(NaturalNews) Obese and lean individuals have different gut flora composition. The gut microbiota of mice and humans are similar, with Firmicutes and Bacteroidetes dominating. At this point it's not clear exactly which species are important in weight management. Some studies show reduced numbers of Bacteroidetes in obese subjects, while others point to lower levels of beneficial bacteria like Lactobacillus.
Even though diet will affect gut flora composition, most studies conclude that gut flora on it's own has an effect on weight. Alteration of the gut microbiota can be an important part of a weight loss program.
Several mechanisms have been proposed as to how gut flora regulates weight. Inflammation, energy from polysaccharides, insulin sensitivity and energy expenditure and storage are all affected by gut flora.
What you eat affects the gut flora composition, but it can also be hypothesized that it can happen the other way around; that gut flora partly determines what you eat. People with gut dysbiosis and especially yeast overgrowth often feel sugar cravings. Gut flora can probably influence food cravings and thereby play a part in determining dietary choices.
Obesity is hereditary, and the importance of gut flora shouldn't be underestimated. Flora is passed on from mother to child during birth, breastfeeding and early years. The child also comes in contact with microorganisms from other family members. "Obese gut flora" is passed on to the child. Children born via caesarean have double the risk of becoming overweight, according to research by Harvard scientists. The obesity increase has been linked to a lack of exposure to good bacteria which may be found in the vaginal wall.
Differences in intestinal microflora during the first year of life have been associated with higher risk of obesity later in life. Especially low levels of Bifidobacteria make children more susceptible to weight gain.
Obese individuals usually have a dysfunctional gut flora with higher numbers of LPS-containing microbiota and methane-producing bacteria. LPS, Lipopolysaccharide, is linked to obesity, leaky gut and low-level chronic inflammation.
Colonization of germ-free mice with gut flora from either obese or lean mice, leads to significantly greater increase in total body fat in those colonized with "obese microbiota." Animal studies further show that probiotic supplements with Lactobacillus and Bifidobacterium species help maintain a healthy bodyweight and promote weight-loss. Cattle treated with antibiotics store a lot of fat, and this is one of the reasons why these drugs are used so frequently in feedlots.
How to incorporate this info into your weight loss program
A healthy diet with reduced consumption of sugar, processed carbohydrates, most vegetable oils, anti-nutrients, etc. will on it's own promote weight loss and a healthier gut flora.
Additional gut flora modifications can also be an important part of a weight-loss plan. Simply eating yoghurt will not make any substantial difference in most people. Minimally washed organic plants and plant products, fermented foods and probiotic supplements are all good sources of beneficial bacteria. Prebiotics, soluble fiber that feed good bacteria, can be found in leeks, onions, apples etc.
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