Food preferences and weight change during low-fat and low-carbohydrate diets.

UNLABELLED: Understanding associations between food preferences and weight loss during various effective diets could inform efforts to personalize dietary recommendations and provide insight into weight loss mechanisms. We conducted a secondary analysis of data from a clinical trial in which participants were randomized to either a 'choice' arm, in which they were allowed to select between a low-fat diet (n = 44) or low-carbohydrate diet (n = 61), or to a 'no choice' arm, in which they were randomly assigned to a low-fat diet (n = 49) or low-carbohydrate diet (n = 53). All participants were provided 48 weeks of lifestyle counseling. Food preferences were measured at baseline and every 12 weeks thereafter with the Geiselman Food Preference Questionnaire. Participants were 73% male and 51% African American, with a mean age of 55. Baseline food preferences, including congruency of food preferences with diet, were not associated with weight outcomes. In the low-fat diet group, no associations were found between changes in food preferences and weight over time. In the low-carbohydrate diet group, increased preference for low-carbohydrate diet congruent foods from baseline to 12 weeks was associated with weight loss from 12 to 24 weeks. Additionally, weight loss from baseline to 12 weeks was associated with increased preference for low-carbohydrate diet congruent foods from 12 to 24 weeks. Results suggest that basing selection of low-carbohydrate diet or low-fat diet on food preferences is unlikely to influence weight loss. Congruency of food preferences and weight loss may influence each other early during a low-carbohydrate diet but not low-fat diet, possibly due to different features of these diets. CLINICAL TRIAL REGISTRY: NCT01152359.

Effect of Allowing Choice of Diet on Weight Loss: A Randomized Trial.

BACKGROUND: Choosing a diet rather than being prescribed one could improve weight loss. OBJECTIVE: To examine whether offering choice of diet improves weight loss. DESIGN: Double-randomized preference trial of choice between 2 diets (choice) versus random assignment to a diet (comparator) over 48 weeks. (ClinicalTrials.gov: NCT01152359). SETTING: Outpatient clinic at a Veterans Affairs medical center. PATIENTS: Outpatients with a body mass index of at least 30 kg/m2. INTERVENTION: Choice participants received information about their food preferences and 2 diet options (low-carbohydrate diet [LCD] or low-fat diet [LFD]) before choosing and were allowed to switch diets at 12 weeks. Comparator participants were randomly assigned to 1 diet for 48 weeks. Both groups received group and telephone counseling for 48 weeks. MEASUREMENTS: The primary outcome was weight at 48 weeks. RESULTS: Of 105 choice participants, 61 (58%) chose the LCD and 44 (42%) chose the LFD; 5 (3 on the LCD and 2 on the LFD) switched diets at 12 weeks, and 87 (83%) completed measurements at 48 weeks. Of 102 comparator participants, 53 (52%) were randomly assigned to the LCD and 49 (48%) were assigned to the LFD; 88 (86%) completed measurements. At 48 weeks, estimated mean weight loss was 5.7 kg (95% CI, 4.3 to 7.0 kg) in the choice group and 6.7 kg (CI, 5.4 to 8.0 kg) in the comparator group (mean difference, -1.1 kg [CI, -2.9 to 0.8 kg]; P = 0.26). Secondary outcomes of dietary adherence, physical activity, and weight-related quality of life were similar between groups at 48 weeks. LIMITATIONS: Only 2 diet options were provided. Results from this sample of older veterans might not be generalizable to other populations. CONCLUSION: Contrary to expectations, the opportunity to choose a diet did not improve weight loss.

Factors associated with choice of a low-fat or low-carbohydrate diet during a behavioral weight loss intervention.

