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Hall KD, Guo J. Obesity Energetics: Body Weight Regulation and the Effects of Diet Composition. Gastroenterology 2017; 152:1718-1727.e3. [PMID: 28193517 PMCID: PMC5568065 DOI: 10.1053/j.gastro.2017.01.052] [Citation(s) in RCA: 196] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 01/19/2017] [Accepted: 01/23/2017] [Indexed: 12/14/2022]
Abstract
Weight changes are accompanied by imbalances between calorie intake and expenditure. This fact is often misinterpreted to suggest that obesity is caused by gluttony and sloth and can be treated by simply advising people to eat less and move more. Rather various components of energy balance are dynamically interrelated and weight loss is resisted by counterbalancing physiological processes. While low-carbohydrate diets have been suggested to partially subvert these processes by increasing energy expenditure and promoting fat loss, our meta-analysis of 32 controlled feeding studies with isocaloric substitution of carbohydrate for fat found that both energy expenditure (26 kcal/d; P <.0001) and fat loss (16 g/d; P <.0001) were greater with lower fat diets. We review the components of energy balance and the mechanisms acting to resist weight loss in the context of static, settling point, and set-point models of body weight regulation, with the set-point model being most commensurate with current data.
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152
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Timeline of changes in appetite during weight loss with a ketogenic diet. Int J Obes (Lond) 2017; 41:1224-1231. [PMID: 28439092 PMCID: PMC5550564 DOI: 10.1038/ijo.2017.96] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 03/22/2017] [Accepted: 04/02/2017] [Indexed: 12/25/2022]
Abstract
Background/objective: Diet-induced weight loss (WL) leads to increased hunger and reduced fullness feelings, increased ghrelin and reduced satiety peptides concentration (glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK) and peptide YY (PYY)). Ketogenic diets seem to minimise or supress some of these responses. The aim of this study was to determine the timeline over which changes in appetite occur during progressive WL with a ketogenic very-low-energy diet (VLED). Subjects/methods: Thirty-one sedentary adults (18 men), with obesity (body mass index: 37±4.5 kg m−2) underwent 8 weeks (wks) of a VLED followed by 4 wks of weight maintenance. Body weight and composition, subjective feelings of appetite and appetite-related hormones (insulin, active ghrelin (AG), active GLP-1, total PYY and CCK) were measured in fasting and postprandially, at baseline, on day 3 of the diet, 5 and 10% WL, and at wks 9 and 13. Data are shown as mean±s.d. Results: A significant increase in fasting hunger was observed by day 3 (2±1% WL), (P<0.01), 5% WL (12±8 days) (P<0.05) and wk 13 (17±2% WL) (P<0.05). Increased desire to eat was observed by day 3 (P<0.01) and 5% WL (P<0.05). Postprandial prospective food consumption was significantly reduced at wk 9 (16±2% WL) (P<0.01). Basal total PYY was significantly reduced at 10% WL (32±8 days) (P<0.05). Postprandial active GLP-1 was increased at 5% WL (P<0.01) and CCK reduced at 5 and 10% WL (P<0.01, for both) and wk 9 (P<0.001). Basal and postprandial AG were significantly increased at wk 13 (P<0.001, both). Conclusions: WL with a ketogenic VLED transiently increases the drive to eat up to 3 weeks (5% WL). After that, and while participants are ketotic, a 10–17% WL is not associated with increased appetite. However, hunger feelings and AG concentrations increase significantly from baseline, once refeeding occurs.
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153
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Noakes TD, Windt J. Evidence that supports the prescription of low-carbohydrate high-fat diets: a narrative review. Br J Sports Med 2017; 51:133-139. [PMID: 28053201 DOI: 10.1136/bjsports-2016-096491] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2016] [Indexed: 12/15/2022]
Abstract
Low-carbohydrate high-fat (LCHF) diets are a highly contentious current topic in nutrition. This narrative review aims to provide clinicians with a broad overview of the effects of LCHF diets on body weight, glycaemic control and cardiovascular risk factors while addressing some common concerns and misconceptions. Blood total cholesterol and LDL-cholesterol concentrations show a variable, highly individual response to LCHF diets, and should be monitored in patients adhering to this diet. In contrast, available evidence from clinical and preclinical studies indicates that LCHF diets consistently improve all other markers of cardiovascular risk-lowering elevated blood glucose, insulin, triglyceride, ApoB and saturated fat (especially palmitoleic acid) concentrations, reducing small dense LDL particle numbers, glycated haemoglobin (HbA1c) levels, blood pressure and body weight while increasing low HDL-cholesterol concentrations and reversing non-alcoholic fatty liver disease (NAFLD). This particular combination of favourable modifications to all these risk factors is a benefit unique to LCHF diets. These effects are likely due in part to reduced hunger and decreased ad libitum calorie intake common to low-carbohydrate diets, allied to a reduction in hyperinsulinaemia, and reversal of NAFLD. Although LCHF diets may not be suitable for everyone, available evidence shows this eating plan to be a safe and efficacious dietary option to be considered. LCHF diets may also be particularly beneficial in patients with atherogenic dyslipidaemia, insulin resistance, and the frequently associated NAFLD.
