Frank L Greenway

Louisiana State University, Baton Rouge, Louisiana, United States

Are you Frank L Greenway?

Claim your profile

Publications (215)1167.95 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Foods that enhance satiety can help consumers to resist environmental cues to eat and help adherence to calorie restriction. The objective of this study was to compare the effect of 2 oat-based breakfast cereals on appetite, satiety, and food intake. Forty-eight healthy individuals, 18 years of age or older, were enrolled in a randomized, crossover trial. Subjects consumed isocaloric servings of either oatmeal or an oat-based ready-to-eat breakfast cereal (RTEC) in random order at least a week apart. Visual analogue scales measuring appetite and satiety were completed before breakfast and throughout the morning. Lunch was served 4 hours after breakfast. The physicochemical properties of oat soluble fiber (β-glucan) were determined. Appetite and satiety responses were analyzed by area under the curve. Food intake and β-glucan properties were analyzed using t tests. Oatmeal increased fullness (p = 0.001) and reduced hunger (p = 0.005), desire to eat (p = 0.001), and prospective intake (p = 0.006) more than the RTEC. Energy intake at lunch was lower after eating oatmeal compared to the RTEC (p = 0.012). Oatmeal had higher viscosity (p = 0.03), β-glucan content, molecular weight (p < 0.001), and radius of gyration (p < 0.001) than the RTEC. Oatmeal suppresses appetite, increases satiety, and reduces energy intake compared to the RTEC. The physicochemical properties of β-glucan and sufficient hydration of oats are important factors affecting satiety and subsequent energy intake.
    Journal of the American College of Nutrition 08/2015; DOI:10.1080/07315724.2015.1032442 · 1.68 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Caffeine and ephedrine was an effective combination therapy for weight loss until ephedrine was removed from the market due to safety concerns. This study investigated the combination of caffeine and albuterol as a possibly safer alternative to ephedrine. In a series of experiments using cultured adipocytes, rat models, and humans, the effects of caffeine and albuterol on lipolysis, metabolic rate, food intake, and body composition were evaluated. Both caffeine and albuterol enhanced lipolysis in cultured adipocytes. Acute treatment of humans with caffeine and/or albuterol increased resting metabolic rate. Longer-term studies of rats revealed a trend for increased metabolic rate with albuterol treatment. There was increased lean mass gain concurrent with decreased fat mass gain with caffeine/albuterol treatment that was greater than albuterol treatment alone. In rats, albuterol with caffeine produced significantly greater increases in lean body mass and reductions in fat mass without changes in food intake after 4-8 weeks of treatment. Since caffeine and albuterol are approved for the treatment of asthma in children and adolescents at the doses tested and change body composition without changing food intake, this combination may deserve further exploration for use in treating pediatric obesity. © 2015 The Obesity Society.
    Obesity 08/2015; DOI:10.1002/oby.21163 · 4.39 Impact Factor
  • C J Rebello · C E ONeil · F L Greenway
    [Show abstract] [Hide abstract]
    ABSTRACT: The metabolic controls of eating are embedded in a neural system that permits an interaction with the environment. The result is an integrated adaptive response that coordinates the internal milieu with the prevailing environment. Securing adequate amounts of fat and optimizing its storage and use has an evolutionary basis. By generating neuronal and endocrine feedback signals, behavior and metabolism could then adapt to fluctuations in food availability. However, in modern society, foods that appeal to the palate are neither in shortage nor are they difficult to procure. These foods can activate brain reward circuitry beyond their evolved 'survival advantage' limits. Many foods high in fat invoke an undeniably pleasurable sensation and could excessively stimulate the brain's reward pathways leading to overeating. However, the high appeal and potential for being eaten in excess notwithstanding, fat has the added distinction of inducing powerful signals in the gut that are transduced to the brain and result in the regulation of appetite. Fatty acids are sensed by G-protein coupled receptors on enteroendocrine cells which triggers the release of peptides involved in appetite regulation. Lipid sensing may also occur through the fatty acid translocase, CD-36, on enterocytes. Additionally, fat can activate dopaminergic systems affecting reward, to promote an inhibition over eating. Prolonging the presence of fats in the gastrointestinal lumen permits the activation of signaling mechanisms. Thylakoids, found within the chloroplasts of plants, are flattened disc-like membranous vesicles in which the light-dependent reactions of photosynthesis occur. By interacting with lipids and delaying fat digestion, thylakoid membranes promote the release of peptides involved in appetite regulation and may influence the reward system. This review explores gut lipid sensing and signaling in the context of appetite regulation. The effects of thylakoid membranes on eating behavior are also reviewed.International Journal of Obesity accepted article preview online, 31 July 2015. doi:10.1038/ijo.2015.142.
