Effect Of Long-term Diet Research Articles

Exploring the association between dietary Inflammatory Index and chronic pain in US adults using NHANES 1999–2004

Chronic pain, a substantial public health issue, may be influenced by dietary patterns through systemic inflammation. This cross-sectional study explored the association between Dietary Inflammatory Index (DII) and chronic pain among 2581 American adults from NHANES data. The DII, ranging from − 4.98 to 4.69, reflects the inflammatory potential of the diet, with higher scores indicating greater pro-inflammatory capacity. Our findings showed no significant association between the continuous DII score and chronic pain prevalence. However, a nonlinear relationship emerged. When the DII was categorized, a significant association between higher DII scores (DII ≥ 2.5) and chronic pain prevalence was observed. The analysis uncovered a U-shaped pattern, with an inflection point at a DII score of − 0.9, indicating an association between both low and high levels of dietary inflammation are associated with higher pain prevalence. This nuanced interaction between dietary inflammation and chronic pain indicates the possibility of incorporating dietary modification into pain management strategies and underscores the need for further research into the long-term effects of diet on chronic pain.

Nutrition Guidance for Patients on Androgen Deprivation Therapy

Dietary guidance for men with prostate cancer on androgen deprivation therapy (ADT) should focus on reducing the risk of prostate cancer-specific outcomes and other chronic diseases, including cardiovascular disease (CVD). National guidelines for both CVD prevention and cancer survivors recommend a diet rich in fruits and vegetables and low in red/processed meat, refined grains, and added fats and sugars. Additional observational studies and randomized controlled trials are needed to examine short- and long-term effects of diet on clinical, biological, and patient-reported outcomes for men treated with ADT.

Impact of feeding habits on the development of language-specific processing of phonemes in brain: An event-related potentials study.

Infancy is a stage characterized by multiple brain and cognitive changes. In a short time, infants must consolidate a new brain network and develop two important properties for speech comprehension: phonemic normalization and categorical perception. Recent studies have described diet as an essential factor in normal language development, reporting that breastfed infants show an earlier brain maturity and thus a faster cognitive development. Few studies have described a long-term effect of diet on phonological perception. To explore that effect, we compared the event-related potentials (ERPs) collected during an oddball paradigm (frequent /pa/80%, deviant/ba/20%) of infants fed with breast milk (BF), cow-milk-based formula (MF), and soy-based formula (SF), which were assessed at 3, 6, 9, 12, and 24 months of age [Mean across all age groups: 127 BF infants, Mean (M) 39.6 gestation weeks; 121 MF infants, M = 39.16 gestation weeks; 116 SF infants, M = 39.16 gestation weeks]. Behavioral differences between dietary groups in acoustic comprehension were observed at 24-months of age. The BF group displayed greater scores than the MF and SF groups. In phonological discrimination task, the ERPs analyses showed that SF group had an electrophysiological pattern associated with difficulties in phonological-stimulus awareness [mismatch negativity (MMN)-2 latency in frontal left regions of interest (ROI) and longer MMN-2 latency in temporal right ROI] and less brain maturity than BF and MF groups. The SF group displayed more right-lateralized brain recruitment in phonological processing at 12-months old. We conclude that using soy-based formula in a prolonged and frequent manner might trigger a language development different from that observed in the BF or MF groups. The soy-based formula's composition might affect frontal left-brain area development, which is a nodal brain region in phonological-stimuli awareness.

