Data provided by a new study published in the Journal of Health Psychology emphasizes an obvious need to explore effective methods for teaching appropriate meal portion control. The study participants who were given larger servings of food consumed more than those who were provided with smaller servings; even after they were informed of the impact of portion size on consumption. Furthermore, this research from the University of New South Wales demonstrated that learning how to engage in mindful eating did not decrease food intake by a significant quantity among those given larger servings. Research has clearly shown that appetite and eating behaviors are centrally regulated by the hypothalamus through the reception and processing of neural, metabolic, and endocrine signals from the body. Additionally, neural-driven external factors such as memory, social situations, the time of day, stress, the taste or smell of food, the nutrient content in the meal, and exercise will influence the quantity of food intake. According to the study at hand, even if people are formally informed of these factors, they have little conscious control over portion control if their plate is filled with excess food. “If no effective approaches are found, it may be necessary to develop policy-related changes to provide a healthier food environment for people,” said Dr. Lenny Vartanian, a senior lecturer in the UNSW School of Psychology and an author of the paper. We all are aware that common portion sizes in restaurants, and even at home, far exceed those necessary to meet energy needs. According to statistical data, portion sizes in both environments have increased exponentially since the early 1970s, and are thought to have contributed to the rising prevalence of obesity.
The research team’s study of 96 women is the first to examine the effectiveness of educating people about this phenomenon. Participants were served either a 350 or 600 g portion of macaroni pasta with tomato sauce for lunch, and some were provided education on factors that lead to increased food consumption. Those in the education group (mindful eating group) were given a brochure explaining that external factors, such as mood, advertising, portion size, and social and cultural influences can contribute to overeating. Those in the mindfulness group were also taught how to focus on internal sensations related to the meal, such as the taste of food and feelings of hunger and satiety, before they consumed the meal. “Neither of these brief exercises reduced the effects of portion size. Overall, participants in the larger portion group consumed about a third more pasta – 69 grams – than those in the smaller portion group”, Dr. Vartanian states. This difference equaled about 87 kcals of extra energy. If similar overconsumption (which may seem minor in itself) took place during three separate meals for a total of five days in a given week, an additional 1300 kcals would be consumed. Over a month, this would equal the caloric equivalent of 1.5 lbs of fat – clearly the extra bites add up quick.