    International journal of obesity (2005) 07/2015; DOI:10.1038/ijo.2015.142 · 5.39 Impact Factor
  • R L Kolotkin · S Chen · P Klassen · K Gilder · F L Greenway
    [Show abstract] [Hide abstract]
    ABSTRACT: Weight loss is associated with improved quality of life in some, but not all, weight loss trials. We evaluated changes at 56 weeks in quality of life, measured by the Impact of Weight on Quality of Life-Lite (IWQOL-Lite) questionnaire, in a pooled analysis of patient-level data from four randomized controlled Phase 3 studies of naltrexone/bupropion (NB32 or Contrave®). The total number of subjects was 3362 (NB32 = 2043; placebo = 1319; mean body mass index = 36.3 kg m(2) ; mean age = 46). Improvements in IWQOL-Lite Total Score were greater in subjects treated with NB32 (11.9 points [SE 0.3]) vs. placebo (8.2 points [SE 0.3]; P < 0.001), corresponding to weight reductions of 7.0% (SE 0.2) and 2.3% (SE 0.2), respectively. Greater improvements were also observed for NB32 vs. placebo on all five subscale scores of the IWQOL-Lite. Fifty per cent of NB32-treated subjects achieved clinically meaningful improvements in IWQOL-Lite Total Score vs. 32.3% of placebo-treated subjects (odds ratio, 95% confidence interval; 2.09, 1.79-2.44). Subjects losing the most weight (≥15% of baseline weight) experienced the greatest improvement in IWQOL-Lite Total Score (19.3 points [SE 0.7] for NB32 and 18.7 points [SE 1.3] for placebo; P = 0.624). Improved quality of life was associated with weight reduction and was achieved in more subjects treated with NB32 than placebo. © 2015 World Obesity.
    07/2015; DOI:10.1111/cob.12108
  • Source
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Obesity is a chronic disease with serious health consequences, but weight loss is difficult to maintain through lifestyle intervention alone. Liraglutide, a glucagon-like peptide-1 analogue, has been shown to have potential benefit for weight management at a once-daily dose of 3.0 mg, injected subcutaneously. Methods We conducted a 56-week, double-blind trial involving 3731 patients who did not have type 2 diabetes and who had a body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) of at least 30 or a BMI of at least 27 if they had treated or untreated dyslipidemia or hypertension. We randomly assigned patients in a 2:1 ratio to receive once-daily subcutaneous injections of liraglutide at a dose of 3.0 mg (2487 patients) or placebo (1244 patients); both groups received counseling on lifestyle modification. The coprimary end points were the change in body weight and the proportions of patients losing at least 5% and more than 10% of their initial body weight. Results At baseline, the mean (±SD) age of the patients was 45.1±12.0 years, the mean weight was 106.2±21.4 kg, and the mean BMI was 38.3±6.4; a total of 78.5% of the patients were women and 61.2% had prediabetes. At week 56, patients in the liraglutide group had lost a mean of 8.4±7.3 kg of body weight, and those in the placebo group had lost a mean of 2.8±6.5 kg (a difference of −5.6 kg; 95% confidence interval, −6.0 to −5.1; P<0.001, with last-observation-carried-forward imputation). A total of 63.2% of the patients in the liraglutide group as compared with 27.1% in the placebo group lost at least 5% of their body weight (P<0.001), and 33.1% and 10.6%, respectively, lost more than 10% of their body weight (P<0.001). The most frequently reported adverse events with liraglutide were mild or moderate nausea and diarrhea. Serious events occurred in 6.2% of the patients in the liraglutide group and in 5.0% of the patients in the placebo group. Conclusions In this study, 3.0 mg of liraglutide, as an adjunct to diet and exercise, was associated with reduced body weight and improved metabolic control. (Funded by Novo Nordisk; SCALE Obesity and Prediabetes NN8022-1839 ClinicalTrials.gov number, NCT01272219.)
