ABSTRACT
In Korea and other Asian countries, traditional high-carbohydrate diets are increasingly associated with metabolic syndrome (MetS) and its complications. As dietary patterns shift, there is a growing need to assess the effect of these changes on health outcomes related to MetS. This study aimed to investigate the prospective relationship between carbohydrate consumption and the risk of MetS and its components. We analyzed data from 7902 participants from the Korean Association Resource, part of the Korean Genome and Epidemiology Study Dietary intakes, including carbohydrates and fiber, were assessed using a validated semi-quantitative food frequency questionnaire, allowing for the calculation of the proportion of total energy from carbohydrates (P_CARB) and the carbohydrate-to-fiber ratio to assess carbohydrate quality. Blood samples were collected after at least eight hours of fasting for laboratory analysis. We employed Cox proportional hazards models to estimate hazard ratios and 95% confidence intervals, focusing on the relationship between the P_CARB and the risk of developing MetS and its individual components, while adjusting for carbohydrate quality. In the fully adjusted model, which accounted for carbohydrate quality as a covariate, individuals in the highest percentile of the P_CARB showed a significantly increased risk of MetS, hypertriglyceridemia, hypo-high density lipoprotein cholesterolemia, dyslipidemia, and high blood pressure, compared to those in the lowest P_CARB group. Spline curve analyses indicated that the risks for MetS and its components consistently escalated with increasing P_CARB, with all p-values for nonlinearity exceeding 0.05. The findings suggest that higher levels of P_CARB are associated with an increased risk of MetS and related conditions, except for high fasting glucose. These results highlight the importance of dietary awareness and potential adjustments for populations consuming high-carbohydrate diets.
Subject(s)
Dietary Carbohydrates , Metabolic Syndrome , Humans , Metabolic Syndrome/epidemiology , Metabolic Syndrome/etiology , Metabolic Syndrome/blood , Male , Female , Republic of Korea/epidemiology , Prospective Studies , Middle Aged , Dietary Carbohydrates/adverse effects , Dietary Carbohydrates/administration & dosage , Adult , Risk Factors , Proportional Hazards Models , Dietary Fiber/administration & dosageABSTRACT
Over the past decades, China has been undergoing rapid economic growth, which may have significantly influenced the dietary patterns and health status of the Chinese population. Our study aimed to assess the associations of potential macronutrient trajectory patterns with chronic diseases and all-cause mortality using the latent class trajectory model (LCTM) and the longitudinal data of the China Health and Nutrition Survey obtained between 1991 and 2015. A 24-hour diet recall was used to assess the dietary intake. The Poisson regression model was employed to investigate the correlations between trajectory patterns and chronic diseases and all-cause mortality. A total of 8115 participants were included in the final analysis. We explored four and three trajectory patterns for male and female populations, respectively. We found that a decreasing very high-carbohydrate trajectory together with a U-shape protein trajectory was associated with a higher risk of diabetes in the male population (odds ratio (OR): 2.23; 95% confidence interval (CI): 1.31-3.77). A similar pattern for moderate protein intake was also associated with the risk of diabetes in the female population (OR: 1.82; 95% CI: 1.18-2.79). In addition, we show that a decreasing low-carbohydrate trajectory and an increasing high-fat trajectory were associated with a lower risk of all-cause mortality (OR: 0.76; 95% CI: 0.60-0.96) and a higher risk of obesity (OR: 1.24; 95% CI: 1.05-1.47) in males. Our results shed light on some salient nutritional problems in China, particularly the dual challenges of undernutrition and overnutrition.