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Affiliation(s)
- Timothy David Noakes
- Department of Human Biology, University of Cape Town, Sports Science Institute of South Africa, Newlands, Cape Town, South Africa
| | - Johann Windt
- Department of Experimental Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Hip Health and Mobility, University of British Columbia, Vancouver, British Columbia, Canada
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154
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Hall KD. A review of the carbohydrate-insulin model of obesity. Eur J Clin Nutr 2017; 71:323-326. [PMID: 28074888 DOI: 10.1038/ejcn.2016.260] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 10/10/2016] [Indexed: 02/07/2023]
Abstract
The carbohydrate-insulin model of obesity theorizes that diets high in carbohydrate are particularly fattening due to their propensity to elevate insulin secretion. Insulin directs the partitioning of energy toward storage as fat in adipose tissue and away from oxidation by metabolically active tissues and purportedly results in a perceived state of cellular internal starvation. In response, hunger and appetite increases and metabolism is suppressed, thereby promoting the positive energy balance associated with the development of obesity. Several logical consequences of this carbohydrate-insulin model of obesity were recently investigated in a pair of carefully controlled inpatient feeding studies whose results failed to support key model predictions. Therefore, important aspects of carbohydrate-insulin model have been experimentally falsified suggesting that the model is too simplistic. This review describes the current state of the carbohydrate-insulin model and the implications of its recent experimental tests.
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Affiliation(s)
- K D Hall
- National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
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155
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Yamazaki T, Okawa S, Takahashi M. The effects on weight loss and gene expression in adipose and hepatic tissues of very-low carbohydrate and low-fat isoenergetic diets in diet-induced obese mice. Nutr Metab (Lond) 2016; 13:78. [PMID: 27826354 PMCID: PMC5100287 DOI: 10.1186/s12986-016-0139-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 10/24/2016] [Indexed: 12/23/2022] Open
Abstract
Background Obesity is caused by excessive fat or carbohydrate intake. The improvement of obesity is an important issue, especially in Western societies. Both low-carbohydrate diet (LCD) and low-fat diet (LFD) are used to achieve weight loss in humans. To clarify the mechanisms underlying LCD-induced weight loss, especially in early stage, we compared the gene expression in liver, white adipose tissue (WAT) and brown adipose tissue (BAT) of a very-low carbohydrate diet (VLCD)- and LFD-fed diet-induced obese (DIO) mice. Methods DIO male ddY mice were divided into high-fat diet (HFD), and isoenergetic VLCD and LFD groups. Pair-feeding was performed in the VLCD and LFD groups. Three weeks later, the body, liver, WAT and BAT were weighed and the serum and hepatic lipids, the mRNA expression levels in each tissue, and energy metabolism were analyzed. Results The caloric intake of the VLCD-fed mice was initially reduced but was subsequently restored. The total energy intake was similar in the VLCD- and LFD-fed mice. There was a similar decrease in the BW of the VLCD- and LFD-fed mice. The VLCD-fed mice had elevated levels of serum fibroblast growth factor 21 (FGF21) and ketone bodies, which are known to increase energy expenditure. The browning of WAT was observed to a greater extent in the VLCD-fed mice. Moreover, in the VLCD-fed mice, BAT activation was observed, the weight of the BAT was decreased, and the expression of G-protein-coupled receptor 120, type 2 iodothyronine deiodinase, and FGF21 in BAT was extremely increased. Although the energy expenditure of the VLCD- and LFD-fed mice did not differ, that of the VLCD-fed mice was sometimes higher during the dark cycle. Hepatic TG accumulation was reduced in LFD-fed mice due to their decreased fatty acid uptake but not in the VLCD-fed mice. The pro-inflammatory macrophage ratio was increased in the WAT of VLCD-fed mice. Conclusions After 3 weeks, the isoenergetic VLCD- and LFD-fed DIO mice showed similar weight loss. The VLCD-fed mice increased serum concentration of FGF21 and ketone bodies, and marker mRNA levels of browning in WAT, activation in BAT and hepatic lipogenesis.
