Browsing by Author "Reyes, Marcela"

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    Association of fasting orexin-A levels with energy intake at breakfast and subsequent snack in Chilean adolescents
    (2022) Lanuza, Fabian; Reyes, Marcela; Blanco, Estela; Burrows, Raquel; Peirano, Patricio; Algarin, Cecilia; Merono, Tomas; Gahagan, Sheila
    Orexin-A, a hormone secreted by orexin neurons, is involved in caloric-intake regulation. Current understanding is based primarily on animal studies. Studies of orexin in humans are scarce, and to our knowledge there are no prior studies in adolescents. We studied fasting Orexin-A levels related to energy intake at breakfast and a subsequent snack in adolescents (n = 668) from a longitudinal study in Chile. Body-Mass Index (BMI), components of the metabolic syndrome and fasting blood levels of leptin, insulin, ghrelin, and orexin-A were measured. Energy intake was calculated based on food weights before and after the standardized breakfast and subsequent snack. High energy intake was defined as = 75th percentile. We assessed the relationship between orexin-A and high energy intake, adjusting for confounders. Higher orexin levels were associated with high breakfast energy intake (OR: 1.21; 95%CI: 0.98-1.49). Conversely, those with higher orexin levels showed a nonsignificant trend for lower odds of high energy intake for the snack (OR: 0.87; 95%CI: 0.70-1.07). There was a significant interaction between high breakfast energy intake and orexin levels. Those who ate more calories at breakfast displayed a lower inhibitory effect of orexin on eating at the snack (p < 0.05). There was no significant interaction between weight status and orexin. In conclusion, orexin-A levels were associated with breakfast energy intake and inversely related with subsequent snack energy intake in participants whose caloric intake at breakfast was within the normal range. Based on these findings, it appears that the association of orexin-A with energy intake depends on eating behavior.
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    Association of fasting Orexin-A levels with energy intake at breakfast and subsequent snack in Chilean adolescents
    (2022) Rilling, Fabian Lanuza; Reyes, Marcela; Blanco, Estela; Burrows, Raquel; Peirano, Patricio; Algarin, Cecilia; Merono, Tomas; Gahagan, Sheila
    Orexin-A, a hormone secreted by orexin neurons, is involved in caloric-intake regulation. Current understanding is based primarily on animal studies. Studies of orexin in humans are scarce, and to our knowledge there are no prior studies in adolescents. We studied fasting Orexin-A levels related to energy intake at breakfast and a subsequent snack in adolescents (n = 668) from a longitudinal study in Chile. Body-Mass Index (BMI), components of the metabolic syndrome and fasting blood levels of leptin, insulin, ghrelin, and orexin-A were measured. Energy intake was calculated based on food weights before and after the standardized breakfast and subsequent snack. High energy intake was defined as = 75th percentile. We assessed the relationship between orexin-A and high energy intake, adjusting for confounders. Higher orexin levels were associated with high breakfast energy intake (OR: 1.21; 95%CI: 0.98-1.49). Conversely, those with higher orexin levels showed a non-significant trend for lower odds of high energy intake for the snack (OR: 0.87; 95%CI: 0.70-1.07). There was a significant interaction between high breakfast energy intake and orexin levels. Those who ate more calories at breakfast displayed a lower inhibitory effect of orexin on eating at the snack (p < 0.05). There was no significant interaction between weight status and orexin. In conclusion, orexin-A levels were associated with breakfast energy intake and inversely related with subsequent snack energy intake in participants whose caloric intake at breakfast was within the normal range. Based on these findings, it appears that the association of orexin-A with energy intake depends on eating behavior.
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    Beverage industry TV advertising shifts after a stepwise mandatory food marketing restriction: achievements and challenges with regulating the food marketing environment
    (2023) Stoltze, Fernanda Mediano; Correa, Teresa; Aguilar, Camila Luz Corvalan; Taillie, Lindsey Smith; Reyes, Marcela; Carpentier, Francesca Renee Dillman
    Objective: Sugar-sweetened beverages (SSB) are heavily advertised globally, and SSB consumption is linked to increased health risk. To reduce unhealthy food marketing, Chile implemented a regulation for products classified as high in energies, sugar, saturated fat or sodium, starting with a 2016 ban on child-targeted advertising of these products and adding a 06.00-22.00 daytime advertising ban in 2019. This study assesses changes in television advertising prevalence of ready-to-drink beverages, including and beyond SSB, to analyse how the beverage industry shifted its marketing strategies across Chile's implementation phases.Design: Beverage advertisements were recorded during two randomly constructed weeks in April-May of 2016 (pre-implementation) through 2019 (daytime ban). Ad products were classified as 'high-in' or 'non-high-in' according to regulation nutrient thresholds. Ads were analysed for their programme placement and marketing content.Setting
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    Effectiveness of an Intervention of Dietary Counseling for Overweight and Obese Pregnant Women in the Consumption of Sugars and Energy
    (2019) Anleu, Elisa; Reyes, Marcela; Araya, Marcela; Flores, Marcela; Uauy, Ricardo; Garmendia, María Luisa
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    Fasting levels of appetite regulating hormones predict caloric intake at breakfast in a group of Chilean adolescents
    (2022) Lanuza, Fabian; Reyes, Marcela; Blanco, Estela; Burrows, Raquel; Peirano, Patricio; Algarin, Cecilia; Gahagan, Sheila
    Background: Appetite regulation is integral to food intake and is modulated by complex interactions between internal and external stimuli. Hormonal mechanisms which stimulate or inhibit intake have been characterized, but the physiologic effects of serum levels of such hormones in short-term appetite regulation have received little attention. Aim: To evaluate whether fasting levels of orexigenic/anorexigenic hormones were associated with energy intake at breakfast, served soon after drawing a fasting blood sample, in a group of adolescents. Material and Methods: Anthropometry, body composition and fasting blood levels of leptin, insulin, ghrelin, and orexin-A were measured in 655 Chilean adolescents aged 16.8 +/- 0.3 years (52% males). Energy intake was measured at a semi-standardized breakfast. Associations between hormone levels and energy intake were studied using multivariate linear models. Results: Thirty nine percent of participants were overweight/ obese. After an overnight fast, median values for leptin, insulin, ghrelin and orexin-A were 7.3 ng/mL, 6.7 IU/dL, 200.8 pg/mL, and 16.1 pg/mL, respectively. Participants ate on average 637 +/- 239 calories at breakfast. In multivariable models, insulin levels were inversely and independently associated with caloric intake at breakfast (beta = -18.65; p < 0.05), whereas leptin, ghrelin and orexin-A levels were positively and independently associated with intake: beta= 5.56, beta = 0.34 and beta = 8.40, respectively, p < 0.05. Conclusions: Fasting leptin, ghrelin and orexin-A were positively associated with energy intake during breakfast provided soon after the blood draw. Insulin was negatively associated with energy intake. Modifiable factors influencing levels of appetite regulating hormones could be a potential target for influencing food intake.
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    Structural responses to the obesity and non-communicable diseases epidemic : the chilean law of food labeling and advertising
    (2013) Uauy, Ricardo; Corvalán, Camila; Reyes, Marcela; Garmendia, María Luisa