Dietary Antioxidant Capacity and Skin Photoaging: A 15-Year Longitudinal Study

The long-term effect of diet on skin aging is largely unknown, but evidence suggests that the antioxidants from foods may mitigate the main component of skin aging caused by sun exposure. We assessed the association between the total antioxidant capacity of foods people eat and the photoaging of their skin. In a community-based, prospective study among 777 Australian adults aged <55 years at baseline, we estimated the total dietary antioxidant capacity of participants' diets in 1992, 1994, and 1996 and graded photoaging severity using microtopography in 1992, 1996, and 2007. We used ordinal logistic regression and applied generalized estimating equations to estimate change in the degree of photoaging associated with increasing total antioxidant capacity compared with the group with the lowest antioxidant capacity, separately in younger (≤45 years) and older (>45 years) adults. In the 15-year study period, the overall prevalence of severe skin photoaging increased from 42% at baseline to 88%. Adults aged >45 years who consumed foods with high antioxidant capacity experienced approximately 10% less photoaging over 15 years than those who ate foods with low antioxidant capacity. No association was found among adults aged ≤45 years. Foods rich in antioxidants as measured by antioxidant capacity may retard skin aging among healthy men and women aged >45 years.

Effect of kibble and raw meat diets on peripheral blood mononuclear cell gene expression profile in dogs

Peripheral blood mononuclear cell (PBMC) gene expression microarray profiling is a minimally invasive tool used in human diet intervention studies. In this study, PBMC gene expression was determined in dogs fed kibble or raw red meat diets for 9 weeks to test the hypothesis that diet influences canine immune cell gene expression profiles. The two diets were associated with differences in PBMC gene expression profiles, which corresponded with changes in plasma IgA concentrations. Analysis of PBMC gene expression profiles might provide useful insights into the long term effects of diet on health outcomes in dogs.

The Karlsruhe Metabolomics and Nutrition (KarMeN) Study: Protocol and Methods of a Cross-Sectional Study to Characterize the Metabolome of Healthy Men and Women.

BackgroundThe human metabolome is influenced by various intrinsic and extrinsic factors. A precondition to identify such biomarkers is the comprehensive understanding of the composition and variability of the metabolome of healthy humans. Sample handling aspects have an important impact on the composition of the metabolome; therefore, it is crucial for any metabolomics study to standardize protocols on sample collection, preanalytical sample handling, storage, and analytics to keep the nonbiological variability as low as possible.ObjectiveThe main objective of the KarMeN study is to analyze the human metabolome in blood and urine by targeted and untargeted metabolite profiling (gas chromatography-mass spectrometry [GC-MS], GC×GC-MS, liquid chromatography-mass spectrometry [LC-MS/MS], and1H nuclear magnetic resonance [NMR] spectroscopy) and to determine the impact of sex, age, body composition, diet, and physical activity on metabolite profiles of healthy women and men. Here, we report the outline of the study protocol with special regard to all aspects that should be considered in studies applying metabolomics.MethodsHealthy men and women, aged 18 years or older, were recruited. In addition to a number of anthropometric (height, weight, body mass index, waist circumference, body composition), clinical (blood pressure, electrocardiogram, blood and urine clinical chemistry) and functional parameters (lung function, arterial stiffness), resting metabolic rate, physical activity, fitness, and dietary intake were assessed, and 24-hour urine, fasting spot urine, and plasma samples were collected. Standard operating procedures were established for all steps of the study design. Using different analytical techniques (LC-MS, GC×GC-MS,1H NMR spectroscopy), metabolite profiles of urine and plasma were determined. Data will be analyzed using univariate and multivariate as well as predictive modeling methods.ResultsThe project was funded in 2011 and enrollment was carried out between March 2012 and July 2013. A total of 301 volunteers were eligible to participate in the study. Metabolite profiling of plasma and urine samples has been completed and data analysis is currently underway.ConclusionsWe established the KarMeN study applying a broad set of clinical and physiological examinations with a high degree of standardization. Our experimental approach of combining scheduled timing of examinations and sampling with the multiplatform approach (GC×GC-MS, GC-MS, LC-MS/MS, and1H NMR spectroscopy) will enable us to differentiate between current and long-term effects of diet and physical activity on metabolite profiles, while enabling us at the same time to consider confounders such as age and sex in the KarMeN study.Trial RegistrationGerman Clinical Trials Register DRKS00004890; https://drks-neu.uniklinik-freiburg.de/drks_web/navigate.do? navigationId=trial.HTML&TRIAL_ID=DRKS00004890 (Archived by WebCite at http://www.webcitation.org/6iyM8dMtx)

