Effects of a meal replacement system alone or in combination with phentermine on weight loss and food cravings.

OBJECTIVE: To examine the effects of phentermine combined with a meal replacement program on weight loss and food cravings and to investigate the relationship between food cravings and weight loss. METHODS: In a 12-week randomized, double-blind, placebo-controlled clinical trial, 77 adults with obesity received either phentermine or placebo. All participants were provided Medifast® meal replacements, were instructed to follow the Take Shape for Life® Optimal Weight 5&1 Plan for weight loss, and received lifestyle coaching in the Habits of Health program. The Food Craving Inventory and the General Food Cravings State and Trait Questionnaires were used to measure food cravings. RESULTS: The phentermine group lost 12.1% of baseline body weight compared with 8.8% in the placebo group. Cravings for all food groups decreased in both groups; however, there was a greater reduction in cravings for fats and sweets in the phentermine group compared with the placebo group. Percent weight loss correlated significantly with reduced total food cravings (r = 0.332, P = 0.009), cravings for sweets (r = 0.412, P < 0.000), and state food cravings (r = 0.320, P = 0.007). CONCLUSIONS: Both phentermine combined with a meal replacement program and meal replacements alone significantly reduced body weight and food cravings; however, the addition of phentermine enhanced these effects.

Interaction between infectious diseases and personality traits: ACP1*C as a potential mediator.

In geographical regions characterized by high pathogen prevalence, it has been shown that human populations tend to be characterized by lower levels of extraversion (E) and openness to experience (OtE). According to the "behavioral immune system" hypothesis, the reduction of extraversion and openness levels represents a behavioral defense against infections. Like the 'classical' immune system, the "behavioral immune system" could also be shaped by its underlying genetic background. Previous studies have shown that the *C allele of the ACP1 gene confers increased susceptibility to infectious/parasitic diseases. We hypothesized that carriers of the ACP1*C allele should likewise be associated with reduced E and OtE. We tested this hypothesis using two samples comprised of 153 students from Southern California (Group 1), and 162 female subjects recruited from an executive health program (Group 2), genotyped for ACP1 polymorphism and evaluated by the NEO Five-Factor Inventory (NEO-FFI). ACP1 was significantly associated with E: we found that carriers of ACP1*C showed reduced scores for E (Group 1: ß=-4.263, P=0.027; Group 2: ß=-8.315, P=0.003; Group 1+Group 2: ß=-5.366, P=0.001). Across groups, ACP1 was only marginally associated with OtE. In conclusion, the present study found that the ACP1*C allele, previously associated with an increased vulnerability to infectious/parasitic diseases may also be able to shape behavioral immune defenses by interaction with the level of E.

Phenylethanolamine N-methyltransferase G-148A genetic variant and weight loss in obese women.

OBJECTIVE: To understand the impact of the phenylethanolamine N-methyltransferase (PNMT) G-148A gene and nutritional variables on weight loss in obese women. RESEARCH METHODS AND PROCEDURES: One hundred forty-nine women, ages 45 to 65 with a body mass index of >30 kg/m(2), participated in a 6-month, open-label intervention that included sibutramine (15 mg/d) and a monthly health-education class. Anthropometric measurements, vital signs, food frequency, exercise log, medication compliance, and psychological and sociological questionnaires were completed each month. Genetic polymorphisms of PNMT were determined. RESULTS: Univariate analysis of G/G, G/A, and A/A genotypes against tertiles of percentage of weight loss were significant at 3 but not at 6 months (Pearson chi(2): p < 0.006; homozygous/heterozygosity: p < 0.002, p < 0.253, and p < 0.122, respectively). A regression model that included the PNMT genetic variation and certain nutrition and exercise variables demonstrated that only the PNMT gene (beta = 0.360, SE 0.585, and p = 0.003) was statistically significant at 6 months, and the total calories (beta = -0.925, SE = 0.004, and p = 0.009), fiber intake (beta = 0.621, SE = 0.124, and p = 0.000), and PNMT (beta = 0.262, SE = 1.415, and p = 0.024) were significant. DISCUSSION: The homozygosity/heterozygosity of the PNMT gene was highly predictive of significant weight loss with sibutramine during the first 3 months, which highlights the need for specific pharmacotherapy. The early weight-loss success of those subjects who were homozygous for PNMT may have motivated and selected those that would make further dietary changes, which then augmented their final weight loss.

Association of the acid phosphatase (ACP1) gene with triglyceride levels in obese women.

The acid phosphatase (ACP1) locus codes for a low molecular weight protein tyrosine phosphatase (LMPTP) that is found ubiquitously in human tissues. The *A allele of the ACP1 gene is associated with lower total enzymatic activity than the *B and *C alleles. An association between the *A allele and extreme values of body-mass-index (BMI) and dyslipidemia has previously been described in several samples of obese subjects from the Italian population. In the present study, we investigated the relationship between ACP1 *A allele genotypes (*A/*A, *A/*B, and *A/*C) and non-*A allele genotypes (*B/*B, *B/*C, and *C/*C) and metabolic variables in 277 Caucasian post-menopausal subjects consisting of 82 non-obese subjects (BMI/=35) subjects. ACP1 genotypes were found to be significantly associated with total cholesterol (p

Reproducibility of DXA in obese women.

Dual-energy X-ray absorptiometry (DXA) measurements were analyzed using two versions of software (Hologic V8.1a and V8.21) to compare the short- and long-term precisions of the measurements. Software V8.21 was designed by the manufacturer to better address magnification effects on estimations of soft tissue lean mass. Twenty weight-stable, obese postmenopausal Caucasian women aged 40-70 yr participated in the study. Total and regional body composition measurements were obtained at baseline and after 3 mo, using a fan beam Hologic QDR 4500A absorptiometer. For the estimation of precision, duplicate scans obtained on the same day for nine women were analyzed using both versions of the software. The correlations between duplicate scans ranged from 0.886 to 0.998 and were similar between software versions. The CVs for fat and lean weights and bone mineral content (BMC) were 1.2%, 1.1%, and 1.7%, respectively, for software V8.21 compared to 1.3%, 1.3%, and 2.1%, respectively, for V8.1a. Systematic differences were found between software versions with higher values for fat and lean weights for software version V8.21. The 3-mo, long-term reproducibility of body composition estimates from DXA was only slightly less than short-term reproducibility for both software versions (coefficient of variation [CV] range from 1.3% for BMC weight to 11.0% for arm fat). Software V8.21 yielded smaller percentage mean differences between scale and DXA-estimated weights (-2.4% and -7.2% at baseline and -2.9% and -7.6% at 3 mo, respectively) and higher fat and lean weights (49.12 and 47.1 kg and 49.6 and 44.6 kg, respectively) than V8.1a. Reproducibility of all variables was comparable between software versions.