| Autor: |
Karl JP; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts., Cole RE; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts., Berryman CE; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts.; 2 Oak Ridge Institute of Science and Education , Oak Ridge, Tennessee., Finlayson G; 3 School of Psychology, University of Leeds , Leeds, United Kingdom ., Radcliffe PN; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts.; 2 Oak Ridge Institute of Science and Education , Oak Ridge, Tennessee., Kominsky MT; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts., Murphy NE; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts., Carbone JW; 2 Oak Ridge Institute of Science and Education , Oak Ridge, Tennessee.; 4 School of Health Sciences, Eastern Michigan University , Ypsilanti, Michigan., Rood JC; 5 Pennington Biomedical Research Center , Baton Rouge, Louisiana., Young AJ; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts.; 2 Oak Ridge Institute of Science and Education , Oak Ridge, Tennessee., Pasiakos SM; 1 Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine , Natick, Massachusetts. |
| Abstrakt: |
Karl, J. Philip, Renee E. Cole, Claire E. Berryman, Graham Finlayson, Patrick N. Radcliffe, Matthew T. Kominsky, Nancy E. Murphy, John W. Carbone, Jennifer C. Rood, Andrew J. Young, and Stefan M. Pasiakos. Appetite suppression and altered food preferences coincide with changes in appetite-mediating hormones during energy deficit at high altitude, but are not affected by protein intake. High Alt Med Biol. 19:156-169, 2018.-Anorexia and unintentional body weight loss are common during high altitude (HA) sojourn, but underlying mechanisms are not fully characterized, and the impact of dietary macronutrient composition on appetite regulation at HA is unknown. This study aimed to determine the effects of a hypocaloric higher protein diet on perceived appetite and food preferences during HA sojourn and to examine longitudinal changes in perceived appetite, appetite mediating hormones, and food preferences during acclimatization and weight loss at HA. Following a 21-day level (SL) period, 17 unacclimatized males ascended to and resided at HA (4300 m) for 22 days. At HA, participants were randomized to consume measured standard-protein (1.0 g protein/kg/d) or higher protein (2.0 g/kg/d) hypocaloric diets (45% carbohydrate, 30% energy restriction) and engaged in prescribed physical activity to induce an estimated 40% energy deficit. Appetite, food preferences, and appetite-mediating hormones were measured at SL and at the beginning and end of HA. Diet composition had no effect on any outcome. Relative to SL, appetite was lower during acute HA (days 0 and 1), but not different after acclimatization and weight loss (HA day 18), and food preferences indicated an increased preference for sweet- and low-protein foods during acute HA, but for high-fat foods after acclimatization and weight loss. Insulin, leptin, and cholecystokinin concentrations were elevated during acute HA, but not after acclimatization and weight loss, whereas acylated ghrelin concentrations were suppressed throughout HA. Findings suggest that appetite suppression and altered food preferences coincide with changes in appetite-mediating hormones during energy deficit at HA. Although dietary protein intake did not impact appetite, the possible incongruence with food preferences at HA warrants consideration when developing nutritional strategies for HA sojourn. |