Individuals undertaking a weight loss effort have a choice among proven dietary approaches. Factors contributing to choice of either a low-fat/low-calorie diet or a low-carbohydrate diet, two of the most studied and popular dietary approaches, are unknown. The current study used data from participants randomized to the 'choice' arm of a trial examining whether being able to choose a diet regimen yields higher weight loss than being randomly assigned to a diet. At study entry, participants attended a group session during which they were provided tailored feedback indicating which diet was most consistent with their food preferences using the Geiselman Food Preference Questionnaire (FPQ), information about both diets, and example meals for each diet. One week later, they indicated which diet they chose to follow during the 48-week study, with the option of switching diets after 12 weeks. Of 105 choice arm participants, 44 (42%) chose the low-fat/low-calorie diet and 61 (58%) chose the low-carbohydrate diet. In bivariate analyses, diet choice was not associated with age, race, sex, education, BMI, or diabetes (all p > 0.05). Low-carbohydrate diet choice was associated with baseline higher percent fat intake (p = 0.007), lower percent carbohydrate intake (p = 0.02), and food preferences consistent with a low-carbohydrate diet according to FPQ (p < 0.0001). In a multivariable logistic regression model, only FPQ diet preference was associated with diet choice (p = 0.001). Reported reasons for diet choice were generally similar for those choosing either diet; however, concerns about negative health effects of the unselected diet was rated as more influential among participants selecting the low-fat diet. Only three low-carbohydrate and two low-fat diet participants switched diets at 12 weeks. Results suggest that when provided a choice between two popular weight loss dietary approaches, an individual's selection is likely influenced by baseline dietary intake pattern, and especially by his or her dietary preferences. Research is needed to determine if congruency between food preferences and dietary approach is associated with weight loss.

Food cravings and food cue responding across the menstrual cycle in a non-eating disordered sample.

The study aim was to examine changes in food cue-elicited cravings and the macronutrient content of craved foods across menstrual cycle phases in a non-eating disordered sample. Thirty-five college females attended laboratory sessions in the late follicular and late luteal phases. In each session they completed a measure of state food craving before and after exposure to preferred, high fat/high sugar chocolate candy. Candy consumption following cue exposure was measured during an ad libitum "taste test." Additionally, participants rated their desire to eat foods differing systematically and significantly in macronutrient content. Ovulation was confirmed with luteinizing hormone detection kits. Results show that whereas the food cue increased cravings, this effect did not differ between cycle phases examined. The macronutrient content of foods desired also did not differ significantly between cycle phases, however, a non-significant trend suggested that high fat/high complex carbohydrate and low fat/high protein foods were more strongly desired in the late luteal phase. Amount of chocolate candy eaten did not differ between cycle phases. These results suggest that cravings for high fat/high sugar foods do not differ between menstrual cycle phases examined, whereas cravings for other foods may fluctuate across cycle phases in non-eating disordered women.

Intake of caffeine from all sources and reasons for use by college students.

BACKGROUND & AIMS: Caffeine intake in a convenience sample of U.S. college students (N = 1248) was surveyed at five geographically-dispersed United States (U.S.) universities. METHODS: Intake from coffee, tea, soft drinks, energy drinks, gums, and medications was assessed. Associations between caffeine intake and demographic variables including sex, age, race/ethnicity, family income, general health, exercise, weight variables and tobacco use were examined. Reasons for use of caffeine-containing products were assessed. RESULTS: Caffeine, in any form, was consumed by 92% of students in the past year. Mean daily caffeine consumption for all students, including non-consumers, was 159 mg/d with a mean intake of 173 mg/d among caffeine users. Coffee was the main source of caffeine intake in male (120 mg/d) and female (111 mg/d) consumers. Male and female students consumed 53 vs. 30 mg/d of caffeine in energy drinks, respectively, and 28% consumed energy drinks with alcohol on at least one occasion. Students provided multiple reasons for caffeine use including: to feel awake (79%); enjoy the taste (68%); the social aspects of consumption (39%); improve concentration (31%); increase physical energy (27%); improve mood (18%); and alleviate stress (9%). CONCLUSIONS: As in the general U.S. population, coffee is the primary source of caffeine intake among the college students surveyed. Energy drinks provide less than half of total daily caffeine intake but more than among the general population. Students, especially women, consume somewhat more caffeine than the general population of individuals aged 19-30 y but less than individuals aged 31-50 y.

Reliability and validity of the Personal Wellness Profile (PWP) Questionnaire in African American college women.