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Affiliation(s)
- Tomomi Yamazaki
- Department of Nutritional Science, National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8636 Japan
| | - Sumire Okawa
- Department of Nutritional Science, National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8636 Japan
| | - Mayumi Takahashi
- Department of Life Science, Osaka Women's Junior College, 3-8-1 Kasugaoka, Fujiidera City, Osaka 583-8558 Japan
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156
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Lodi A, Karsten B, Bosco G, Gómez-López M, Brandão PP, Bianco A, Paoli A. The Effects of Different High-Protein Low-Carbohydrates Proprietary Foods on Blood Sugar in Healthy Subjects. J Med Food 2016; 19:1085-1095. [PMID: 27754766 DOI: 10.1089/jmf.2016.0072] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The aim of this study was to analyze the effects on blood sugar concentrations through the calculation of the glycemic score (GS) of 10 different high-protein low-carbohydrates (CHOs) proprietary foods that are commonly used as meals during very low-CHO ketogenic diets or during low-CHO diets. Fourteen healthy females were tested for their glycemic response curve elicited by 1000 kJ of glucose three times within a 3-week period (one test each week) compared with one of 10 test foods once on separate days twice a week. After determining the GS of each food in each individual, the mean GS of each test food was calculated. All test foods, compared with glucose, produced a significantly lower glycemic response. The GS of all test food resulted in being lower than 25 and the difference between the mean glycemia after the intake of glucose (mean 122 ± 15 mg/dL) and after the intake of the sweet test foods (mean 89 ± 7 mg/dL) was 33 mg/dL (P < .001), whereas the difference between the mean glycemia after the intake of glucose and after the intake of savory test foods (mean 91 ± 8 mg/dL) was of 31 mg/dL (P < .001). CONCLUSIONS The reformulation of ultraprocessed ready-to-consume foods in a low-CHO, high-protein version can produce a significantly lower glycemic response whilst maintaining the valued ready-to-use format and high palatability demanded by consumers. The low impact on postprandial glycemia and the nutritional characteristics of these proprietary foods makes them useful in both weight control management strategies and in the care management of diabetes.
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Affiliation(s)
- Alessandra Lodi
- 1 Department of Biomedical Sciences, University of Padova , Padova, Italy
| | - Bettina Karsten
- 2 Department of Life and Sports Sciences, University of Greenwich , Medway, United Kingdom
| | - Gerardo Bosco
- 1 Department of Biomedical Sciences, University of Padova , Padova, Italy
| | - Manuel Gómez-López
- 3 Department of Physical Activity and Sport, University of Murcia , Murcia, Spain
| | - Paula Paraguassú Brandão
- 4 Human Kinetics Laboratory of the Federal University of the State of Rio de Janeiro , Rio de Janeiro, Brazil
| | - Antonino Bianco
- 5 Sport and Exercise Sciences Research Unit, University of Palermo , Palermo, Italy
| | - Antonio Paoli
- 1 Department of Biomedical Sciences, University of Padova , Padova, Italy
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157
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Moro T, Tinsley G, Bianco A, Marcolin G, Pacelli QF, Battaglia G, Palma A, Gentil P, Neri M, Paoli A. Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. J Transl Med 2016; 14:290. [PMID: 27737674 PMCID: PMC5064803 DOI: 10.1186/s12967-016-1044-0] [Citation(s) in RCA: 413] [Impact Index Per Article: 51.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 10/03/2016] [Indexed: 01/10/2023] Open
Abstract
Background Intermittent fasting (IF) is an increasingly popular dietary approach used for weight loss and overall health. While there is an increasing body of evidence demonstrating beneficial effects of IF on blood lipids and other health outcomes in the overweight and obese, limited data are available about the effect of IF in athletes. Thus, the present study sought to investigate the effects of a modified IF protocol (i.e. time-restricted feeding) during resistance training in healthy resistance-trained males. Methods Thirty-four resistance-trained males were randomly assigned to time-restricted feeding (TRF) or normal diet group (ND). TRF subjects consumed 100 % of their energy needs in an 8-h period of time each day, with their caloric intake divided into three meals consumed at 1 p.m., 4 p.m., and 8 p.m. The remaining 16 h per 24-h period made up the fasting period. Subjects in the ND group consumed 100 % of their energy needs divided into three meals consumed at 8 