Development and validation of empirical indices of dietary insulinemic potential

The glycemic index and insulin index assess postprandial glycemic and insulin response to foods, respectively, which may not reflect long‐term effects of diet on glycemia or insulinemia. We developed and validated three empirical dietary indices (EDI) to assess the insulinemic potential of usual diet:hyperinsulinemia (EDIH), insulin resistance (EDIR) and both hyperinsulinemia and insulin resistance (CDHR), using dietary and biomarker data from the Nurses’ Health Study (NHS, n=5,986 for EDIH, n=3,988 for EDIR). We entered 39food frequency questionnaire‐derived food groups in stepwise linear regression models and defined the indices as dietary patterns most predictive of C‐peptide(EDIH) and triglycerides/high density lipoprotein‐cholesterol (TG/HDL) ratio (EDIR). The CDHR was derived by combining components of the EDIH and EDIR. Indices were validated in two independent samples from NHS‐II and Health Professionals Follow‐up Study (HPFS) using C‐peptide and TG/HDL as construct validators in multivariable‐adjusted linear regression analyses. The EDIH comprised of 19 food groups;11 were positively and eight were negatively associated with C‐peptide concentrations. The EDIR comprised of 18 food groups; nine positively and nine negatively associated with TG/HDL ratio, while twenty‐six unique food groups comprised the CDHR. In NHS, the Pearson correlation coefficient was 0.22 for EDIH and C‐peptide and 0.31 for EDIR and TG/HDL ratio. Similar correlations were found in HPFS and NHS‐II. In HPFS and NHS‐II, all three indices significantly predicted biomarker concentrations. E.g., comparing extreme index quintiles (Q5/Q1)(95%CI) biomarker concentrations in HPFS were: EDIH, 1.25 (1.18, 1.33), ptrend&lt;0.0001; EDIR, 1.42(1.32, 1.52), ptrend&lt;0.0001;CDHR, 1.26 (1.19, 1.34), ptrend&lt;0.0001for C‐peptide and 1.31 (1.22, 1.41), ptrend&lt;0.0001 for TG/HDL. The strong validity of these novel hypothesis‐driven indices in independent populations suggests their usefulness in assessing the ability of whole diets to stimulate and/or sustain insulin secretion.Support or Funding InformationDrs. Jorge E. Chavarro and Frank B. Hu were supported by National Institutes of Health (NIH) grants P30DK046200 and U54 CA155426. The HPFS, NHS and NHS‐II cohorts are supported by the following NIH grants: UM1 CA 167552, UM1 CA 186107 and UM1 CA 176726 respectively. Mulltivariable‐adjusted11 relative concentrations2 of biomarkers in quintiles of insulinemic dietary patterns in the NHS, HPFS and NHS‐II3 cohorts Quintile1 Quintile 2 Quintile 3 Quintile 4 Quintile 5 4Ptrend Empirical dietary index for hyperinsulinemia (EDIH) C‐peptide (NHS, n=5,986) 1.00 1.11 (1.07, 1.16) 1.20 (1.15, 1.25) 1.25 (1.20, 1.31) 1.42 (1.35, 1.48) &lt;0.0001 C‐peptide (HPFS, n=3,984) 1.00 1.02 (0.97, 1.08) 1.18 (1.11, 1.25) 1.17 (1.11, 1.24) 1.25 (1.18, 1.33) &lt;0.0001 TG/HDL ratio (HPFS, n=3,559) 1.00 1.10 (1.01, 1.16) 1.12 (1.04, 1.20) 1.24 (1.15, 1.33) 1.26 (1.18, 1.36) &lt;0.0001 C‐peptide (NHS‐II, n=1,736) 1.00 1.08 (0.99, 1.18) 1.09 (1.00, 1.19) 1.21 (1.10, 1.32) 1.30 (1.19, 1.43) &lt;0.0001 Empirical dietary index for insulin resistance (EDIR) TG/HDL ratio (NHS, n=3,988) 1.00 1.17 (1.10, 1.25) 1.31 (1.23, 1.40) 1.42 (1.32, 1.52) 1.67 (1.56, 1.79) &lt;0.0001 TG/HDL ratio (HPFS, n=3,559) 1.00 1.17 (1.09, 1.25) 1.21 (1.12, 1.29) 1.38 (1.29, 1.48) 1.42 (1.32, 1.52) &lt;0.0001 C‐peptide (HPFS, n=3,984) 1.00 0.99 (0.93, 1.05) 1.07 (1.01, 1.13) 1.09 (1.03, 1.16) 1.14 (1.07, 1.21) &lt;0.0001 Composite dietary index for hyperinsulinemia and insulin resistance (CDHR) C‐peptide (HPFS, n=3,984) 1.00 1.06 (1.00, 1.12) 1.08 (1.02, 1.15) 1.14 (1.08, 1.21) 1.26 (1.19, 1.34) &lt;0.0001 TG/HDL ratio (HPFS, n=3,539) 1.00 1.10 (1.03, 1.18) 1.14 (1.06, 1.22) 1.23 (1.15, 1.33) 1.31 (1.22, 1.41) &lt;0.0001 Multivariable models were adjusted for regular aspirin/NSAIDs use, age, smoking status, chronic diseases/conditions, case‐control status; in women, models were additionally adjusted for menopausal status and postmenopausal hormone use; relative concentrations are the concentrations of biomarkers in higher dietary density index quintiles divided by the reference quintile (Q1); NHS=Nurses’ Health Study and HPFS=Health Professional Follow‐up Study; the p‐value for trend was the p‐value of the continuous dietary index Variable for the potential confounders listed in footnote #1.

