The effects of lisdexamfetamine dimesylate on eating behaviour and homeostatic, reward and cognitive processes in women with binge-eating symptoms: an experimental medicine study

Lisdexamfetamine dimesylate (LDX) is the only drug currently approved by the FDA for the treatment of Binge-Eating Disorder (BED), but little is known about the behavioural mechanisms that underpin the efficacy of LDX in treating BED. We examined the behavioural and neural effects of an acute dose of LDX (50 mg) in 22 women with binge-eating symptomatology using a randomised, crossover, double-blind, placebo-controlled experimental medicine design. LDX reduced self-reported appetite ratings and intake of both a pasta meal and a palatable cookie snack. LDX also decreased the eating rate of pasta but not of cookies and reduced self-reported liking ratings for pasta at the end of the meal. When viewing food pictures during an fMRI scan, LDX reduced activity bilaterally in the thalamus. LDX enhanced sustained attention and reduced impulsive responding in a continuous performance task but had no effect on emotional bias or working memory. These results suggest the observed effects of LDX on food intake (and by implication the efficacy of LDX in treating BED) may be related to the actions of the drug to enhance satiety, reduce food-related reward responding when full and/or increase cognitive control. Novel pharmacotherapies for BED might be most effective if they have a broad spectrum of effects on appetite, reward and cognition.

Factors Influencing Weight Loss Attempts and Long Term Weight Loss Maintenance

Background: A cross-sectional study aimed to determine the factors association with repeated weight loss attempts, and weight loss maintenance. Methods: The study was conducted in the main public hospitals in Benghazi, Libya. A total sample of 300 participants who suffered from weight gain or/ obesity and had a history of trying of weight loss. The data were collected by using a questionnaire that include all the factors that may affect the weight loss process such as social, psychological, health, factors related to diet , and daily behavior factors. Results: The majority of participants 78% were found at age group between 15-35 years, 81.7% of them were female and 18.3% were male. More than half of participants 56% had less than four times of weight loss attempts, while 43.6% of them had more than four attempts. The repetition of weight loss attempts was associated with genetic, binge eating, tension, anxiety, negative body image, duration of weight loss maintenance, watching TV or online hours, and eating rate. Around half of participant 55.6% had less than one of successful attempts, while 44.3% had more than one attempts. The factors associated with the successful attempt of weight loss were using weight loss medications, the rate of weight loss, aware food serving, eating breakfast, and exercise. The higher number of attempts of weight lose was associated with higher successful attempt (more than one attempt) P=(0.031). Conclusions: Psychological factors were the most factors affected on repeating weight loss attempts followed by behavior related factors. Practices related to self-control, mental control, stress reduction, and behavior modification should be considered at any weight loss management program. Body weight loss programs need strike follow up by dietician in order to avoid the fluctuations in body weight. Key words: The factors weight loss, weight loss attempts, successful weight loss attempts, weight loss maintenance.

Effects of corn processing and cattle size on total tract digestion and energy and nitrogen balance

This study used 18 calves (295 ± 29 kg) and 18 yearlings (521 ± 29 kg) fed whole, cracked or steam-flaked corn (SFC) to evaluate nutrient digestion and energy balance across different types of processed corn and sizes of cattle. Cattle were fed a diet comprised of 75% corn (DM-basis) from whole, cracked or SFC to 2.5-times maintenance energy requirements. Subsequently, cattle were placed in individual stanchions and urine and feces was collected together with measures of gas production via indirect calorimetry. Data were analyzed using the MIXED procedure of SAS. There was no interaction of corn processing and cattle size (P ≥ 0.40). Time spent ruminating (min/d) and rumination rate (min/kg DM intake; DMI) was not affected by corn processing or cattle size. Eating rate (min/kg DMI) was faster (P < 0.01) for yearlings compared to calves. Total tract starch digestion was greatest (P = 0.01) for cattle fed SFC (97.5%), intermediate in cattle fed cracked (92.4%) and least in cattle fed whole corn (89.5%). Dietary digestible energy and metabolizable energy (Mcal/kg DMI) were greater (P ≤ 0.05) for cattle fed SFC compared to cracked or whole. A greater proportion of digestible energy was lost to heat production (P = 0.01) in cattle fed whole corn compared to cracked and tended to be greater (P = 0.08) in cattle fed SFC than cracked. Conversion of digestible energy to metabolizable energy in this study was more closely related to a dynamic model used to estimate metabolizable energy of feeds to dairy cows than to a linear model used to predict metabolizable energy of feeds to beef cattle. If library estimates of net energy for maintenance are correct, then retained energy (Mcal/d) should have been similar between each type of processed corn; however, retained energy was greater (P < 0.01) for cattle fed cracked compared to whole corn and tended to be greater (P = 0.06) compared to SFC. Yet, observed amounts of net energy based on measures of retained energy were not different (P ≥ 0.60) between cracked and SFC. Nitrogen balance was not affected (P ≥ 0.30) by corn processing or cattle size, although cattle fed cracked had numerically greater (P ≤ 035) N retention. These data indicate that physical processing of corn provides greater net energy to cattle in comparison to whole corn.