BACKGROUND AND PURPOSE: The Personal Wellness Profile (PWP) is a 75-item questionnaire used to assess an individual's level of wellness in clinical and non-clinical settings. Currently, there are no published scientific data regarding the validity and reliability of the PWP. Therefore, this study was designed to assess convergence validity of the PWP using established instruments in which validity has been previously supported and to determine the reliability of the PWP using the test-retest method. METHODS: A correlational design was used with a non-probability convenience sample of 100 African American women, ages 18 to 40 years, enrolled in a university in southern Louisiana. Convergence validity of the PWP was assessed by using the Michigan Alcoholism Screening Test (MAST), Drug Abuse Screening Test (DAST), Geiselman Food Preference Questionnaire II (GFPQ II), Weekly Stress Inventory (WSI), Fagerstrom Test for Nicotine Dependence (FTND), and the 7-Day Physical Activity Recall Questionnaire (PAR) as criteria. RESULTS: The PWP had statistically significant correlations with two of the six subscales of the GFPQ II, and with the WSI, MAST, and FNTD. Findings also suggest that the PWP has moderate to moderately high internal consistency as a whole (r = .77), and that the subscale scores were also reliable over time (r = .52 to .90). CONCLUSIONS: The PWP will be valuable as a valid, standardized, highly portable tool that can be taken into the community and administered to African-Americans and other populations who do not readily have access to treatment, research and health care centers.

Perceptual Characterization of the Macronutrient Picture System (MaPS) for Food Image fMRI.

Food image fMRI paradigms are used widely for investigating the neural basis of ingestive behavior. However, these paradigms have not been validated in terms of ingestive behavior constructs, engagement of food-relevant neural systems, or test-retest reliability, making the generalizability of study findings unclear. Therefore, we validated the Macronutrient Picture System (MaPS) (McClernon et al., 2013), which includes food images from the six categories represented in the Geiselman Food Preference Questionnaire (FPQ) (Geiselman et al., 1998). Twenty-five healthy young adults (n = 21 female, mean age = 20.6 ± 1.1 years, mean BMI = 22.1 ± 1.9 kg/m2) rated the MaPS images in terms of visual interest, appetitive quality, nutrition, emotional valence, liking, and frequency of consumption, and completed the FPQ. In a second study, 12 individuals (n=8 female, mean age = 25.0 ± 6.5 years, mean BMI = 28.2 ± 8.7 kg/m2) viewed MaPS and control images (vegetables and non-food) during two separate 3T BOLD fMRI scans after fasting overnight. Intuitively, high fat/high sugar (HF/HS) and high fat/high complex carbohydrate (HF/HCCHO) images achieved higher liking and appetitive ratings, and lower nutrition ratings, than low fat/low complex carbohydrate/high protein (LF/LCHO/HP) images on average. Within each food category, FPQ scores correlated strongly with MaPS image liking ratings (p < 0.001). Brain activation differences between viewing images of HF/HS and vegetables, and between HF/HCCHO and vegetables, were seen in several reward-related brain regions (e.g., putamen, insula, and medial frontal gyrus). Intra-individual, inter-scan agreement in a summary measure of brain activation differences in seven reward network regions of interest was high (ICC = 0.61), and was even higher when two distinct sets of food images with matching visual ratings were shown in the two scans (ICC = 0.74). These results suggest that the MaPS provides valid representation of food categories and reliably activates food-reward-relevant neural systems.

Smoking cessation for weight-concerned women: group vs. individually tailored, dietary, and weight-control follow-up sessions.

Postcessation weight gain is of concern to many female cigarette smokers. A multidisciplinary treatment combining psychological, dietary, and exercise components followed a 2-week smoking cessation program. Participants were randomly assigned to receive six follow-up relapse prevention sessions (in a group format or in an individually tailored format) directed by trained representatives from clinical psychology, dietary counseling, and exercise physiology. As predicted, abstinence rates were significantly higher among the individually tailored follow-up participants than among those assigned to the group follow-up condition at 3 and 6 months posttreatment. Differences between conditions in postcessation weight gain were not significant. However, the postcessation weight gain that did occur was significantly associated with subsequent smoking relapse in the group follow-up condition only.

Predictors of pretreatment attrition from smoking cessation among pre- and postmenopausal, weight-concerned women.