Abstract 48: Long-term Effects of an Intensive Lifestyle Intervention on Electrocardiographic Evidence of Left Ventricular Hypertrophy: The Action for Health in Diabetes (Look AHEAD) Trial

Introduction: Left ventricular hypertrophy assessed by electrocardiography (ECG-LVH) is a marker of subclinical cardiac damage and a strong predictor of cardiovascular events. The prevalence of ECG-LVH is increased in obesity and type 2 diabetes; thus, exercise and weight loss are recommended to lower cardiovascular disease (CVD) risk in these individuals. However, there are no data on the long term effects of diet- and/or exercise-induced weight loss on ECG-LVH. Hypothesis: We hypothesized that an intensive lifestyle intervention targeting weight loss through caloric restriction and increased physical activity reduces the incidence of ECG-LVH in overweight and obese adults with type 2 diabetes. Methods: We included 4,549 Look AHEAD participants without ECG-LVH at baseline who were randomized to a 10-year lifestyle intervention (ILI, n=2,287) or diabetes support and education (DSE, n=2,262) (mean age = 58.7±6.8 years, 64.5% White). ECG-LVH defined by the Cornell voltage criteria (RaVL + SV3 &gt;2800 μV in men and &gt;2000 μV in women) was assessed every 2 years. Proportional hazards regression was used to compare the incidence of ECG-LVH (defined as time to first occurrence) and mixed models were used to compare changes in absolute Cornell voltage over time between intervention groups, with tests of interactions by gender, race/ethnicity and baseline CVD status. Analyses were performed according to the intention-to-treat principle and all available follow-up data were included. Results: Baseline characteristics were similar between intervention groups, except for lower systolic blood pressure in the ILI vs. DSE group: mean (SE) = 127.6 (0.4) mmHg vs. 129.0 (0.4) mmHg, respectively (p=0.007). Over a median 9.5 years of follow-up, there were 162 cases of incident ECG-LVH in the ILI group (7.1%) and 181 cases in the DSE group (8.0%): HR=0.89, 95% CI=0.71-1.09, p=0.24. Intervention group interactions were not significant for prior CVD (p=0.53) or gender (p=0.74), but were of borderline significance for race/ethnicity (p=0.058). Among African Americans, ILI was estimated to be protective relative to DSE (HR=0.59, 95% CI= 0.38-0.91); there was no significant interaction for other race/ethnicity groups. Similar results were found after multivariate adjustment. In the mixed model analysis, the mean (SE) Cornell voltage was slightly lower in the ILI group compared to the DSE group after adjusting for the baseline value, age, gender, race/ethnicity, and prior CVD: 1369.2 (5.4) μV vs. 1381.9 (5.4) μV, respectively (p=0.07). Accounting for changes in blood pressure and anti-hypertensive medication use did not alter the results. Conclusions: A long-term intensive lifestyle intervention in overweight and obese adults with type 2 diabetes does not significantly lower overall incident ECG-LVH. The protective effect observed in African Americans, however, warrants further investigation.