311 Effects of Interactive Activity at the Feedbunk on Performance, Feed Efficiency and Feeding Patterns in Feedlot Cattle

The objective of this study was to determine if the magnitude of interactive feeding activity at the feedbunk affects feed efficiency and feeding behavior patterns in beef cattle. This study used data from 498 crossbred steers (3 trials) fed high-concentrate diets in pens with electronic feed bunks (GrowSafe Systems). Timestamp data for bunk visit (BV) events were used to develop an algorithm to quantify those BV events deemed to be replacement events; Defined as those that occur when an animal displaces and replaces another animal from the feedbunk within a specified period of time (replacement criterion). For this study, a replacement criterion of ≤ 18 s was used. A replacement activity index (RAI) was computed for each steer as the number of replacement events divided by total BV events. Within pen, steers were classified into 1 of 3 phenotypes based on ± 0.5 SD from mean RAI. Steers with high RAI (> 0.5 SD from mean RAI) were hypothesized to be more interactive at the feedbunk, whereas steers with low RAI were less interactive at the feedbunk. A mixed model with RAI class as fixed effect, and trial and pen within trial as random effects was used for data analysis. The low RAI steers had 6% fewer BV events that were 12% longer (P < 0.001) in duration than high RAI steers. Additionally, eating rate (g/min) was 14% slower (P < 0.001) and time to approach the feedbunk following feed delivery 6 min longer (P < 0.001) in low vs high RAI steers. The low-RAI steers had substantially less (P < 0.01) feeding activity during peak feeding time than high RAI. Further research is warranted to evaluate interactive feeding activity at the feedbunk as a potential indicator of performance and feed efficiency in feedlot cattle.

335 Evaluation of Hempseed Cake on Cattle Performance, Carcass Characteristics and Feeding Behavior in Finishing Diets

As cannabinoid production continues to increase, there is increasing interest in feeding byproducts of industrial hemp production to livestock. An experiment using crossbred heifers (n = 31; initial BW= 494 kg, SE = 10) was conducted to determine the effects of feeding hempseed cake in a corn-based finishing diet (10% forage) formulated to meet or exceed ruminally degradable and metabolizable protein requirements on growth, performance, carcass characteristics, and feeding behavior. Heifers were assigned randomly to one of two treatments: 1.) diet containing 20% dried distillers grains plus solubles (CON, n = 16), or 2.) diet containing 20% hempseed cake (HEMP, n = 15) on a dry-matter basis. Cattle were housed in two pens, had ad-libitum access to feed and water, and individual intakes and feeding behavior were captured using the Insentec BV feeding system across the feeding period (111 d). Final BW was not different (P = 0.28) between CON (696 kg, SE = 12) and HEMP (683 kg, SE = 12) heifers. Dry matter intake was not different between treatments (P = 0.99), while CON cattle had improved ADG and feed efficiency (G:F; P ≤ 0.04) compared to HEMP cattle. Carcass characteristics were not different (P ≥ 0.20) between treatments for all parameters measured. Control and HEMP cattle were not different (P ≥ 0.34) for number of meals, time spent eating, number of visits to the bunk per day, meal size, or eating rate. Feeding hempseed cake reduced ADG and G:F while having no effect on other performance measures, carcass characteristics, or feeding behavior. Overall, these data suggest hempseed cake could be a viable alternative feed source for ruminants depending on availability and cost. Further understanding of hempseed cakes’ nutrient utilization is critical to determining this products viability as a feedstuff for cattle.

The effects of feeding benzoic acid and/or live active yeast (Saccharomyces cerevisiae) on beef cattle performance, feeding behaviour, and carcass characteristics

Fifty-nine Angus-cross finishing steers were used to evaluate benzoic acid, active dry yeast (Saccharomyces cerevisiae), or a combination of benzoic acid and active dry yeast when supplemented in a high-grain finishing diet on live animal performance, feeding behaviour, and carcass characteristics. Steers were fed a high-grain diet for the final 106 d of finishing. Treatments were; no additional supplementation (CON), 0.5% benzoic acid (ACD), 3 grams per head per day active dry S. cerevisiae (YST), or both 0.5% benzoic acid and 3 grams/head per day S. cerevisiae (AY). Steers were weighed every 14 d, and ultrasound was performed for rib and rump fat thickness at the beginning (d 1), middle (d 57), and end (d 99) of the experiment. Insert feeding stations were used to collect individual feeding behaviour data and DMI daily throughout. Blood samples were collected on d 21-22 and d 99-101 to assess plane of nutrition and metabolism. Ruminal fluid samples were collected by oral gavage 4 weeks prior to slaughter. Carcass characteristics were examined at a federally inspected slaughter facility. Data were analyzed using PROC GLIMMIX of SAS with initial body weight (BW) as a covariate. Benzoic acid supplementation increased (P = 0.002) overall dry matter intake (DMI) compared to YST and CON steers, which may be due to a faster eating rate (P ≤ 0.008). Animal performance parameters (BW, average daily gain, feed conversion, and ultrasound fat depth) were not different (P ≥ 0.11) among treatment groups. Aspartate aminotransferase concentration was greatest (P ≤ 0.01) for YST steers, which may have been reflected in numerically greater liver abscesses. Carcass traits did not differ (P ≥ 0.33) among treatment groups. Ruminal pH was greater (P = 0.006) for ACD steers than AY steers (pH of 6.16 vs. 5.66, respectively), which indicated that there may be an interactive effect between benzoic acid and active dry yeast. To summarize, steers fed a high-grain finishing diet supplemented with benzoic acid, active dry yeast, or both benzoic acid and active dry yeast had similar growth performance and carcass characteristics compared to those without supplementation. However, the addition of benzoic acid alone increased DMI, variation in DMI, eating rate, and ruminal pH. Future studies are warranted to further investigate the impacts of benzoic acid on the ruminal environment of feedlot cattle

