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Early probiotic supplementation decreases binge eating and food addiction one-year post-RYGB

Updated: Oct 21, 2022

The outcomes from a randomised controlled trial have shown that early probiotic supplementation may decrease binge eating and symptoms of food addiction one-year after Roux-en-Y gastric bypass (RYGB) surgery, according to Brazilian researchers from the Universidade Federal do Paraná, Departamento de Clínica Cirúrgica, Curitiba, PR. The outcomes were reported in the paper, ‘Probiotic supplementation attenuates binge eating and food addiction 1 year after Roux-en-Y gastric bypass: a randomized, double-blind, placebo-controlled trial’, published in the journal Arquivos Brasileiros De Cirurgia Digestiva (Brazilian Archives Of Digestive Surgery).

The authors stated that eating disorders are serious psychiatric illnesses characterised by abnormal eating behaviour and/or excessive preoccupation with body weight. The prevalence of eating disorders among individuals undergoing bariatric surgery varies according to the assessment method, but it seems to be higher than that in the general population. Indeed, binge eating disorder (BED) is the second most common single disorder in bariatric patients.

Recently, researchers have investigated “food addiction” (FA) among individuals undergoing bariatric surgery. Energy-dense food are generally rich in sugar, fat, and/or salt and are consequently very palatable. These foods are excessively stimulating for the reward pathways of the brain that can promote craving, an uncontrollable urge, an insatiable desire to continue eating and trigger symptoms, but still not so associated with abstinence.

Unfortunately, there are significant limitations in the ability to detect, prevent, and treat these disorders. The classic treatment for eating disorders is psychotherapy that may or may not be combined with medication. A new approach for treating psychiatric disorders is the use of probiotics and prebiotics as modulators of the microbiota-gut-brain axis, also known as psychobiotics.

However, studies evaluating the influence of probiotic supplementation on psychological or behavioural factors in individuals undergoing bariatric surgery are still lacking. Therefore, the aim of this study was to analyse the influence of probiotic supplementation on BED and FA in individuals undergoing RYGB.

In this is a randomized, double-blind, placebo-controlled trial, 101 patients received probiotic (Lactobacillus acidophilus NCFM and Bifidobacterium lactis Bi-07) or placebo supplements for 90 days after bariatric surgery, starting on the seventh postoperative day. They were evaluated preoperatively (T0) and postoperatively at 90 days (T1) and 1 year (T2) after surgery. The Yale Food Addiction Scale (YFAS) and Binge Eating Scale (BES) were applied to assess food addiction and binge eating, respectively.

Using the Binge Eating Scale (BES), the participants were instructed to select the answer that best represented their response, and the final scores were obtained by (1) the BES total score: the sum of the points of each item (ranging from 0 to 46), thus measuring the binge eating severity, and (2) the binge eating severity classification (according to the BES total score) as follows: (1) score=17: none; (2) score=18-26: moderate; and (3)score=27: severe binge eating. The Yale Food Addiction Scale (YFAS), a self-report questionnaire that detects symptoms of addictive eating behaviours, was used to assess FA.


Out of 110 patients initially selected, 70.3% completed the supplementation protocol, and 44 were followed up for one year after RYGB surgery. Most of the patients were female (87.30%), with an average age of 40 (±11.25) years old. Participants were randomised in the placebo and probiotic groups and had 99% adherence to supplementation in both groups. None of the participants reported adverse effects during the intervention. Anthropometric and eating behaviour data of individuals before and after RYGB were similar between the groups regarding anthropometry at all time points. Body weight, BMI, and age seemed to have no impact on the results.

The authors reported that YFAS symptoms and BES scores were higher at the T0 time point in the probiotic group than in the control. However, there was a decrease in YFAS and BES at T1 compared to T0 in both groups and a trend toward an increase in these values at T2 compared to T1 (Figure 1). The probiotic group behaved differently from the placebo group at T2, with a lower increase in the number of YFAS and a continued decrease in BES values. These results highlight the impact of probiotic supplementation; even though this group had higher values before the intervention (T0), at T2, they had fewer YFAS symptoms and a lower BES score.

Figure 1: Predictive number of symptoms of food addiction and Binge Eating Scale (BES) of individuals in the presurgical moment and postsurgical of 3 months and 1 year of Roux-en-Y gastric bypass. T0, presurgical moment; T1, 3 months postsurgical moment; T2, 1 year postsurgical moment; YFAS, Yale food addiction scale; FA, food addiction; . *Statistical difference between groups. Generalized additive models for location scale and shape (GAMLSS) was used as statistical analyses.

There was a significant effect of probiotic treatment observed one-year after surgery compared to the placebo group in both YFAS and BES (p=0.037 and p=0.030, respectively), which was not the case at T1 (0.076 and 0.674, respectively).

The researchers believe this is the first time early probiotic supplementation has been given to individuals who underwent RYGB surgery with the aim of verifying the impact on FA and binge eating three months and one year after bariatric surgery. Probiotic supplementation was associated with an attenuation of the binge eating score and FA symptoms one year after bariatric surgery.

“The findings demonstrate the ability of early probiotic supplementation may decrease binge eating and symptoms of food addiction one-year after RYGB surgery,” they authors concluded. “Future research should also examine the impact of early and late probiotic supplementation on eating disorders, as well as those effects in nonobese and non-bariatric individuals.”

Further information

To access this paper, please click here


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