Pharmacokinetic food-effect study of abiraterone acetate (AA) in patients with metastatic castration resistant prostate cancer (mCRPC): The ABIFOOD trial (EudraCt number: 2012-003226-25).

227 Background: A.A has been approved for the treatment of mCRPC before and after docetaxel. The standard regime consists on daily A.A. 1.000 mg in a fasting state along with prednisone 10mg q.d. However, data from pharmacokinetic (PK) studies in patients (pts) and healthy volunteers has revealed a significant food-effect with up to 7-10 folder increase in area under plasma concentration-time curve (AUC) when A.A is given with food, specially with fat content, [Chi KN, J Clin Pharmacol 2015]. Methods: ABIFOOD is a phase I, randomized trial to evaluate the short and long-term effect of diet on the PKs of A.A. in pts with mCRPC who have progressed to docetaxel. Eligible pts include men ≥ 18 years old with mCRPC, ECOG performance status (PS) &lt; 2 and an adequate organ function. Pts are randomly assigned to receive 4-weekly cycles of 250 mg A.A with standard meal (Arm A), 250 mg A.A with high-fat meal (Arm B) or 1000 mg A.A in fasting conditions (Arm C). PK analyses are conducted at week 1 (W1) and cycle 5. Results: Fifteen pts (5, 3 and 7 in arms A, B and C respectively) have been included and 6 are still on treatment. Median age is 72, 97% have ECOG-PS 1. Gleason Score is &gt; 8 in 6 (40%) pts.Geometric mean abiraterone [AUC (ng.h/ml) (IQR)] at W1 did not significantly differ between treatment arms [arm A: 404.68 (368.4 - 488.2), arm B: 372 (334.6 - 440.5) arm C: 656.51 (387.8 – 1144.5) p 0.15]. PK data did not influence activity or toxicity. Progression free survival was 8.50, 6.33 and 4.86 months in Arms A, B and C respectively (p 0.53). One patient in arm A is still on treatment after 17 cycles. Conclusions: The administration of lower doses of A.A with food [regardless the fat content], might achieve comparable plasma levels to standard dosing with no detriment in efficacy or toxicity parameters. The study is actively recruiting and data on additional pts and long term PK parameters will be presented. Clinical trial information: EudraCt number: 2012-003226-25.

The long-term effect of energy restricted diets for treating obesity.

To quantify the effectiveness of diet interventions by systematic review of the long-term effects of energy restricted diets in individuals with overweight and obesity. A systematic literature search was conducted for all clinical trials studying the effect of energy restricted diets on body weight in individuals with a BMI>25 kg/m(2) with a follow-up of at least 3 years and a minimum of 50 participants. Weight change from baseline and rates of loss to follow-up at the longest follow-up were extracted and analyzed using random-effects models. Weighted mean weight loss after 3 years follow-up was 3.5% (95% CI 0.2-6.8%) (n = 6,163) and after 4 years follow-up 4.5% (95% CI 4.3-4.8%) (n = 5,696). Energy restricted diets (n = 1,433) resulted in an average 2.9% (95% CI -3.8 to -2.1%) greater weight loss compared to untreated control groups (n = 1,361). Weight regain was observed in the majority of individuals in all studies. Interpretation of the data is limited by high rates of loss to follow-up and lack of truly untreated control groups. On average, the long-term effect of diets on body weight in individuals with obesity is modest, and the response is highly heterogeneous.

