A new Japanese study reveals that chewing food slowly benefits health in various ways. In today’s fast-paced life, many people eat their meals in a rushed, stressful manner. However, ancient cultures knew the importance of being mindful while eating and expressing gratitude for their food.
Aside from the mental benefits, chewing slowly improves physical wellbeing also. Various scientific studies have shown how eating mindfully and savoring the experience help prevent obesity and weight gain.
Usually, the chewing process increases the energy expenditure associated with metabolizing food. It also enhances intestinal motility, which helps improve the heat generated in the body while digesting food. This process is known as diet-induced thermogenesis (DIT).
However, scientists couldn’t determine how chewing slowly triggers DIT in the body before this study. Recently, Dr. Yuka Hamada and Professor Naoyuki Hayashi from Waseda University, Japan, began researching the mechanism behind this process. They’ve published the study proving the correlation between chewing and DIT in the journal Scientific Reports.
DIT, otherwise known as the thermic effect of food consumption, boosts energy expenditure above the basal fasting level. This factor helps prevent weight gain since it increases metabolism. Previously, the team discovered that slow eating and thorough chewing enhanced DIT and increased blood circulation in the splanchnic region of the abdomen.
While these studies linked slow chewing with increased digestion and absorption of nutrients, a few questions were left unanswered.
Hayashi explains, “We were unsure whether the size of the food bolus that entered the digestive tract contributed to the increase in DIT observed after slow eating. Also, do oral stimuli generated during prolonged chewing of food play any role in increasing DIT? To define slow chewing as an effective and scientific weight management strategy, we needed to look deeper into these aspects.”
Japanese Study Proves That Chewing Slowly Improves Health
To discover the answers, the team designed their recent study to include only liquid food, thus excluding the effects of the food bolus. A food bolus starts as a small, round food mass in the mouth during the early stages of digestion.
The study included three trials conducted at different times. Researchers asked volunteers to swallow 20-mL liquid test food usually every 30 seconds in the control trial. The volunteers kept the liquid food in their mouths for thirty seconds without chewing in the second trial. This allowed them to taste the food for a more extended period before swallowing.
Finally, in the third trial, they studied how chewing and tasting impacted metabolism and blood circulation. The volunteers chewed the liquid food for 30 seconds at once per second before swallowing it. The research team measured hunger and fullness levels, gas-exchange variables, DIT, and splanchnic circulation before and after volunteers drank the liquid.
The researchers gained great understanding from the results of their study. They found that no difference occurred in hunger and fullness scores throughout the trials.
However, as Hayashi describes:
“We found DIT or energy production increased after consuming a meal, and it increased with the duration of each taste stimulation and the duration of chewing. This means irrespective of the influence of the food bolus, oral stimuli, corresponding to the duration of tasting food in the mouth and the duration of chewing, increased DIT.”
The longer the participants chewed and tasted their food, the greater the gas exchange and protein oxidation. Also, blood flow in the splanchnic celiac artery increased. Since this crucial artery supplies the digestive organs with blood, the upper gastrointestinal tract showed a more significant response to chewing.
So, the study proved that chewing more slowly can help prevent metabolic syndrome and weight gain by boosting energy expenditure. In other words, slowing down while you eat uses more energy, therefore staving off obesity and other weight-related problems.
Hayashi concludes, “While the difference in energy expenditure per meal is small, the cumulative effect gathered during multiple meals, taken over every day and 365 days a year, is substantial.”
The team believes that slow eating and thorough chewing could provide simple solutions for weight management moving forward.
How to Practice Mindful Eating
Proper food nourishes the body with essential nutrients and induces a relaxed mind. Yogis refer to these foods as sattvic, as they instill the body and mind with positive, balanced energy. These foods include fresh, whole foods like fruits, nuts, seeds, and grains.