Exposure to written content eliciting weight stigmatization: Neural responses in appetitive and food reward regions.

OBJECTIVE: Neural activity in food reward- and appetite-related regions was examined in response to high-calorie (HC), low-calorie, and non-food pictures after exposure to written weight stigma (WS) content. Relationships with eating behavior (by Three-Factor Eating Questionnaire [TFEQ]), blood glucose, and subjective appetite were also explored. METHODS: Adults with overweight and obesity were randomized to read either a WS (n = 20) or control (n = 20) article and subsequently underwent brain scans while they rated pleasantness of food pictures. Fasting glucose, TFEQ, stigma experiences, and appetite were measured before reading the article, appetite after reading, and glucose and appetite again after the scan. RESULTS: A priori region of interest analyses revealed significant group differences in activation to HC > low-calorie food cues in the caudate and thalamus whereas exploratory whole-brain analyses suggested significant differences in regions including left insula, left thalamus, left inferior temporal gyrus, right lingual gyrus, and bilateral middle occipital gyrus and superior parietal lobule (p < 0.005 uncorrected, k ≥ 200 m3 ). No significant relationships were observed between the pattern of activation and TFEQ, glucose, or subjective appetite in the WS group. CONCLUSIONS: Exposure to WS was associated with increased responsiveness to HC food content in the dorsal striatum and thalamus in individuals with overweight and obesity.

Changes in Food Cravings and Eating Behavior after a Dietary Carbohydrate Restriction Intervention Trial.

Compared to low-fat diets, low-carbohydrate (CHO) diets cause weight loss (WL) over a faster time frame; however, it is unknown how changes in food cravings and eating behavior contribute to this more rapid WL in the early phases of dieting. We hypothesized that reductions in food cravings and improved eating behaviors would be evident even after a relatively short (4-week) duration of CHO-restriction, and that these changes would be associated with WL. Adult participants (n = 19, 53% males, mean ± SD: BMI = 34.1 ± 0.8 kg/m2; age 40.6 ± 1.9 years) consumed a CHO-restricted diet (14% CHO, 58% fat, 28% protein) for 4 weeks. Before and after the intervention, specific and total cravings were measured with the Food Craving Inventory (FCI) and eating behaviors assessed with the Three-Factor Eating questionnaire. Food cravings were significantly reduced at week 4, while women had significantly greater reductions in sweet cravings than men. Dietary restraint was significantly increased by 102%, while disinhibiton and hunger scores were reduced (17% and 22%, respectively, p < 0.05). Changes in cravings were unrelated to changes in body weight except for the change in high-fat cravings where those who lost the most weight experienced the least reductions in fat cravings (r = -0.458, p = 0.049). Changes in dietary restraint were inversely related to several FCI subscales. A short-term, low-CHO diet was effective in reducing food cravings. These data suggest that in subjects that have successfully lost weight on a low-CHO diet, those who craved high-fat foods at the onset were able to satisfy their cravings-potentially due to the high-fat nature of this restricted diet.

Can the Palatability of Healthy, Satiety-Promoting Foods Increase with Repeated Exposure during Weight Loss?

Repeated exposure to sugary, fatty, and salty foods often enhances their appeal. However, it is unknown if exposure influences learned palatability of foods typically promoted as part of a healthy diet. We tested whether the palatability of pulse containing foods provided during a weight loss intervention which were particularly high in fiber and low in energy density would increase with repeated exposure. At weeks 0, 3, and 6, participants (n = 42; body mass index (BMI) 31.2 ± 4.3 kg/m²) were given a test battery of 28 foods, approximately half which had been provided as part of the intervention, while the remaining half were not foods provided as part of the intervention. In addition, about half of each of the foods (provided as part or not provided as part of the intervention) contained pulses. Participants rated the taste, appearance, odor, and texture pleasantness of each food, and an overall flavor pleasantness score was calculated as the mean of these four scores. Linear mixed model analyses showed an exposure type by week interaction effect for taste, texture and overall flavor pleasantness indicating statistically significant increases in ratings of provided foods in taste and texture from weeks 0 to 3 and 0 to 6, and overall flavor from weeks 0 to 6. Repeated exposure to these foods, whether they contained pulses or not, resulted in a ~4% increase in pleasantness ratings. The long-term clinical relevance of this small increase requires further study.

A blended- rather than whole-lentil meal with or without α-galactosidase mildly increases healthy adults' appetite but not their glycemic response.

BACKGROUND: Disrupting the physical structure of pulses by blending them or by using a digestive supplement (α-galactosidase) to reduce intestinal discomfort could potentially negate the previously observed beneficial effects of whole pulses of lowering appetitive and glycemic responses because of more rapid digestion. OBJECTIVE: We hypothesized that blended lentils, α-galactosidase, or both increase postprandial appetite and blood glucose responses vs. whole lentils. METHODS: Men and women [n = 12; means ± SDs body mass index (kg/m(2)): 23.3 ± 3.1; aged 28 ± 10 y] consumed breakfast meals containing whole (W), blended (B), or no lentils [control (C)], each with 3 α-galactosidase or placebo capsules in a randomized, crossover, double-blind placebo-controlled trial. Between each test day there was a 3- to 5-d washout period. RESULTS: Mixed-model ANOVA showed effects of meal on postprandial appetite and glucose (P = 0.0001-0.031). The B meal resulted in higher postprandial appetite ratings than did the W meal but not the C meal for hunger, desire to eat, and prospective consumption (Δ = 0.4-0.5 points; P = 0.002-0.044). Postprandial glucose concentration was 4.5 mg/dL lower for the B meal than for the C meal (P < 0.0001) but did not differ from the W meal. There were no main effects of α-galactosidase, but there were meal × α-galactosidase interaction effects, with a greater postprandial desire to eat and lower postprandial fullness with the B meal than with the 2 other meals in the placebo condition but not in the α-galactosidase condition. CONCLUSIONS: Blending lentils increased appetite (∼6%), but not glycemic response, compared with whole lentils, whereas α-galactosidase did not. Both B and W meals may be consumed (with or without an α-galactosidase supplement) with little impact on appetite, without increasing glycemic response. This trial was registered at clinicaltrials.gov as NCT02110511.