Subject(s)
Diabetes Mellitus , Nutrients , Obesity , Humans , Male , Female , Longitudinal Studies , Obesity/mortality , Obesity/epidemiology , Middle Aged , China/epidemiology , Adult , Diabetes Mellitus/mortality , Diabetes Mellitus/epidemiology , Nutrition Surveys , Diet/statistics & numerical data , Dietary Carbohydrates/administration & dosage , Risk Factors , Aged , Dietary Proteins/administration & dosage , Feeding BehaviorABSTRACT
The ketogenic diet is used worldwide to treat various diseases, especially drug-resistant epilepsies. Medium-chain triglycerides or medium-chain fatty acids, primarily the major ketogenic compound caprylic acid (C8; C8:0), can significantly support ketogenesis. This review examines the effects of concurrent carbohydrate intake on C8-induced ketogenesis. A systematic literature search (PubMed and Web of Science) with subsequent data extraction was performed according to PRISMA guidelines and the Cochrane Handbook. Studies investigating the metabolic response to C8-containing MCT interventions with carbohydrate intake were included. The studies did not include a ketogenic diet. Three intervention groups were created. The quality of the studies was assessed using the RoB II tool, and the meta-analysis was performed using the Cochrane RevMan software. A total of 7 trials, including 4 RCTs, met the inclusion criteria. Ketone production was lower when C8 was combined with carbohydrates compared to MCT intake alone. The lower C8 dose group (11 g) did not show a significantly lower ketogenic effect than the higher dose group (19 g). Forest plot analysis showed heterogeneous data. The data suggest a non-linear relationship between C8, carbohydrate intake and ketone production. Further studies are needed to investigate the influence of different carbohydrates on C8-induced ketogenesis. Limitations include heterogeneous intervention conditions, such as different types of dispersions, caffeine intake, limited number of studies and variability in study design.
Subject(s)
Caprylates , Diet, Ketogenic , Dietary Carbohydrates , Humans , Caprylates/administration & dosage , Diet, Ketogenic/methods , Dietary Carbohydrates/administration & dosage , Ketones/administration & dosageABSTRACT
Artificial intelligence chatbots based on large language models have recently emerged as an alternative to traditional online searches and are also entering the nutrition space. In this study, we wanted to investigate whether the artificial intelligence chatbots ChatGPT and Bard (now Gemini) can create meal plans that meet the dietary reference intake (DRI) for different dietary patterns. We further hypothesized that nutritional adequacy could be improved by modifying the prompts used. Meal plans were generated by 3 accounts for different dietary patterns (omnivorous, vegetarian, and vegan) using 2 distinct prompts resulting in 108 meal plans total. The nutrient content of the plans was subsequently analyzed and compared to the DRIs. On average, the meal plans contained less energy and carbohydrates but mostly exceeded the DRI for protein. Vitamin D and fluoride fell below the DRI for all plans, whereas only the vegan plans contained insufficient vitamin B12. ChatGPT suggested using vitamin B12 supplements in 5 of 18 instances, whereas Bard never recommended supplements. There were no significant differences between the prompts or the tools. Although the meal plans generated by ChatGPT and Bard met most DRIs, there were some exceptions, particularly for vegan diets. These tools maybe useful for individuals looking for general dietary inspiration, but they should not be relied on to create nutritionally adequate meal plans, especially for individuals with restrictive dietary needs.
Subject(s)
Artificial Intelligence , Diet , Energy Intake , Meals , Humans , Recommended Dietary Allowances , Nutrients , Feeding Behavior , Dietary Carbohydrates/administration & dosage , Dietary Supplements , Nutritive Value , Dietary PatternsABSTRACT
Diets for weight loss have a long history but an ideal one has not yet been clearly identified. To compare low-fat and lower carbohydrate diets, we designed The Preventing Overweight by Novel Dietary Strategies (POUNDS) Lost study. This is a 2 × 2 factorial study with diets of 20% or 40% fat and 15% or 25% protein with a graded carbohydrate intake of 35, 45, 55 and 65%. Weight loss, overall, was modest at nearly 6% with all four diets, and no significant dietary difference. The variability in weight loss in each diet group was significant, ranging from greater than 20% to a small weight gain. Studies of genetic variations in relation to weight loss showed that the diet that was selected could significantly affect weight loss, emphasizing that there is no ideal diet and more than one diet can be used to treat obesity. Weight loss was also influenced by the level of baseline triiodothyronine or thyroxine, and baseline carbohydrate and insulin resistance. Achieving a stable Health Eating Food Diversity Index, eating more protein, eating more fiber, engaging in more physical activity, sleeping better and eating less ultra-processed foods were beneficial strategies for weight loss in this trial. Although there is no "ideal diet", both the DASH diet and the Mediterranean diet have clinical trials showing their significant benefit for cardiovascular risk factors. Finally, the lesson of the "Last Chance Diet", which recommended a diet with protein from gelatin, proved that some diets could be hazardous.
