Study: Severely Obese Dont Feel Full

PROVIDENCE, R.I.A physiological response may partially explain why severely obese individuals may not feel satisfied after eating and often have difficulty controlling the amount of food they consume during a meal, according to new research from The Miriam Hospital.

Researchers focused on habituation, or the idea that continual exposure to a specific food decreases ones physical response to that food. Habituation theory suggests that if one habituates, or adjusts, slowly to food cues, they are less likely to feel satisfied with that particular food and can consume more of it.

In the study, published online in Obesity Surgery, the research team looked at saliva production following repeated exposure to lemon juice. They compared the responses of two groups, severely obese patients preparing for bariatric surgery and normal weight individuals, and found that the bariatric surgery candidates continued to salivate at a consistent rate throughout the tastings, indicating that very little habituation occurred. Meanwhile, the salivation rate of the normal weight controls decreased with successive exposures to the lemon juice.

The failure of bariatric surgery candidates to habituate suggests that satiation, or the feeling of fullness while eating, is impaired in this population. This could play a role in the inability of some severely obese individuals to regulate or control the amount of food that they eat during a meal, said one researcher.