a.m., 1 p.m., and 8 p.m. Groups were matched for kilocalories consumed and macronutrient distribution (TRF 2826 ± 412.3 kcal/day, carbohydrates 53.2 ± 1.4 %, fat 24.7 ± 3.1 %, protein 22.1 ± 2.6 %, ND 3007 ± 444.7 kcal/day, carbohydrates 54.7 ± 2.2 %, fat 23.9 ± 3.5 %, protein 21.4 ± 1.8). Subjects were tested before and after 8 weeks of the assigned diet and standardized resistance training program. Fat mass and fat-free mass were assessed by dual-energy x-ray absorptiometry and muscle area of the thigh and arm were measured using an anthropometric system. Total and free testosterone, insulin-like growth factor 1, blood glucose, insulin, adiponectin, leptin, triiodothyronine, thyroid stimulating hormone, interleukin-6, interleukin-1β, tumor necrosis factor α, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured. Bench press and leg press maximal strength, resting energy expenditure, and respiratory ratio were also tested. Results After 8 weeks, the 2 Way ANOVA (Time * Diet interaction) showed a decrease in fat mass in TRF compared to ND (p = 0.0448), while fat-free mass, muscle area of the arm and thigh, and maximal strength were maintained in both groups. Testosterone and insulin-like growth factor 1 decreased significantly in TRF, with no changes in ND (p = 0.0476; p = 0.0397). Adiponectin increased (p = 0.0000) in TRF while total leptin decreased (p = 0.0001), although not when adjusted for fat mass. Triiodothyronine decreased in TRF, but no significant changes were detected in thyroid-stimulating hormone, total cholesterol, high-density lipoprotein, low-density lipoprotein, or triglycerides. Resting energy expenditure was unchanged, but a significant decrease in respiratory ratio was observed in the TRF group. Conclusions Our results suggest that an intermittent fasting program in which all calories are consumed in an 8-h window each day, in conjunction with resistance training, could improve some health-related biomarkers, decrease fat mass, and maintain muscle mass in resistance-trained males.
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Affiliation(s)
- Tatiana Moro
- Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - Grant Tinsley
- Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX, USA
| | - Antonino Bianco
- Sport and Exercise Sciences Research Unit, University of Palermo, Palermo, Italy
| | - Giuseppe Marcolin
- Department of Biomedical Sciences, University of Padova, Padua, Italy
| | | | - Giuseppe Battaglia
- Sport and Exercise Sciences Research Unit, University of Palermo, Palermo, Italy
| | - Antonio Palma
- Sport and Exercise Sciences Research Unit, University of Palermo, Palermo, Italy
| | - Paulo Gentil
- College of Physical Education and Dance, Federal University of Goias, Goiania, Brazil
| | - Marco Neri
- Italian Fitness Federation, Ravenna, Italy
| | - Antonio Paoli
- Department of Biomedical Sciences, University of Padova, Padua, Italy.
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158
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Carneiro L, Geller S, Hébert A, Repond C, Fioramonti X, Leloup C, Pellerin L. Hypothalamic sensing of ketone bodies after prolonged cerebral exposure leads to metabolic control dysregulation. Sci Rep 2016; 6:34909. [PMID: 27708432 PMCID: PMC5052612 DOI: 10.1038/srep34909] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 09/21/2016] [Indexed: 01/08/2023] Open
Abstract
Ketone bodies have been shown to transiently stimulate food intake and modify energy homeostasis regulatory systems following cerebral infusion for a moderate period of time (<6 hours). As ketone bodies are usually enhanced during episodes of fasting, this effect might correspond to a physiological regulation. In contrast, ketone bodies levels remain elevated for prolonged periods during obesity, and thus could play an important role in the development of this pathology. In order to understand this transition, ketone bodies were infused through a catheter inserted in the carotid to directly stimulate the brain for a period of 24 hours. Food ingested and blood circulating parameters involved in metabolic control as well as glucose homeostasis were determined. Results show that ketone bodies infusion for 24 hours increased food intake associated with a stimulation of hypothalamic orexigenic neuropeptides. Moreover, insulinemia was increased and caused a decrease in glucose production despite an increased resistance to insulin. The present study confirms that ketone bodies reaching the brain stimulates food intake. Moreover, we provide evidence that a prolonged hyperketonemia leads to a dysregulation of energy homeostasis control mechanisms. Finally, this study shows that brain exposure to ketone bodies alters insulin signaling and consequently glucose homeostasis.