    New England Journal of Medicine 07/2015; 373(1):11. DOI:10.1056/NEJMoa1411892 · 54.42 Impact Factor
  • Sandra Larrivee · Frank L Greenway · William D Johnson
    [Show abstract] [Hide abstract]
    ABSTRACT: Restaurant eating while optimizing nutrition and maintaining a healthy weight is challenging. Even when nutritional information is available, consumers often consider only calories. A quick and easy method to rate both caloric density and nutrition is an unmet need. A food rating system created to address that need is assessed in this study. The food rating system categorizes food items into 3 color-coded categories: most healthy (green), medium healthy (yellow), or least healthy (red) based on calorie density and general nutritional quality from national guidelines. Nutritional information was downloaded from 20 popular fast-food chains. Nutritional assessments and the 3 color coded categories were compared using the Wilcoxon and Median tests to demonstrate the significance of nutrition differences. Green foods were significantly lower than yellow foods, which in turn were significantly lower than red foods, for calories and calories from fat, in addition to content of total fat, saturated fat and carbohydrates per 100 g serving weight (all P < .02). The green foods had significantly lower cholesterol than the yellow (P = .0006) and red (P < .0001) foods. Yellow foods had less sugar than red foods (P < .0001). Yellow foods were significantly higher in dietary fiber than red foods (P = .001). The food rating color-coded system identifies food items with superior nutrition, and lower caloric density. The smartphone app, incorporating the system, has the potential to improve nutrition; reduce the risk of developing diabetes, hypertension, heart disease, and stroke; and improve public health. © 2015 Diabetes Technology Society.
    Journal of diabetes science and technology 06/2015; DOI:10.1177/1932296815592408
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In addition to their fermentable dietary fiber and the soluble β-glucan fiber, oats have unique avenanthramides that have anti-inflammatory and antioxidant properties that reduce coronary heart disease in human clinical trials. We hypothesized that oat consumption will increase insulin sensitivity, reduce body fat, and improve health span in Caenorhabditis elegans through a mechanism involving the daf-2 gene, which codes for the insulin/insulin-like growth factor-1-like receptor, and that hyperglycemia will attenuate these changes. Caenorhabditis elegans wild type (N2) and the null strains sir-2.1, daf-16, and daf-16/daf-2 were fed Escherichia coli (OP50) and oat flakes (0.5%, 1.0%, or 3%) with and without 2% glucose. Oat feeding decreased intestinal fat deposition in N2, daf-16, or daf-16/daf-2 strains (P < .05); and glucose did not affect intestinal fat deposition response. The N2, daf-16, or sir-2.1 mutant increased the pharyngeal pumping rate (P < .05), a surrogate marker of life span, following oat consumption. Oat consumption increased ckr-1, gcy-8, cpt-1, and cpt-2 mRNA expression in both the N2 and the sir-2.1 mutant, with significantly higher expression in sir-2.1 than in N2 (P < .01). Additional glucose further increased expression 1.5-fold of the 4 genes in N2 (P < .01), decreased the expression of all except cpt-1 in the daf-16 mutant, and reduced mRNA expression of the 4 genes in the daf-16/daf-2 mutant (P < .01). These data suggest that oat consumption reduced fat storage and increased ckr-1, gcy-8, cpt-1, or cpt-2 through the sir-2.1 genetic pathway. Oat consumption may be a beneficial dietary intervention for reducing fat accumulation, augmenting health span, and improving hyperglycemia-impaired lipid metabolism. Copyright © 2015. Published by Elsevier Inc.