Subject(s)
Diet, Carbohydrate-Restricted , Obesity , Weight Loss , Humans , Diet, Carbohydrate-Restricted/methods , Obesity/diet therapy , Diet, Fat-Restricted/methods , Female , Male , Middle Aged , Overweight/diet therapy , Diet, Mediterranean , Adult , Dietary Carbohydrates/administration & dosage , Dietary Proteins/administration & dosage , Insulin ResistanceABSTRACT
The effects and underlying mechanisms of metformin which can improve glucose homeostasis of fish have rarely been explored. This experiment aimed to explore the influence of metformin on growth performance, body composition, liver health, hepatic glucolipid metabolic capacity and IR/PI3K/AKT pathway in grass carp (Ctenopharyngodon idella) fed high-carbohydrate diets. A normal diet (Control) and high carbohydrate diets with metformin supplementation (0.00 %, 0.20 %, 0.40 %, 0.60 % and 0.80 %) were configured. Six groups of healthy fish were fed with the experimental diet for eight weeks. The results showed that the growth performance of grass carp was impaired in high carbohydrate diet. Impairment of IR/PI3K/AKT signalling pathway reduced insulin sensitivity, while hepatic oxidative stress damage and decreased immunity affected liver metabolic function. The glycolysis and lipolysis decrease while the gluconeogenesis and fat synthesis increase, which triggers hyperglycaemia and lipid deposition in the body. Metformin supplementation restored the growth performance of grass carp. Metformin improved IR/PI3K/AKT pathway signalling and alleviated insulin resistance, while liver antioxidant capacity and immunity were enhanced resulting in the restoration of liver health. The elevation of glycolysis and lipolysis maintains glycaemic homeostasis and reduces lipid deposition, respectively. These results suggest that metformin supplementation restores liver health and activates the IR/PI3K/AKT signalling pathway, ameliorating insulin resistance and glucose-lipid metabolism disorders caused by a high-carbohydrate diet. As judged by HOMA-IR, the optimum supplementation level of metformin in grass carp (C. idella) fed a high-carbohydrate diet is 0.67 %.
Subject(s)
Carps , Insulin Resistance , Lipid Metabolism , Liver , Metformin , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , Animals , Carps/metabolism , Carps/growth & development , Metformin/pharmacology , Liver/metabolism , Liver/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction/drug effects , Lipid Metabolism/drug effects , Animal Feed/analysis , Hypoglycemic Agents/pharmacology , Dietary Carbohydrates/administration & dosage , Dietary Carbohydrates/adverse effectsABSTRACT
The aim of this study was to evaluate the potential interplay between a carbohydrate diet and inflammation in atherosclerotic cardiovascular disease (ASCVD) development. ATTICA is a prospective observational study of 3042 adults free of cardiovascular disease (CVD) who were recruited in 2002 and followed for 20 years. Baseline data on carbohydrate intake and inflammatory biomarker levels were collected. Participants were stratified by carbohydrate intake (low vs. high: > 190 g/day) and carbohydrate quality. At the 20-year follow-up in 2022, 1988 participants had complete data for CVD assessment. The overall quantity and quality of carbohydrate intake did not show a significant association with CVD incidence; inflammatory markers were positively correlated with an increased risk of CVD (p-values < 0.05). Chronic systemic inflammation seems to affect the CVD risk of participants who had a higher carbohydrate intake more substantially, as compared to those with low intake. Additionally, individuals with higher high carbohydrate/low fiber intake experienced a higher risk of inflammation-related CVD, compared to those with high carbohydrate/high fiber intake. The presented findings revealed that the effect of inflammation markers on the CVD risk is influenced both by the amount and quality of carbohydrate intake, irrespective of overall dietary habits and clinical and lifestyle characteristics.