Longevity: epigenetic and biomolecular aspects.

Many aging theories and their related molecular mechanisms have been proposed. Simple model organisms such as yeasts, worms, fruit flies and others have massively contributed to their clarification, and many genes and pathways have been associated with longevity regulation. Among them, insulin/IGF-1 plays a key and evolutionary conserved role. Interestingly, dietary interventions can modulate this pathway. Calorie restriction (CR), intermittent fasting, and protein and amino acid restriction prolong the lifespan of mammals by IGF-1 regulation. However, some recent findings support the hypothesis that the long-term effects of diet also involve epigenetic mechanisms. In this review, we describe the best characterized aging pathways and highlight the role of epigenetics in diet-mediated longevity.

Differentiating short- and long-term effects of diet in the obese mouse using 1H-nuclear magnetic resonance metabolomics

This study determined whether targeted metabolomic profiling of serum, using 1H nuclear magnetic resonance, could be employed to distinguish the effects of obesity from those of diet in mice. Following weaning, littermates were randomly divided into two diet groups: chow and high fat. After 12 weeks of dietary manipulation, fat-fed animals were obese and hyperglycaemic. Mice from each treatment either maintained their current diet or switched to the opposite diet for a final week. Differences in metabolite levels were determined using orthogonal projection to latent structures and cross-validated discriminant analysis. The short- and long-term effects of each diet could be clearly distinguished. Short-term diet effects are the major contributor to the metabolic profile, underscoring the need for controls beyond the standard fast before serum collection. This work shows the importance of dietary controls when attempting to isolate obesity-related changes and highlights the ability of metabolomics to identify subtle changes when experiments are properly structured.

Fructose, Obesity, and Related Epidemiology

Fructose occurs in fruits, vegetable, and sweetened drinks alongside glucose as free sugars or bound in sucrose, but may also be bought in a pure form. A link between sugar-sweetened drinks (SSD) and body mass index (BMI, kg/m2) is inferred from systematic reviews of both prospective cohort studies (PCSs) and randomized, controlled trials (RCTs) (Malik et al., 2006; Wolf and Dansinger, 2008). The link is seemingly strong because such studies rank highly among types of studies according to evidence-based principles on causality. On the other hand, the study results are heterogeneous, and more objective meta-analysis shows SSDs to have a “small” effect on BMI (Forshee et al., 2008); therefore, a focus on fructose and SSD may then serve only to divert attention from major causes of obesity (Storey, 2008). A number of complications and false claims arise when interpreting epidemiological and interventional studies on fructose or SSDs. The first is a notion that high-fructose corn syrup (HFCS) differs from suc...

Surgical treatment of obesity

More than half of the European population are overweight (body mass index (BMI) > 25 and < 30 kg/m2) and up to 30% are obese (BMI > or = 30 kg/m2). Being overweight and obesity are becoming endemic, particularly because of increasing nourishment and a decrease in physical exercise. Insulin resistance, type 2 diabetes, dyslipidemia, hypertension, cholelithiasis, certain forms of cancer, steatosis hepatis, gastroesophageal reflux, obstructive sleep apnea, degenerative joint disease, gout, lower back pain, and polycystic ovary syndrome are all associated with overweight and obesity. The endemic extent of overweight and obesity with its associated comorbidities has led to the development of therapies aimed at weight loss. The long-term effects of diet, exercise, and medical therapy on weight are relatively poor. With respect to durable weight reduction, bariatric surgery is the most effective long-term treatment for obesity with the greatest chances for amelioration and even resolution of obesity-associated complications. Recent evidence shows that bariatric surgery for severe obesity is associated with decreased overall mortality. However, serious complications can occur and therefore a careful selection of patients is of utmost importance. Bariatric surgery should at least be considered for all patients with a BMI of more than 40 kg/m2 and for those with a BMI of more than 35 kg/m2 with concomitant obesity-related conditions after failure of conventional treatment. The importance of weight loss and results of conventional treatment will be discussed first. Currently used operative treatments for obesity and their effectiveness and complications are described. Proposed criteria for bariatric surgery are given. Also, some attention is devoted to more basic insights that bariatric surgery has provided. Finally we deal with unsolved questions and future directions for research.

