Weight and the Microbiome

Often people have weight issues — despite rigorous diets. With CFS, many patients are skinny and unable to gain weight while others eat only celery and stay obese. The fat CFSer often has their fatigue ascribed to being obese by physicians and ascribe the issue to the patient’s attitude and lack of wiliness to change.

There can be DNA and epigentic causes (for example, my weight increase with stress and reduces when the stress is significantly reduced). For example, my own DNA report from 23andMe shows:


In this post, I am going to look at bacteria that are associated with being obese or lean.

  • “So far, evidence of an antiobesity effect of different lactobacilli and bifidobacteria has been mainly obtained from animal models of dietary-induced obesity. Using these experimental models, a substantial number of studies have reported reductions in weight gain and, in particular, fat tissue mass at different locations following administration of bacteria, as compared with controls.” [2016]
  • ” Of the four probiotic candidates, the bifidobacteria B. longum BORI and B. bifidum BGN4, developed in our laboratory, and L. acidophilus AD031 showed excellent anti-obesity effects and suppressed lipid deposition in liver.”[2016]
  • “Members of the Firmicutes phylum, and Bifidobacterium longum, were more abundant in the lean group.” [2016]
  • “Cross-sectional studies have shown that certain bacterial populations – such as Akkermansia muciniphila, Faecalibacterium prausnitzii, Methanobrevibacter smithii and Christensenellaceae – are better represented in lean individuals compared to those who are overweight or metabolically unhealthy.” [2016]
  • “The Bacteroides fragilis group were found at high concentrations in obese and overweight children when compared with the lean ones (p 0.015). The obese and overweight children harboured higher numbers of Lactobacillus spp. than lean children (p 0.022)…. Furthermore, a negative correlation between BMI and Bifidobacterium spp.  (r = -0.22; p 0.039) was observed. ” [2016]
  • “Our results suggest that the Mediterranean diet could be a useful tool to restore potentially beneficial members of the gut microbiota [reducing obesity], although the stability of these changes over time still remains to be assessed… better than a low fat high carbohydrate diet” [2016]
  • “… suggesting a causal role of gut bacteria in development of obesity-related metabolic diseases and a potential for microbiota modulation as a strategy to improve host health…the positive association with a healthy metabolic profile suggested for B. longum and F. prausnitzii” [2015]
  • “The obese children have a lower amount of Bifidobacteria and higher amount of E.coli (smaller B/E ratio) compared to normal non-obese children.” [2015]
  • Potential probiotic Bifidobacterium animalis ssp. lactis 420 prevents weight gain and glucose intolerance in diet-induced obese mice [2014].
  • “These results may contribute to explain the body weight gain reducing effects of the Rosemary Extract.” [2014]
  • “The results show that resveratrol (200 mg per kg per day) significantly lowers both body and visceral adipose weights, and reduces blood glucose and lipid levels in HF mice. Resveratrol improves the gut microbiota dysbiosis induced by the HF diet, including increasing the Bacteroidetes-to-Firmicutes ratios, significantly inhibiting the growth of Enterococcus faecalis, and increasing the growth of Lactobacillus and Bifidobacterium.” [2014]
  • “The acquired obesity observed in patients treated with [antibiotic] vancomycin may be related to a modulation of the gut microbiota… Vancomycin was associated with a 10% BMI increase ” [2013]
  • “Analysis of the eligible articles pointed out that Lactobacillus gasseri SBT 2055, Lactobacillus rhamnosus ATCC 53103, and the combination of L. rhamnosus ATCC 53102 and Bifidobacterium lactis Bb12 may reduce adiposity, body weight, and weight gain.” [2014]
  • “The fecal concentration of Lactobacillus reuteri was positively correlated with BMI (coefficient=0.85; 95% confidence interval (CI) 0.12-0.58; P=0.02) in agreement with what was reported for Lactobacillus sakei.” (i.e. more means fatter!) “As reported, B. animalis (coefficient=-0.84; 95% CI -1.61 to -0.07; P=0.03) and M. smithii (coefficient=-0.43, 95% CI -0.90 to 0.05; P=0.08) were negatively associated with the BMI. Unexpectedly, E. coli was found here for the first time to negatively correlate with the BMI (coefficient=-1.05; 95% CI -1.60 to -0.50; P<0.001).” [2013]
  • Obesity-associated gut microbiota is enriched in Lactobacillus reuteri and depleted in Bifidobacterium animalis and Methanobrevibacter smithii.[2012]”

Bottom Line To Reduce Weight

There is likely no magic formula in the research above. Most diet focus on reducing calories and not trying to shift the bacteria towards the lean mixture. For another author’s view, see this on DietVsDisease.org

Lactobacillus is often associated with obesity for many strains. Yogurt and other lactobacillus food are likely good for increasing weight but not decreasing weight.

  • ENCOURAGE faecalibacterium prausnitzii, see this earlier post.
  • Lactobacillus gasseri  – which Swanson sells ($15 for 120 capsules of 3 BCFU)
  • Bifidobacterium longum – you want it to be without any lactobacillus.
  • Bifidobacterium animalis subsp. lactis (BB-12®)


  • For a list of Bifidobacteri mixtures and their contents, see this post. Phillips Colon Health Probioplus DDS Five Strain looked like a good choice, but appears to be off the market now 😦
  • Change of diet towards Mediterranean Diet
  • Increase use of Rosemary in cooking
  • Resveratrol – Grapeseed, red wine, or as a supplement
  • Reducing Bacteroides fragilis — using the post on OTC medicines, we see taking Calcium supplements (including laxatives) reduces this group.