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Affiliation(s)
- Lionel Carneiro
- Department of Physiology, University of Lausanne, 1005 Lausanne, Switzerland
| | - Sarah Geller
- Department of Physiology, University of Lausanne, 1005 Lausanne, Switzerland
| | - Audrey Hébert
- Department of Physiology, University of Lausanne, 1005 Lausanne, Switzerland
| | - Cendrine Repond
- Department of Physiology, University of Lausanne, 1005 Lausanne, Switzerland
| | - Xavier Fioramonti
- UMR CNRS 6265-INRA 1324-Univ. Bourgogne Franche-Comté Centre des sciences du goût et de l'alimentation, 21000 Dijon, France
| | - Corinne Leloup
- UMR CNRS 6265-INRA 1324-Univ. Bourgogne Franche-Comté Centre des sciences du goût et de l'alimentation, 21000 Dijon, France
| | - Luc Pellerin
- Department of Physiology, University of Lausanne, 1005 Lausanne, Switzerland
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159
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Volicer L. Fear of Dementia. J Am Med Dir Assoc 2016; 17:875-8. [DOI: 10.1016/j.jamda.2016.06.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 06/23/2016] [Accepted: 06/23/2016] [Indexed: 01/27/2023]
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160
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Webster CC, Noakes TD, Chacko SK, Swart J, Kohn TA, Smith JAH. Gluconeogenesis during endurance exercise in cyclists habituated to a long-term low carbohydrate high-fat diet. J Physiol 2016; 594:4389-405. [PMID: 26918583 DOI: 10.1113/jp271934] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 02/23/2016] [Indexed: 12/18/2022] Open
Abstract
KEY POINTS Blood glucose is an important fuel for endurance exercise. It can be derived from ingested carbohydrate, stored liver glycogen and newly synthesized glucose (gluconeogenesis). We hypothesized that athletes habitually following a low carbohydrate high fat (LCHF) diet would have higher rates of gluconeogenesis during exercise compared to those who follow a mixed macronutrient diet. We used stable isotope tracers to study glucose production kinetics during a 2 h ride in cyclists habituated to either a LCHF or mixed macronutrient diet. The LCHF cyclists had lower rates of total glucose production and hepatic glycogenolysis but similar rates of gluconeogenesis compared to those on the mixed diet. The LCHF cyclists did not compensate for reduced dietary carbohydrate availability by increasing glucose synthesis during exercise but rather adapted by altering whole body substrate utilization. ABSTRACT Endogenous glucose production (EGP) occurs via hepatic glycogenolysis (GLY) and gluconeogenesis (GNG) and plays an important role in maintaining euglycaemia. Rates of GLY and GNG increase during exercise in athletes following a mixed macronutrient diet; however, these processes have not been investigated in athletes following a low carbohydrate high fat (LCHF) diet. Therefore, we studied seven well-trained male cyclists that were habituated to either a LCHF (7% carbohydrate, 72% fat, 21% protein) or a mixed diet (51% carbohydrate, 33% fat, 16% protein) for longer than 8 months. After an overnight fast, participants performed a 2 h laboratory ride at 72% of maximal oxygen consumption. Glucose kinetics were measured at rest and during the final 30 min of exercise by infusion of [6,6-(2) H2 ]-glucose and the ingestion of (2) H2 O tracers. Rates of EGP and GLY both at rest and during exercise were significantly lower in the LCHF group than the mixed diet group (Exercise EGP: LCHF, 6.0 ± 0.9 mg kg(-1) min(-1) , Mixed, 7.8 ± 1.1 mg kg(-1) min(-1) , P < 0.01; Exercise GLY: LCHF, 3.2 ± 0.7 mg kg(-1) min(-1) , Mixed, 5.3 ± 0.9 mg kg(-1) min(-1) , P < 0.01). Conversely, no difference was detected in rates of GNG between groups at rest or during exercise (Exercise: LCHF, 2.8 ± 0.4 mg kg(-1) min(-1) , Mixed, 2.5 ± 0.3 mg kg(-1) min(-1) , P = 0.15). We conclude that athletes on a LCHF diet do not compensate for reduced glucose availability via higher rates of glucose synthesis compared to athletes on a mixed diet. Instead, GNG remains relatively stable, whereas glucose oxidation and GLY are influenced by dietary factors.