W16-P-024 Effect of long-term diet and N-3 fatty acid intervention on asymmetric dimethylarginine (ADMA)

W16-P-024 Effect of long-term diet and N-3 fatty acid intervention on asymmetric dimethylarginine (ADMA)

The Long-Term Effects of Diet and Exercise on Body Composition in Overweight Subjects

1001 Obesity is a significant and widespread dilemma in the United States. Individuals that successfully overcome obesity often struggle to maintain weight loss. PURPOSE: To examine the long-term sustainability of changes in body mass, body composition, and blood profile in previously overweight and obese subjects who participated in a low-calorie diet and exercise program. METHODS: Twenty-two subjects participated in a 10-week weight loss intervention program followed by a nine-month weight loss maintenance program. A 1200-calorie diet was used during intervention. Daily physical activity was recorded via pedometers. Throughout maintenance, total caloric intake was increased to 12 times body weight (in pounds) while daily exercise was continued. Body mass and body composition were measured prior to the 10-week intervention (pretest), prior to the maintenance program (midtest), and following the maintenance program (posttest). Blood profiles were measured in 20 of the 22 subjects. Data were analyzed by repeated measures ANOVA with significance set at p < 0.05. RESULTS: Body mass (−6.3 kg), body mass index (−2.3), percent body fat (−3.0%), fat mass (−4.8 kg), hip circumference (−5.1 cm), and sagittal diameter (−3.6 cm) were reduced significantly during the 10-week weight loss intervention. There were also significant reductions in total cholesterol (−32.6 mg/dl), low-density lipoprotein cholesterol (−20.2 mg/dl), and blood glucose (−8.8 mg/dl) as a result of intervention. There were small, yet non-significant, changes in body mass (+2.5 kg), body mass index (+0.7), percent body fat (−1.2%), fat mass (+0.4 kg), and hip circumference (+0.8 cm) during the nine-month maintenance phase. Similarly, total cholesterol (+15.1 mg/dl), LDL-C (+13.2 mg/dl), and glucose (+4.2 mg/dl) did not significantly change during maintenance. Lean body mass did not change during intervention and maintenance. CONCLUSION: Nine-months following intervention, reductions in body mass, body composition, and blood profile measures can be maintained.

The Long-Term Effects of Diet and Exercise on Body Composition in Overweight Subjects

The Long-Term Effects of Diet and Exercise on Body Composition in Overweight Subjects

Long-term effects of diet on leptin, energy intake, and activity in a model of diet-induced obesity.