The present study sought to determine whether postcessation weight gain concerns influenced pretreatment attrition differently for pre- versus postmenopausal women smokers. Participants were pre- and postmenopausal women smokers drawn from two clinical trials for smoking cessation and weight gain prevention [the Smoking Treatment/Obesity Prevention (STOP) studies]. Predictors of attrition from baseline assessment visits prior to entering smoking cessation treatment were identified among these women. Pretreatment attrition was significantly higher among the premenopausal women. The premenopausal women had significantly higher weight concern but lower restraint and disinhibition than the postmenopausal women. Weight concern explained variance in treatment attrition from the programs, while controlling for variables such as Body Mass Index (BMI), smoking rate, number of years smoking, nicotine dependence level, dietary restraint, disinhibition, and hunger, such that the higher the weight concern, the more likely women were to drop out of treatment programs prior to a quitting attempt.

Consistency of food intake over four eating sessions in the laboratory.

OBJECTIVE: The aim of this study was to test the consistency (repeatability) of laboratory measures of food intake, including eating microstructure (cumulative food intake curves), in non-obese humans across four eating sessions, each separated by 1 week. A secondary aim was to test the effect of dietary restraint on the food intake of female participants. METHODS: Mixed model analyses were used to compare average food intake across sessions, and intraclass correlation coefficients (ICC) were employed to compare within subject variability to total variance. High and low restraint females and low restraint males consumed four lunches in a Universal Eating Monitor (UEM) laboratory. The lunches consisted of one type of sandwich (chicken salad sandwich squares) or three types of sandwiches (chicken salad, ham, and turkey sandwich squares) presented in counterbalanced order. RESULTS: Measures of food intake were stable for men and women, regardless of sandwich variety. In females, level of dietary restraint (high vs. low) did not significantly affect food intake. DISCUSSION: The results indicate that eating behavior in the laboratory is sufficiently stable over time to justify evaluation of interventions designed to alter food intake using within subject designs.

Patterns of dietary supplement use among college students.

BACKGROUND & AIMS: Dietary supplements (DS) are popular in many countries but little data are available on their use by sub-populations such as college students. Since students share a variety of characteristics and similar lifestyles, their DS use may differ from the general population. This study assessed DS use, factors associated with DS use, and reasons for use among U.S. college students. METHODS: College students (N = 1248) at 5 U.S. universities were surveyed. Survey questions included descriptive demographics, types and frequency of DS used, reasons for use and money spent on supplements. Supplements were classified using standard criteria. Logistic regression analyses examined relationships between demographic and lifestyle factors and DS use. RESULTS: Sixty-six percent of college students surveyed used DS at least once a week, while 12% consumed 5 or more supplements a week. Forty-two percent used multivitamins/multiminerals, 18% vitamin C, 17% protein/amino acids and 13% calcium at least once a week. Factors associated with supplement use included dietary patterns, exercise, and tobacco use. Students used supplements to promote general health (73%), provide more energy (29%), increase muscle strength (20%), and enhance performance (19%). CONCLUSIONS: College students appear more likely to use DS than the general population and many use multiple types of supplements weekly. Habits established at a young age persist throughout life. Therefore, longitudinal research should be conducted to determine whether patterns of DS use established early in adulthood are maintained throughout life. Adequate scientific justification for widespread use of DS in healthy, young populations is lacking.

Short-term pilot study of the effect of sleeve gastrectomy on food preference.

The effect of vertical sleeve gastrectomy (VSG) on food preference has not been examined in humans, but VSG decreases preference for fat and calorically dense foods in rodents. A validated Food Preference Questionnaire (FPQ) assessed food preference changes before and 6 weeks after VSG in humans. The FPQ was completed before and 43 ± 19 days (Mean ± SD) after VSG. Fifteen subjects (14 females) completed the study. Hedonic ratings decreased for foods high in fat and sugar (p = 0.002) and high in fat and complex carbohydrate (p = 0.007). Fat preference (p = 0.048) decreased, VSG reduced preference for calorically dense foods high in fat, sugar, and complex carbohydrate, and these changes may contribute to the weight loss with VSG.

Smoking relapse and weight gain prevention program for postmenopausal weight-concerned women: A pilot study.