Subject(s)
Biomarkers , Cardiovascular Diseases , Dietary Carbohydrates , Inflammation , Humans , Male , Female , Inflammation/blood , Middle Aged , Cardiovascular Diseases/etiology , Cardiovascular Diseases/epidemiology , Dietary Carbohydrates/administration & dosage , Dietary Carbohydrates/adverse effects , Prospective Studies , Adult , Biomarkers/blood , Heart Disease Risk Factors , Risk Factors , Aged , Feeding Behavior , Incidence , Diet/adverse effectsABSTRACT
BACKGROUND: The differential effects of pecans versus other popular snack foods on appetite and blood markers of metabolism and satiety have not been well studied. This study investigated the effects of a single mid-morning snack of pecans or tortilla chips on subjective appetite, food intake, blood measures of hormones and metabolites, and resting energy expenditure. METHODS: Twenty participants with overweight and obesity were enrolled in a within-participants, randomized crossover trial. Participants had indwelling catheters placed for blood sampling and were fed a standardized breakfast, followed two hours later by a 250 kcal snack of either pecans or tortilla chips, and then by a self-selected lunch. Visual analog scale (VAS) appetite measures, blood markers, and energy expenditure were taken at intervals after food consumption. RESULTS: VAS ratings, energy, food intake and macronutrient composition did not differ between treatment conditions, but glucose and insulin were significantly more elevated after tortilla chips. Free fatty acids (FFA), triglycerides (TG), peptide YY (PYY), and glucagon-like peptide-1 (GLP-1) were higher after consuming pecans compared to tortilla chips. CONCLUSIONS: Pecan consumption improves postprandial glucose and insulin profiles which would be beneficial to individuals at risk of developing type 2 diabetes. Further studies are needed to investigate whether increased relative secretion of PYY and GLP-1 after eating pecans versus tortilla chips may affect subjective appetite and energy intake if consumed chronically.
Subject(s)
Appetite , Biomarkers , Cross-Over Studies , Energy Metabolism , Insulin , Obesity , Overweight , Snacks , Humans , Male , Female , Adult , Obesity/blood , Biomarkers/blood , Overweight/blood , Insulin/blood , Blood Glucose/metabolism , Glucagon-Like Peptide 1/blood , Middle Aged , Healthy Volunteers , Eating/physiology , Energy Intake , Dietary Carbohydrates/administration & dosage , Peptide YY/blood , Postprandial Period , Young AdultABSTRACT
The emptying rate of specific nutrients in enteral formulas is poorly understood, despite the importance of controlling the emptying rate in tube-fed patients. Because of their viscosity, thickened formulas are widely used to avoid gastric reflux and reduce the burden on caregivers. This study examined how thickeners in enteral formulas affected the gastric emptying rates of proteins and carbohydrates. A semi-dynamic gastric model was used to prepare and digest test enteral formulas that contained either no thickeners or agar (0.2%). The amounts of protein and carbohydrates in each emptied aliquot were determined, and the emptying rate was calculated. We found that agar accelerated protein emptying, and an exploratory experiment with agar (0.5%) suggested the possibility of concentration dependence. Additionally, experiments using gellan gum (0.08%), guar gum (0.2%), or carrageenan (0.08%, 0.2%) suggested that protein emptying could vary depending on the thickener type and that carrageenan might slow it. These results could help with the appropriate selection of thickeners added to liquid foods based on the patient's metabolic profile to manage nutrition, not only for tube-fed patients but also for those with oropharyngeal dysphagia or diabetes.
Subject(s)
Dietary Proteins , Enteral Nutrition , Food, Formulated , Galactans , Gastric Emptying , Mannans , Plant Gums , Gastric Emptying/drug effects , Enteral Nutrition/methods , Humans , Mannans/pharmacology , Mannans/administration & dosage , Viscosity , Galactans/pharmacology , Dietary Proteins/administration & dosage , Dietary Carbohydrates/administration & dosage , Carrageenan , Agar , Polysaccharides, Bacterial/pharmacology , Models, BiologicalABSTRACT
BACKGROUND: The sleep-low method has been proposed as a way to sleep in a low-glycogen state, increase the duration of low glycogen availability and sleep and temporarily restrict carbohydrates to improve exercise performance. However, long-term dietary restriction may induce mental stress in athletes. Therefore, if it can be shown that the effects of the sleep-low method can be achieved by restricting the carbohydrate intake at night (the nighttime carbohydrate restriction method), innovative methods could be developed to reduce weight in individuals with obesity and enhance athletes' performance with reduced stress and in a shorter duration when compared with those of previous studies. With this background, we conducted a study with the purpose of examining the intervention effects of a short-term intensive nighttime carbohydrate restriction method. METHODS: A total of 22 participants were recruited among university students participating in sports club activities. The participants were assigned at random to groups, including a nighttime carbohydrate restriction group of 11 participants (6 males, 5 females; age 22.3 ± 1.23) who started a carbohydrate-restricted diet and a group of 11 participants (5 males, 6 females; age 21.9 ± 7.9) who continued with their usual diet. The present study had a two-group parallel design. In the first week, no dietary restrictions were imposed on either group, and the participants consumed their own habitual diets. In the second week, the total amount of calories and carbohydrate intake measured in the first week were divided by seven days, and the average values were calculated. These were used as the daily calorie and carbohydrate intakes in the second week. Only the nighttime carbohydrate restriction group was prohibited from consuming carbohydrates after 4:00 p.m. During the two-week study period, all participants ran for one hour each day before breakfast at a heart rate of 65% of their maximum heart rate. RESULTS: The results obtained from young adults participating in sports showed significant differences in peak oxygen consumption (V·O2peak), work rate max, respiratory quotient (RQ), body weight and lean body mass after the intervention when compared with before the intervention in the nighttime carbohydrate restriction group (p < 0.05). CONCLUSIONS: Our findings suggest that the nighttime carbohydrate restriction method markedly improves fat metabolism even when performed for a short period. This method can be used to reduce body weight in individuals with obesity and enhance athletes' performance. However, it is important to consider the intake of nutrition other than carbohydrates.