    Nutrition research 06/2015; 81. DOI:10.1016/j.nutres.2015.06.007 · 2.59 Impact Factor
  • 06/2015; DOI:10.12688/f1000research.6451.1
  • [Show abstract] [Hide abstract]
    ABSTRACT: By retarding fat digestion, thylakoids, the internal photosynthetic membrane system of green plants, promote the release of satiety hormones. This study examined the effect of consuming a single dose of concentrated extract of thylakoids from spinach on satiety, food intake, lipids, and glucose compared to a placebo. Sixty overweight and obese individuals enrolled in a double-blind randomized crossover study consumed the spinach extract or placebo in random order at least a week apart. Blood was drawn for assessments of lipids and glucose before a standard breakfast meal, followed 4 hours later by a 5 g dose of the extract and a standard lunch. Visual analog scales were administered before lunch and at intervals until an ad libitum pizza dinner served 4 hours later. Two hours after lunch a second blood draw was conducted. Mixed models were used to analyze response changes. Compared to placebo, consuming the spinach extract reduced hunger (p < 0.01) and longing for food over 2 hours (p < 0.01) and increased postprandial plasma glucose concentrations (p < 0.01). There were no differences in plasma lipids and energy intake at dinner, but males showed a trend toward decreased energy intake (p = 0.08). At this dose, the spinach extract containing thylakoids increases satiety over a 2-hour period compared to a placebo. Thylakoid consumption may influence gender-specific food cravings.
    Journal of the American College of Nutrition 06/2015; DOI:10.1080/07315724.2014.1003999 · 1.68 Impact Factor
  • Source
    American Heart Journal 05/2015; 169(5):631-638.e7(May):631-638.e7. DOI:10.1016/j.ahj.2015.02.002. · 4.56 Impact Factor
  • F L Greenway
    [Show abstract] [Hide abstract]
    ABSTRACT: Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (e.g., improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homeostatic, environmental and behavioural factors. In homeostatic regulation, the hypothalamus plays a central role in integrating signals regarding food intake, energy balance and body weight while an 'obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their efforts to achieve and maintain weight loss.International Journal of Obesity accepted article preview online, 21 April 2015. doi:10.1038/ijo.2015.59.
    International journal of obesity (2005) 04/2015; DOI:10.1038/ijo.2015.59 · 5.39 Impact Factor
  • Canadian Journal of Diabetes 04/2015; 39:S48. DOI:10.1016/j.jcjd.2015.01.182 · 0.46 Impact Factor
  • Canadian Journal of Diabetes 04/2015; 39:S36. DOI:10.1016/j.jcjd.2015.01.142 · 0.46 Impact Factor
  • Canadian Journal of Diabetes 04/2015; 39:S48-S49. DOI:10.1016/j.jcjd.2015.01.183 · 0.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Obesity Surgery 03/2015; 25(6). DOI:10.1007/s11695-015-1602-1 · 3.74 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Adverse effects of metformin are primarily related to gastrointestinal (GI) intolerance that could limit titration to an efficacious dose or cause discontinuation of the medication. Because some metformin side effects may be attributable to shifts in the GI microbiome, we tested whether a GI microbiome modulator (GIMM) used in combination with metformin would ameliorate the GI symptoms. A 2-period crossover study design was used with 2 treatment sequences, either placebo in period 1 followed by GIMM in period 2 or vice versa. Study periods lasted for 2 weeks, with a 2-week washout period between. During the first week, type 2 diabetes patients (T2D) who experienced metformin GI intolerance took 500 mg metformin along with their assigned NM504 (GIMM) or placebo treatment with breakfast and with dinner. In the second week, the 10 subjects took 500 mg metformin (t.i.d.), with GIMM or placebo consumed with the first and third daily metformin doses. Subjects were permitted to discontinue metformin dosing if it became intolerable. The combination of metformin and GIMM treatment produced a significantly better tolerance score to metformin than the placebo combination (6.78 ± 0.65 [mean ± SEM] versus 4.45 ± 0.69, P = .0006). Mean fasting glucose levels were significantly (P < .02) lower with the metformin-GIMM combination (121.3 ± 7.8 mg/dl) than with metformin-placebo (151.9 ± 7.8 mg/dl). Combining a GI microbiome modulator with metformin might allow the greater use of metformin in T2D patients and improve treatment of the disease. © 2015 Diabetes Technology Society.
