Related Experiment Video
Updated: Feb 12, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Food Tolerance and Eating Behavior After Roux-en-Y Gastric Bypass Surgery
Cynthia M de A Godoy1, Luana Celi Silva Aprígio2, Eudes Paiva de Godoy3
1Bariatric Surgery Laboratory, Hospital Universitário Onofre Lopes HUOL, Av. Nilo Peçanha 620, Petrópolis, Natal, RN, CEP 59012-300, Brazil. cmagequipeunicad@gmail.com.
Background:
Roux-en-Y gastric bypass (RYGB) surgery often leads to food intolerance, especially protein intake.
Aim:
This is to investigate the association of food intolerance with protein intake and chewing parameters in patients who underwent RYGB surgery 2 years prior.
Methods:
An observational study was carried out in 30 patients aged between 18 and 60 years old with at least a 2-year postoperative period since undergoing RYGB surgery. A specific questionnaire was applied to obtain a food tolerance score; a masticatory efficiency, chewing cycles, and time were evaluated with a standard test based on the size of the fragmentation of almonds and of meat after a certain chewing time. Protein intake was evaluated by 24-h dietary recall.
Results:
Mean age was 42.3 ± 11.2 years; mean body mass index was 33 ± 6 kg/m2; and mean time since surgery was 4.9 years. The food tolerance score was 23.4 ± 3.3 points. There was no evidence of an association between food tolerance and chewing efficiency for meat (p = 0.28) nor between food tolerance and protein intake (Spearman correlation coefficient 0.03, p = 0.86). Regarding chewing efficiency with almonds, tolerance was higher in patients with optimal efficiency than among those with good and acceptable efficiency (p = 0.01).
Conclusions:
In the evaluation of mastication using almonds, food tolerance increased with the number of chewing cycles and with greater chewing efficiency; the same association was not found in the evaluation using red meat.
Related Concept Videos
Binge Eating Disorders
What is Behavior?
Gastric Motility
Peristaltic Waves and Chyme Formation
Upon food entry, the stomach initiates...
Gastric Emptying
Neural Regulation
Gastric Phase of Digestion
When food enters the stomach, it stretches the stomach walls and activates stretch receptors. This triggers local reflexes of the enteric nervous system, mediated through the myenteric plexus. These...