Subject(s)
Diet, Carbohydrate-Restricted , Exercise , Humans , Male , Female , Young Adult , Diet, Carbohydrate-Restricted/methods , Adult , Exercise/physiology , Dietary Carbohydrates/administration & dosage , Lipid Metabolism/physiology , Sleep/physiology , Athletic Performance/physiology , Adolescent , Energy Intake , Time FactorsSubject(s)
Energy Intake , Humans , Nutrients , Adult , Longevity , Aged , Child , Dietary Proteins/administration & dosage , Middle Aged , Female , Dietary Carbohydrates/administration & dosage , Recommended Dietary Allowances , Male , AdolescentABSTRACT
Diabetes mellitus is a prevalent chronic autoimmune disease with a high impact on global health, affecting millions of adults and resulting in significant morbidity and mortality. Achieving optimal blood glucose levels is crucial for diabetes management to prevent acute and long-term complications. Carbohydrate counting (CC) is widely used by patients with type 1 diabetes to adjust prandial insulin bolus doses based on estimated carbohydrate content, contributing to better glycemic control and improved quality of life. However, accurately estimating the carbohydrate content of meals remains challenging for patients, leading to errors in bolus insulin dosing. This review explores the current limitations and challenges in CC accuracy and emphasizes the importance of personalized educational programs to enhance patients' abilities in carbohydrate estimation. Existing tools for assessing patient learning outcomes in CC are discussed, highlighting the need for individualized approaches tailored to each patient's needs. A comprehensive review of the relevant literature was conducted to identify educational programs and assessment tools dedicated to training diabetes patients on carbohydrate counting. The research aims to provide insights into the benefits and limitations of existing tools and identifies future research directions to advance personalized CC training approaches. By adopting a personalized approach to CC education and assessment, healthcare professionals can empower patients to achieve better glycemic control and improve diabetes management. Moreover, this review identifies potential avenues for future research, paving the way for advancements in personalized CC training and assessment approaches and further enhancing diabetes management strategies.
Subject(s)
Blood Glucose , Diabetes Mellitus, Type 1 , Dietary Carbohydrates , Humans , Dietary Carbohydrates/administration & dosage , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/drug therapy , Patient Education as Topic , Glycemic Control/methods , Insulin , Hypoglycemic Agents/administration & dosage , Quality of Life , MealsABSTRACT
BACKGROUND: Alkaloid- and polyphenol-rich white mulberry leaf and apple peel extracts have been shown to have potential glucose-lowering effects, benefitting the control of postprandial blood glucose levels. This study aimed to determine the effect of the combination of Malus domestica peel and Morus alba leaf extracts (GLUBLOCTM) on postprandial blood glucose and insulin-lowering effects in healthy adults after a carbohydrate-rich meal or sucrose drink intake. METHODS: This study was designed as a randomized, crossover, single-blinded clinical trial. Out of 116 healthy participants, 85 subjects (aged 18-60 years) completed the day 1 and 5 crossover study. On day 1, subjects were supplemented with a placebo or GLUBLOCTM tablet 10 min before the carbohydrate-rich meal (300 g of tomato rice) or sucrose drink intake (75 g of sucrose dissolved in 300 mL water). On day 5, the treatments were crossed over, and the same diet was followed. Postprandial blood glucose and insulin levels were measured on days 1 and 5 (baseline 0, post-meal 30, 60, 90, and 120 min). Differences in iAUC, Cmax, and Tmax were determined between the placebo and GLUBLOCTM-treated cohorts. RESULTS: Significant changes in total iAUC (0-120 min), Cmax, and Tmax of postprandial blood glucose and insulin levels were noticed upon GLUBLOCTM supplementation. The percentage reduction in the iAUC of blood glucose levels was 49.78% (iAUC0-60min) and 43.36% (iAUC0-120min), respectively, compared with the placebo in the sucrose drink intake study. Similarly, there was a 41.13% (iAUC0-60min) and 20.26% (iAUC0-120min) glucose-lowering effect compared with the placebo in the carbohydrate-rich meal intake study. CONCLUSIONS: Premeal supplementation with GLUBLOCTM significantly reduced the postprandial surge in blood glucose and insulin levels after a carbohydrate-rich meal or sucrose drink intake over 120 min in healthy individuals. This study proves that GLUBLOCTM can manage steady postprandial blood glucose levels.