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Affiliation(s)
- Christopher C Webster
- Division of Exercise Science and Sports Medicine (ESSM), Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Newlands, South Africa
| | - Timothy D Noakes
- Division of Exercise Science and Sports Medicine (ESSM), Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Newlands, South Africa
| | - Shaji K Chacko
- Department of Pediatrics, Children's Nutrition Research Center, US Department of Agriculture/Agricultural Research Service, Baylor College of Medicine, Houston, TX, USA
| | - Jeroen Swart
- Division of Exercise Science and Sports Medicine (ESSM), Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Newlands, South Africa
| | - Tertius A Kohn
- Division of Exercise Science and Sports Medicine (ESSM), Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Newlands, South Africa
| | - James A H Smith
- Division of Exercise Science and Sports Medicine (ESSM), Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Newlands, South Africa
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161
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Abstract
Awareness that the metabolic phenotype of cells within tumours is heterogeneous - and distinct from that of their normal counterparts - is growing. In general, tumour cells metabolize glucose, lactate, pyruvate, hydroxybutyrate, acetate, glutamine, and fatty acids at much higher rates than their nontumour equivalents; however, the metabolic ecology of tumours is complex because they contain multiple metabolic compartments, which are linked by the transfer of these catabolites. This metabolic variability and flexibility enables tumour cells to generate ATP as an energy source, while maintaining the reduction-oxidation (redox) balance and committing resources to biosynthesis - processes that are essential for cell survival, growth, and proliferation. Importantly, experimental evidence indicates that metabolic coupling between cell populations with different, complementary metabolic profiles can induce cancer progression. Thus, targeting the metabolic differences between tumour and normal cells holds promise as a novel anticancer strategy. In this Review, we discuss how cancer cells reprogramme their metabolism and that of other cells within the tumour microenvironment in order to survive and propagate, thus driving disease progression; in particular, we highlight potential metabolic vulnerabilities that might be targeted therapeutically.
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162
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Rojas-Morales P, Tapia E, Pedraza-Chaverri J. β-Hydroxybutyrate: A signaling metabolite in starvation response? Cell Signal 2016; 28:917-23. [PMID: 27083590 DOI: 10.1016/j.cellsig.2016.04.005] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/09/2016] [Indexed: 02/08/2023]
Abstract
Ketone bodies β-hydroxybutyrate (BHB) and acetoacetate are important metabolic substrates for energy production during prolonged fasting. However, BHB also has signaling functions. Through several metabolic pathways or processes, BHB modulates nutrient utilization and energy expenditure. These findings suggest that BHB is not solely a metabolic intermediate, but also acts as a signal to regulate metabolism and maintain energy homeostasis during nutrient deprivation. We briefly summarize the metabolism and emerging physiological functions of ketone bodies and highlight the potential role for BHB as a signaling molecule in starvation response.
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Affiliation(s)
- Pedro Rojas-Morales
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Edilia Tapia
- Laboratorio de Fisiopatología Renal, Departamento de Nefrología, Instituto Nacional de Cardiología - Ignacio Chávez, Mexico City, Mexico
| | - José Pedraza-Chaverri
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City, Mexico.
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163
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Klement RJ, Sweeney RA. Impact of a ketogenic diet intervention during radiotherapy on body composition: I. Initial clinical experience with six prospectively studied patients. BMC Res Notes 2016; 9:143. [PMID: 26946138 PMCID: PMC4779584 DOI: 10.1186/s13104-016-1959-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/25/2016] [Indexed: 12/27/2022] Open
Abstract
Background Based on promising preclinical data, ketogenic diets (KDs) have been proposed as supplementary measures for cancer patients undergoing standard-of-care therapy. However, data is still scarce on the tolerability and effects of KDs on cancer patients undergoing radiotherapy (RT). Here we present six cases of patients who underwent RT and concurrently consumed a self-administered KD in our clinic within a busy community hospital setting. Methods All patients were followed prospectively with measurements of blood parameters, quality of life and body weight and composition using bioelectrical impedance analysis. Results No adverse diet-related side effects occurred. Two patients had no elevated ketone body levels in serum despite self-reporting compliance to the diet. There was consensus that the KD was satiating and weight loss occurred in all patients, although this was only significant in two patients. Our data indicate that weight loss was mainly due to fat mass loss with concurrent preservation of muscle mass. Overall quality of life remained fairly stable, and all subjects reported feeling good on the diet. Tumor regression occurred as expected in five patients with early stage disease; however one subject with metastatic small cell lung cancer experienced slight progression during three cycles of combined chemotherapy + KD and progressed rapidly after ending the KD. Conclusions Our data lend support to the hypothesis that KDs administered as supportive measures during standard therapy are safe and might be helpful in preservation of muscle mass. Further studies with control groups are needed to confirm these findings and address questions regarding any putative anti-tumor effects. Based on the experience with these six cases we implemented further steps to improve issues with KD compliance and initiated a clinical study that is described in a companion paper.
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Affiliation(s)
- Rainer J Klement
- Department of Radiation Oncology, Leopoldina Hospital Schweinfurt, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany.
| | - Reinhart A Sweeney
- Department of Radiation Oncology, Leopoldina Hospital Schweinfurt, Robert-Koch-Straße 10, 97422, Schweinfurt, Germany.
