Agronomy Research in France as well as the Strategic Innovation Centre of Swedish company Arla, which provided the probiotics and funding.
The participants were women aged 40–70 years, with at least a year since last menstruation and a body mass index (BMI) of 30–45kg/m2 and waist circumference of over 80cm.
Source: British Journal of Nutrition
Published online ahead of print, doi:10.1017/S0007114515001786
“Dietary modulation of the gut microbiota – a randomised controlled trial in obese postmenopausal women”
Authors: L. K. Brahe, E. Le Chatelier, E. Prifti, N. Pons, S. Kennedy, T. Blædel, J. Håkansson, T. Kastrup Dalsgaard, T. Hansen, O. Pedersen, A. Astrup, S. Dusko Ehrlich and L. H. Larsen