I freely admit I am obsessed with research articles about eating habits. I hold out hope that this will eventually unlock the magic bullet to cure us of the modern plague of obesity. At a certain level, our patients need us to be captivated by such literature. We should feel fairly comfortable with the common knowledge that diets are effective if you stay on them and reducing the caloric density of foods can result in meaningful weight loss.
But what about how quickly we eat? In our fast-paced, heavily caffeinated society, we seem to shovel rather than chew. Ever since I was a medical resident, I have practically inhaled my food. Perchance I am operating under the erroneous and illogical assumption that if I don’t taste the food it won’t register as calories. True science has now enlightened me to the error in my thinking.
Dr. Eric Robinson and his colleagues conducted a brilliant systematic review of the impact of eating rate on energy intake and hunger (Am. J. Clin. Nutr. 2014;100:123-51). They included studies for which there was at least one study arm in which participants ate a meal at a statistically significant slower rate than that of a different arm. Twenty-two studies met the criteria for inclusion.
Available evidence suggests that a slower eating rate is associated with lower intake, compared with faster eating. The effect on caloric intake was observed regardless of the intervention used to modify the eating rate, such as modifying food from soft (fast rate) to hard (slow rate) or verbal instruction. No relationship was observed between eating rate and hunger at the end of the meal or several hours later.
Intriguing to me is the hypothesis that eating rate likely affects intake through the duration and intensity of oral exposure to taste. Previous studies have shown that, when eating rate is held constant, increasing sensory exposure leads to a lower energy intake. This seems to relate to our innate wiring that gives us a “sensory specific satiety.” In my understanding, sensory specific satiety turns off appetitive drive when you have had too much chocolate or too many potato chips and you feel slightly ill. Unfortunately, the food industry is on to this game and they have designed foods to be perfectly balanced to not render satiety. These foods can tragically be eaten ceaselessly.
Take-home message: If your patients cannot control the bad foods they eat, they should try to eat them more slowly.
Dr. Ebbert is professor of medicine, a general internist at the Mayo Clinic in Rochester, Minn., and a diplomate of the American Board of Addiction Medicine. The opinions expressed are those of the author and do not necessarily represent the views and opinions of the Mayo Clinic. The opinions expressed in this article should not be used to diagnose or treat any medical condition nor should they be used as a substitute for medical advice from a qualified, board-certified practicing clinician.