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Branco AF, Ferreira A, Simões RF, Magalhães-Novais S, Zehowski C, Cope E, Silva AM, Pereira D, Sardão VA, Cunha-Oliveira T. Ketogenic diets: from cancer to mitochondrial diseases and beyond. Eur J Clin Invest 2016; 46:285-98. [PMID: 26782788 DOI: 10.1111/eci.12591] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/12/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND The employment of dietary strategies such as ketogenic diets, which force cells to alter their energy source, has shown efficacy in the treatment of several diseases. Ketogenic diets are composed of high fat, moderate protein and low carbohydrates, which favour mitochondrial respiration rather than glycolysis for energy metabolism. DESIGN This review focuses on how oncological, neurological and mitochondrial disorders have been targeted by ketogenic diets, their metabolic effects, and the possible mechanisms of action on mitochondrial energy homeostasis. The beneficial and adverse effects of the ketogenic diets are also highlighted. RESULTS AND CONCLUSIONS Although the full mechanism by which ketogenic diets improve oncological and neurological conditions still remains to be elucidated, their clinical efficacy has attracted many new followers, and ketogenic diets can be a good option as a co-adjuvant therapy, depending on the situation and the extent of the disease.
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Affiliation(s)
- Ana F Branco
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - André Ferreira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Rui F Simões
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | | | - Cheryl Zehowski
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Elisabeth Cope
- Department of Applied Medical Sciences, University of Southern Maine, Portland, ME, USA
| | - Ana Marta Silva
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Daniela Pereira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Vilma A Sardão
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Teresa Cunha-Oliveira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
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165
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Carneiro L, Geller S, Fioramonti X, Hébert A, Repond C, Leloup C, Pellerin L. Evidence for hypothalamic ketone body sensing: impact on food intake and peripheral metabolic responses in mice. Am J Physiol Endocrinol Metab 2016; 310:E103-15. [PMID: 26530151 DOI: 10.1152/ajpendo.00282.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 10/21/2015] [Indexed: 12/21/2022]
Abstract
Monocarboxylates have been implicated in the control of energy homeostasis. Among them, the putative role of ketone bodies produced notably during high-fat diet (HFD) has not been thoroughly explored. In this study, we aimed to determine the impact of a specific rise in cerebral ketone bodies on food intake and energy homeostasis regulation. A carotid infusion of ketone bodies was performed on mice to stimulate sensitive brain areas for 6 or 12 h. At each time point, food intake and different markers of energy homeostasis were analyzed to reveal the consequences of cerebral increase in ketone body level detection. First, an increase in food intake appeared over a 12-h period of brain ketone body perfusion. This stimulated food intake was associated with an increased expression of the hypothalamic neuropeptides NPY and AgRP as well as phosphorylated AMPK and is due to ketone bodies sensed by the brain, as blood ketone body levels did not change at that time. In parallel, gluconeogenesis and insulin sensitivity were transiently altered. Indeed, a dysregulation of glucose production and insulin secretion was observed after 6 h of ketone body perfusion, which reversed to normal at 12 h of perfusion. Altogether, these results suggest that an increase in brain ketone body concentration leads to hyperphagia and a transient perturbation of peripheral metabolic homeostasis.
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Affiliation(s)
- Lionel Carneiro
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Sarah Geller
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Xavier Fioramonti
- Centre National de la Recherche Scientifique, UMR6265, Centre des Sciences du Goût et de l'Alimentation (CSGA), Dijon, France; Institut National de la Recherche Agronomique, UMR1324, CSGA, Dijon, France; and Université de Bourgogne, CSGA, Dijon, France
| | - Audrey Hébert
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Cendrine Repond
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Corinne Leloup
- Centre National de la Recherche Scientifique, UMR6265, Centre des Sciences du Goût et de l'Alimentation (CSGA), Dijon, France; Institut National de la Recherche Agronomique, UMR1324, CSGA, Dijon, France; and Université de Bourgogne, CSGA, Dijon, France
| | - Luc Pellerin
- Department of Physiology, University of Lausanne, Lausanne, Switzerland;
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166
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Genzer Y, Dadon M, Burg C, Chapnik N, Froy O. Ketogenic diet delays the phase of circadian rhythms and does not affect AMP-activated protein kinase (AMPK) in mouse liver. Mol Cell Endocrinol 2015; 417:124-30. [PMID: 26408964 DOI: 10.1016/j.mce.2015.09.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/14/2015] [Accepted: 09/14/2015] [Indexed: 10/23/2022]
Abstract
Ketogenic diet (KD) is used for weight loss or to treat epilepsy. KD leads to liver AMP-activated protein kinase (AMPK) activation, which would be expected to inhibit gluconeogenesis. However, KD leads to increased hepatic glucose output. As AMPK and its active phosphorylated form (pAMPK) show circadian oscillation, this discrepancy could stem from wrong-time-of-day sampling. The effect of KD was tested on mouse clock gene expression, AMPK, mTOR, SIRT1 and locomotor activity for 2 months and compared to low-fat diet (LFD). KD led to 1.5-fold increased levels of blood glucose and insulin. Brain pAMPK/AMPK ratio was 40% higher under KD, whereas that in liver was not affected. KD led to 40% and 20% down-regulation of the ratio of pP70S6K/P70S6K, the downstream target of mTOR, in the brain and liver, respectively. SIRT1 levels were 40% higher in the brain, but 40% lower in the liver of KD-fed mice. Clock genes showed delayed rhythms under KD. In the brain of KD-fed mice, amplitudes of clock genes were down-regulated, whereas 6-fold up-regulation was found in the liver. The metabolic state under KD indicates reduced satiety in the brain and reduced anabolism alongside increased gluconeogenesis in the liver.