    Journal of diabetes science and technology 03/2015; 9(4). DOI:10.1177/1932296815577425
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: GSK1614235 and KGA-2727 are potent, selective inhibitors of the SGLT1 sodium-dependent glucose transporter. Nonclinical (KGA-2727) and clinical (GSK1614235) trials assessed translation of SGLT1 inhibitor effects from rats to normal human physiology. In rats, KGA-2727 (0.1 mg/kg) or vehicle were given before oral administration of 3-O-methylglucose (3-OMG) containing [(3)H]3-OMG tracer. Tracer absorption and distribution were assessed from plasma, urine and fecal samples. SGLT1 inhibition reduced urine 3-OMG recovery and increased fecal excretion. SGLT1 inhibitor effects on plasma glucose, insulin, GIP, and GLP-1 concentrations were also measured during a standard meal. Incremental glucose, insulin and GIP concentrations were decreased, indicating down-regulation of β-cell and K-cell secretion. Minimal effects were observed in the secretion of the L-cell product, GLP-1. Using a 3-way, cross-over design, twelve healthy human subjects received placebo or GSK1614235 20 mg immediately before or after a meal. Five minutes into the meal, 3-OMG was ingested. Post-meal dosing had little impact, yet pre-meal dosing delayed and reduced 3-OMG absorption, with an AUC(0-10) of 231±31 µg.h/mL vs. 446±31 µg.h/mL, for placebo. Recovery of tracer in urine was 1.2±0.7 g for pre-meal dosing and 2.2±0.1 g for placebo. Incremental concentrations of insulin, C-peptide and GIP, were reduced for 2 hours with pre-meal GSK1614235. Total GLP-1 concentrations were significantly increased and a trend for increased PYY was noted. SGLT1 inhibitors block intestinal glucose absorption and reduce GIP secretion in rats and humans, suggesting SGLT1 glucose transport is critical for GIP release. Conversely, GLP-1 and PYY secretion are enhanced by SGLT1 inhibition in humans. Copyright © 2014, American Journal of Physiology- Gastrointestinal and Liver Physiology.
    AJP Gastrointestinal and Liver Physiology 03/2015; 308(11):ajpgi.00286.2014. DOI:10.1152/ajpgi.00286.2014 · 3.74 Impact Factor
  • Experimental and Clinical Endocrinology & Diabetes 03/2015; 122(03). DOI:10.1055/s-0035-1549086 · 1.76 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective: To evaluate the effects of an egg breakfast on lunchtime energy intake in children (age 4-6 years) and adolescents (age 14-17 years). Methods: In 2 randomized crossover trials, participants received either an egg breakfast or an isocaloric bagel breakfast. In both trials, subsequent lunchtime energy intake was the primary outcome. The trial with adolescents also measured each participant's serum ghrelin, serum peptide YY (PYY), and self-assessment of appetite rated using a visual analog scale. Results: Lunchtime food intakes after egg and bagel breakfasts were not significantly different for either age group. Visual analog scale ratings of hunger and satiety were also not different between the 2 treatments in adolescents. Consumption of the egg breakfast led to a significant increase in serum PYY levels (p = 0.0001) in adolescents. However, increased levels of PYY were not correlated with reduced food intake. Conclusion: Short-term food intake in children and adolescents is not differentially altered by an egg breakfast compared to a bagel breakfast.
    Journal of the American College of Nutrition 03/2015; 34(3):1-6. DOI:10.1080/07315724.2014.942471 · 1.68 Impact Factor

Publication Stats

6k Citations
1,167.95 Total Impact Points

Institutions

  • 2000–2015
    • Louisiana State University
      • • School of Kinesiology
      • • Pennington Biomedical Research Center
      Baton Rouge, Louisiana, United States
  • 1995–2015
    • Pennington Biomedical Research Center
      • Nutrient Sensing and Adipocyte Signaling Laboratory
      Baton Rouge, Louisiana, United States
  • 2011
    • Harvard University
      Cambridge, Massachusetts, United States
  • 2010
    • University of Illinois at Chicago
      Chicago, Illinois, United States
  • 2008
    • Louisiana State University Health Sciences Center New Orleans
      • Department of Ophthalmology
      New Orleans, LA, United States
  • 1977
    • Harbor-UCLA Medical Center
      Torrance, California, United States