OBJECTIVE: Postmenopausal women have substantial concerns about weight gain when quitting smoking, which may contribute smoking relapse. There is a need for smoking cessation and weight gain prevention programs effective in this population. METHODS: Two formats of a smoking cessation/weight gain prevention follow-up intervention in postmenopausal weight concerned women were compared: a minimally-tailored group format and a highly tailored, multidisciplinary individual format. Effects on sustained abstinence and postcessation weight gain were assessed. Postmenopausal smokers received 6 sessions of behavioral counseling over a 2-week period, 8weeks of the nicotine transdermal patch, and subsequent random assignment to receive follow-up relapse prevention sessions at 1, 3, 8, and 16weeks postcessation in either group or individual format. RESULTS: The sample (N=98) was 67% Caucasian and 33% African-American. Age: m=52.3 (7.8) years, follicle stimulating hormone: m=42.6 (25.7), body mass index (BMI): m=27.4 (6.2), daily smoking rate: m=20.3 (11.5), for m=29.4 (10.7) years, Fagerström Test for Nicotine Dependence (FTND): m=6.4 (2.1), and carbon monoxide: m=23.8 (13.0) ppm. Abstinence rates in the group condition were significantly higher at 8weeks posttreatment. Group format significantly predicted abstinence rates at 8 and 16weeks posttreatment, even while controlling for age, race, BMI, CPD, years smoking, FTND, and weight concern. Weight concern predicted postcessation weight gain at 8 and 16weeks posttreatment. CONCLUSIONS: Results indicate that smoking cessation programs for postmenopausal women may best be delivered in a group format and that postcessation weight concerns be dealt with prior to a quit date.

Differences in short-term food preferences following vertical sleeve gastrectomy and Roux-en-Y gastric bypass surgery.

Bariatric surgery is effective in reducing body weight and obesity-related comorbidities. This study examined differences in the short-term effect of Roux en Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) on the hedonic rating of food. Predominantly black women with complicated obesity and a BMI>50 g/m(2) completed a validated food preference questionnaire before and 1-3 months following surgery. Analysis of preference scores indicated that the preference for fat decreased with both surgeries. VSG also decreased the preference for sugar. Further studies are needed to evaluate long term effects of surgery on food preferences and to elucidate physiological mechanisms.

Considering patient diet preference to optimize weight loss: design considerations of a randomized trial investigating the impact of choice.

A variety of diet approaches achieve moderate weight loss in many individuals. Yet, most diet interventions fail to achieve meaningful weight loss in more than a few individuals, likely due to inadequate adherence to the diet. It is widely conjectured that targeting the diet to an individual's food preferences will enhance adherence, thereby improving weight loss. This article describes the design considerations of a study protocol aimed at testing this hypothesis. The study is a 2-arm randomized trial recruiting 216 medical outpatients with BMI ≥30 kg/m(2) followed for 48 weeks. Participants in the experimental arm (Choice) select from two of the most widely studied diets for weight loss, a low-carbohydrate, calorie-unrestricted diet (LCD) or a low-fat, reduced-calorie diet (LFD). The participant's choice is informed by results from a validated food preference questionnaire and a discussion of diet options with trained personnel. Choice participants are given the option to switch to the other diet after three months, if desired. Participants in the Control arm are randomly assigned to follow one of the two diets for the duration of follow-up. The primary outcome is weight assessed every 2-4 weeks for 48 weeks. Secondary outcomes include adherence to diet by food frequency questionnaire and obesity-specific health-related quality of life. If assisting patients to choose their diet enhances adherence and increases weight loss, the results will support the provision of diet options to patients who desire weight loss, and bring us one step closer to remediating the obesity epidemic faced by our healthcare systems.

Eating disorder pathology and menstrual cycle fluctuations in eating variables in oral contraceptive users and non-users.