Relationship between Personality Traits and Eating speed - Results from a large cross-sectional study among Iranian adults

The eating speed has been hypothesized to be associated with energy intake and weight control. Recently, the effects of some factors on eating rate were investigated, however; studies about the impacts of psychological factors in this field are rare. One of these possible factors is personality traits. This study aimed to assess the relationship between personality traits and eating speed. This cross-sectional study was performed among 4763 adults in 2011. Personality trait was assessed by using the Big Five Personality Inventory Short Form. The eating speed was evaluated using a pretested questionnaire and latent class analysis (LCA) was applied to categorize participants according to the eating speed. Multiple binary logistic regression analysis was used for data analyses. We found that the higher levels of neuroticism (quartile 4) were associated significantly with lower odds of normal eating speed (OR: 0.43; 95% CI: 0.31, 0.60; P<0.001) but higher levels of other personality traits were statistically significantly associated with higher odds of normal eating speed. The current study showed significant associations between personality traits and eating speed; accordingly, it provides primary evidence about the potential value of personality traits for managing the eating rate. Further prospective observational and interventional studies are recommended.

Relationship Between Personality Traits and Eating Speed - Results from a Large Cross-Sectional Study Among Iranian Adults

BackgroundThe eating speed has been hypothesized to be associated with energy intake and weight control. Recently, the effects of some factors on eating rate were investigated, however; studies about the impacts of psychological factors in this field are rare. One of these possible factors is personality traits. This study aimed to assess the relationship between personality traits and eating speed. MethodsThis cross-sectional study was performed among 4763 adults in 2011. Personality trait was assessed by using the Big Five Personality Inventory Short Form. The eating speed was evaluated using a pretested questionnaire and latent class analysis (LCA) was applied to categorize participants according to the eating speed. Multiple binary logistic regression analysis was used for data analyses. ResultsWe found that the higher levels of neuroticism (quartile 4) were associated significantly with lower odds of normal eating speed (OR: 0.43; 95% CI: 0.31, 0.60; P<0.001) but higher levels of other personality traits were statistically significantly associated with higher odds of normal eating speed. ConclusionsThe current study showed significant associations between personality traits and eating speed; accordingly, it provides primary evidence about the potential value of personality traits for managing the eating rate. Further prospective observational and interventional studies are recommended.

Do Behaviors Such As Eating Faster or Taking Larger Bites Moderate the Portion Size Effect?

Objectives Individuals eat more when served larger portions, and this may be influenced by eating-related microstructural behaviors. In a controlled study, we explored whether microstructural components of eating such as eating rate, bite size, bite count, and meal duration influenced the portion size effect. Methods In a randomized crossover design, 44 adults aged 18 to 68 y (66% women; 45% with overweight or obesity) ate lunch in the laboratory once a week for four weeks. The meal consisted of a single dish of pasta (1.4 kcal/g) that was varied in portion size (400,500, 600, or 700 g) along with ∼700 g of water. Intake was assessed by weighing items before and after the meal. To characterize eating microstructure, meals were video-recorded to assess bite counts and meal duration, which were used to calculate mean eating rate (g/min) and mean bite size (g/bite). The influence of eating microstructure on the portion size effect was analyzed by random coefficients models. Results As larger portions were served, meal intake increased in a curvilinear manner (P &lt; 0.0001). Compared to the smallest portion, intake of the largest portion increased by a mean (±SEM) of 123 ± 16 g (43%). As portions were increased, there were similar increases in bite count (35%) and meal duration (38%; both P &lt; 0.0001), but only small increases in mean bite size (8%; P = 0.019) and no significant change in eating rate (P = 0.92). Measures of eating microstructure did not moderate the portion size effect but did have main effects on intake across all portions. Individuals ate more at the meal when they ate faster, took larger bites, took more bites, or ate for longer (all P &lt; 0.0001). Body mass index did not influence eating microstructure or the strength of the portion size effect but had a modest negative effect on intake across all meals (−5.9 ± 2.7 g/unit increase in BMI; P = 0.046). Conclusions Eating-related microstructural behaviors influenced meal intake across portions, but did not moderate the effect of portion size on intake. Individuals who ate faster and took larger bites ate more across all portions, possibly as a result of reduced oro-sensory exposure, which can delay meal termination. Targeted interventions to alter components of eating microstructure have the potential as strategies to reduce overconsumption. Funding Sources NIDDK, Jenny Craig.