This study investigated the effect of long-term high-fat sucrose (HFS) or low-fat complex-carbohydrate (LFCC) diet consumption on leptin, insulin, fat cell size, energy intake, and markers of activity to ascertain the role that leptin plays in long-term energy balance in a model of diet-induced obesity. Female Fischer 344 rats were fed either a HFS or LFCC diet ad libitum for a period of 20 mo. Measurements of leptin concentration, insulin concentration, and adipocyte size were performed at 2 wk, 2 mo, 6 mo, and 20 mo. Body weight and energy intake were measured weekly for calculation of feed efficiency. Body temperature and activity levels were assessed over a 5-day period after 12 mo of the dietary intervention. Plasma leptin and insulin concentrations were significantly elevated within 2 wk of HFS diet consumption and remained elevated throughout the course of the study. After 2 mo, the adipocytes of the HFS group were significantly larger and continued to increase in size throughout the course of the study. A significant correlation was noted between leptin and adipocyte cell size (r = 0.96, P < 0.01). However, despite elevated leptin, energy intake was similar, and the HFS group weighed significantly more than the LFCC group, as a result of a higher feed efficiency. There were no significant differences in body temperature or activity levels between the groups. These results demonstrate that a HFS diet causes hyperleptinemia and hyperinsulinemia before adipocyte size is increased and suggests that leptin resistance may be present or, alternatively, that leptin does not to play a major role in the long-term regulation of energy intake or activity levels in this model.

Effects of type of fat in the diet on iron bioavailability assessed in suckling and weanling rats

Differences in iron bioavailability from human milk and milk formulas may in part be due to differences in lipid composition. We investigated the short and long term effects of diets based on different fats [corn, coconut, olive, or soy oil, human milk fat (HMF) and a formula fat blend (FF)] on iron absorption in rats. Suckling rat pups dosed with 59Fe-labeled diets containing different fat sources were killed after 6 h, and blood and individual tissues were counted. Iron availability was estimated by % 59Fe in blood. Pups dosed with a more saturated fat (coconut oil) had a higher % 59Fe in blood than those fed other fat sources. Weanling rats were used to determine iron bioavailability from fat sources using both the hemoglobin repletion method and whole body counting. Hemoglobin regeneration was significantly higher for rats fed the HMF diet (8.4 ± 0.5 g/dl) than from the FF diet (6.5±0.6 g/dl) or the corn oil diet (less saturated) (6.4 ± 0.3 g/dl). Rats fed diets based on coconut oil (more saturated) had significantly higher % 59Fe retention (61.6 ± 1.4) than rats fed diets based on FF (49.8 ± 3.4). There was a significant positive association between oleic acid in the diet and oleic acid in the intestinal mucosa (r = 0.95, p < 0.05) and between linoleic acid in the diet and linoleic acid in the intestinal mucosa (r = 0.97, p < 0.05) suggesting that the dietary treatment altered the fatty acid composition of the brush border membrane. Our results suggest that saturated fats may increase iron absorption and that part of this may be achieved by changes in the fatty acid composition of the intestinal mucosa. Hemoglobin regeneration and % 59Fe retention data suggest that differences in iron absorption from infant diets may in part be due to differences in fat composition. Therefore, lipid composition of infant formulas should also be taken into consideration as a factor influencing iron bioavailability.

Use of combined diet and colestipol in long-term (7--7 1/2 years) treatment of patients with type II hyperlipoproteinemia.

Long-term effects of diet and colestipol (a bile acid sequestrant) were studied in 25 patients with familial type II hyperlipoproteinemia. Serum lipids and body weights of an initial group of 30 patients were stabilized by low cholesterol-saturated fat-refined carbohydrate diet and the patients were then randomized into placebo and drug-treatment groups. After explaining that the drug is nontoxic and effective in lowering serum lipids, total cholesterol (C) and low-density lipoprotein cholesterol (LDL-C), colestipol (30 g/day) and diet were given to the 25 patients who remained in the long-term follow-up program. The treatment resulted in highly significant lowering of serum lipids (mg/dl, mean +/- SEM): C and LDL-C from 412.7 +/- 24.4 and 331.1 +/- 22.8 to 270 +/- 11.0 and 188.1 +/- 13.8, respectively (p less than 0.001 in each instance) over 7--7 1/2 years. Although we observed no absolute increase in high density lipoprotein (HDL), the HDL/LDL ratio was elevated. Long-term colestipol and diet treatment reduced the xanthoma size and stabilized serially angiographically visualized atherosclerotic lesions in 21 of the 25 patients who showed a satisfactory hypolipemic response. It did not cause nutritional or metabolic disturbances.