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Affiliation(s)
- Yoni Genzer
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Maayan Dadon
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Chen Burg
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Nava Chapnik
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Oren Froy
- Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
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167
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Affiliation(s)
- Peter Clifton
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
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168
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Yum MS, Lee M, Woo DC, Kim DW, Ko TS, Velíšek L. β-Hydroxybutyrate attenuates NMDA-induced spasms in rats with evidence of neuronal stabilization on MR spectroscopy. Epilepsy Res 2015; 117:125-32. [PMID: 26452206 DOI: 10.1016/j.eplepsyres.2015.08.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/15/2015] [Accepted: 08/06/2015] [Indexed: 01/04/2023]
Abstract
BACKGROUND Infantile spasms (IS) is a devastating epileptic encephalopathy. The ketogenic diet (KD) has been successfully used as a treatment for IS. This study was designed to test whether beta-hydroxybutyrate (BHB), a major metabolite of the KD, is effective in an animal model of IS. METHODS Pregnant rats received betamethasone on gestational day 15. The offspring received either single [30min prior to NMDA-triggered spasms on postnatal day (P) 15] or prolonged (three per day from P12 to P15) i.p. BHB. An additional experiment used repeated bouts of spasms on P12, P13, and P15 with randomized prolonged BHB treatment initiated after the first spasms. We determined the latency to onset of spasms and the number of spasms after the NMDA injection on P15. The rats that received randomized BHB treatment were also monitored with open field, sociability, and fear-conditioning tests and underwent in vivo (1)H MR imaging on a 9.4T MR system after NMDA-induced spasms. The acquired (1)H MR spectra were quantified using LC model. RESULTS Single-dose BHB pretreatment had no effect on spasms. In contrast, prolonged pretreatment with BHB significantly delayed the onset and decreased the frequency of spasms. In addition, randomized prolonged BHB treatment resulted in a significant reduction in number of spasms at P15. BHB treatment had no significant effect on motor activities, but significantly decreased the interactions with strangers and increased the contextual memory. On MR spectroscopic analysis of randomized prolonged BHB-treated rats at 24h after the cluster of spasms, the elevation of GABA, glutamine, glutamate, total creatine, macromolecule-plus lipids, and N-acetylaspartate levels after spasms were significantly attenuated by randomized BHB treatment (p<0.05). SIGNIFICANCE Prolonged administration of BHB directly suppresses development of spasms in a rat model of IS with acute stabilization of brain metabolites. Additionally, BHB appears to decrease the interests to other rats and improve memory responses.
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Affiliation(s)
- Mi-Sun Yum
- Department of Pediatrics, Asan Medical Center, College of Medicine Ulsan University, Seoul, South Korea.
| | - Minyoung Lee
- Department of Pediatrics, Asan Medical Center, College of Medicine Ulsan University, Seoul, South Korea.
| | - Dong-Cheol Woo
- Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul, South Korea.
| | - Dong Wook Kim
- Department of Pediatrics, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, South Korea.
| | - Tae-Sung Ko
- Department of Pediatrics, Asan Medical Center, College of Medicine Ulsan University, Seoul, South Korea.
| | - Libor Velíšek
- Departments of Cell Biology & Anatomy, Pediatrics and Neurology, New York Medical College, Valhalla, NY, United States.
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169
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Zilberter T. Appetite, reward, and obesity: the causes and consequences of eating behaviors. Front Psychol 2015; 6:411. [PMID: 25914667 PMCID: PMC4390902 DOI: 10.3389/fpsyg.2015.00411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 03/23/2015] [Indexed: 11/13/2022] Open
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