Food intake and food cravings fluctuate across the menstrual cycle in women who are not using oral contraceptives (OCs), however less is known about cyclical variations in eating variables in women using OCs. Furthermore, few studies have examined the relationship between eating disorder pathology and menstrual cycle fluctuations in eating behaviors. In the present study, we examined self-report, retrospective ratings of food cravings intensity, hunger level, and amount eaten across the menstrual cycle in 67 non-OC users and across exogenous hormone regimens in 81 OC users. We also investigated the relationship between eating disorder pathology and cyclical fluctuations in eating variables. The results indicated that OC users and non-OC users report similar levels of food cravings and amount eaten across cycle phases, with food cravings and reported amount eaten elevated during the week prior to menses/hormone withdrawal bleeding and during the week of menses/hormone withdrawal bleeding. However, OC users reported elevated hunger during both the week prior to hormone withdrawal bleeding and during hormone withdrawal bleeding, whereas non-OC users reported an elevation in hunger level only during the week prior to menses. Fear of fatness and other eating disorder pathology variables were significantly associated with increases in food cravings, hunger level and reported amount eaten the week prior to menses in non-OC users, but not in OC users. These findings suggest that future studies should examine the potential role of menstrual cycle-related fluctuations in eating variables on the development of eating disorders.

Change in food cravings, food preferences, and appetite during a low-carbohydrate and low-fat diet.

The study objective was to evaluate the effect of prescribing a low-carbohydrate diet (LCD) and a low-fat diet (LFD) on food cravings, food preferences, and appetite. Obese adults were randomly assigned to a LCD (n = 134) or a LFD (n = 136) for 2 years. Cravings for specific types of foods (sweets, high-fats, fast-food fats, and carbohydrates/starches); preferences for high-sugar, high-carbohydrate, and low-carbohydrate/high-protein foods; and appetite were measured during the trial and evaluated during this secondary analysis of trial data. Differences between the LCD and LFD on change in outcome variables were examined with mixed linear models. Compared to the LFD, the LCD had significantly larger decreases in cravings for carbohydrates/starches and preferences for high-carbohydrate and high-sugar foods. The LCD group reported being less bothered by hunger compared to the LFD group. Compared to the LCD group, the LFD group had significantly larger decreases in cravings for high-fat foods and preference for low-carbohydrate/high-protein foods. Men had larger decreases in appetite ratings compared to women. Prescription of diets that promoted restriction of specific types of foods resulted in decreased cravings and preferences for the foods that were targeted for restriction. The results also indicate that the LCD group was less bothered by hunger compared to the LFD group and that men had larger reductions in appetite compared to women.

Cardiovascular risk in African American women attending historically Black colleges and universities: the role of dietary patterns and food preferences.

There is a lack of data on the dietary patterns and food preferences of African American women attending historically Black colleges and universities (HBCUs). African American women have higher death rates from cardiovascular disease than White women, and the initiating events of cardiovascular disease often begin in young adulthood. The purpose of this study was to identify the dietary patterns and food preferences of African American college women, which may act as risk factors for cardiovascular disease. A convenience sample of 100 African American women, ages 18 to 40 years, was administered two surveys assessing food preferences and dietary patterns. The majority of the participants (65%) preferred high-fat foods, and most of the participants (87%) consumed more than 30% of their daily caloric intake from fat. There is a definite need for dietary education regarding the impact of dietary fat on cardiovascular health among college students.

Effects of consuming mycoprotein, tofu or chicken upon subsequent eating behaviour, hunger and safety.

This study tested if: (1) a preload of mycoprotein and tofu consumed before a lunch meal have a greater effect on satiety when compared to a chicken preload, (2) the mycoprotein and tofu preloads, compared to chicken, are not associated with compensation or eating more food at a subsequent dinner meal. These hypotheses were tested in a controlled laboratory study using universal eating monitors to measure food intake and visual analogue scales to monitor hunger and satiety. Forty-two overweight adult females consumed three meals in the laboratory on 3 test days. At lunch, isocaloric pasta preloads, containing mycoprotein, tofu, or chicken, varied across the days in a balanced order. The findings of the study supported the two hypotheses. Mycoprotein and tofu preloads, in comparison to the chicken preload, were associated with lower food intake shortly after consuming the preload at lunch. Food intake following consumption of mycoprotein and tofu did not differ, and participants did not compensate for lower food intake at lunch by consuming more food at dinner. The findings suggest that mycoprotein and tofu have satiating properties that persist for several hours after a meal. These findings have significant implications for the development of foods that are low in kilojoules, but are also filling.