Subject(s)
Blood Glucose , Cross-Over Studies , Dietary Carbohydrates , Dietary Supplements , Insulin , Morus , Plant Extracts , Postprandial Period , Humans , Adult , Insulin/blood , Blood Glucose/drug effects , Blood Glucose/metabolism , Male , Female , Plant Extracts/pharmacology , Plant Extracts/administration & dosage , Young Adult , Morus/chemistry , Middle Aged , Dietary Carbohydrates/administration & dosage , Single-Blind Method , Adolescent , Malus/chemistry , Sucrose , Plant Leaves/chemistry , Healthy Volunteers , Meals , BeveragesABSTRACT
Dietary nutrition plays a crucial role in determining pregnancy outcomes, with poor diet being a major contributor to pregnancy metabolic syndrome and metabolic disorders in offspring. While carbohydrates are essential for fetal development, the excessive consumption of low-quality carbohydrates can increase the risk of pregnancy complications and have lasting negative effects on offspring development. Recent studies not only highlighted the link between carbohydrate intake during pregnancy, maternal health, and offspring well-being, but also suggested that the quality of carbohydrate foods consumed is more critical. This article reviews the impacts of low-carbohydrate and high-carbohydrate diets on pregnancy complications and offspring health, introduces the varied physiological effects of different types of carbohydrate consumption during pregnancy, and emphasizes the importance of both the quantity and quality of carbohydrates in nutritional interventions during pregnancy. These findings may offer valuable insights for guiding dietary interventions during pregnancy and shaping the future development of carbohydrate-rich foods.
Subject(s)
Dietary Carbohydrates , Maternal Nutritional Physiological Phenomena , Pregnancy Outcome , Pregnancy , Female , Humans , Dietary Carbohydrates/administration & dosage , Pregnancy Complications , Diet, Carbohydrate-RestrictedABSTRACT
BACKGROUND AND OBJECTIVES: A sustained mismatch between energy intake (EI) and exercise energy expenditure (EEE) can lead to Low Energy Availability (LEA), as well as health and performance impairments characteristic of Relative Energy Deficiency in Sport (RED-S). Research in females has identified specific LEA cut-points for the risks of developing physiological and performance disturbances. Cut-points in males have yet to be evaluated; therefore, this study examined the prevalence of LEA in highly trained male cross-country skiers. The key purpose of this study was to analyze EI, resting energy expenditure (REE), EEE, and energy availability (EA) in highly trained cross-country skiers during the preparation and competition periods. The secondary objective of our study was to evaluate the relative contribution of fats and carbohydrates to EI, REE, and EEE. MATERIALS AND METHODS: EI was determined by an estimated 24 h diet recall method, REE was assessed by indirect calorimetry, and EEE was estimated from heart rate in 27 cross-country skiers. RESULTS: EI amounted to 4050 ± 797 kcal/day on a typical training day (TD) and 5986 ± 924 kcal/day (p < 0.001) on a typical competition day (CD). REE on TDs (2111 ± 294 kcal/day or 30 ± 6 kcal/day/kg) was higher (p < 0.05) than on CDs (1891 ± 504 kcal/day or 27 ± 7 kcal/day/kg). The EA in the athletes was <15 kcalâkg FFM-1·d-1 on TDs and <65 kcalâkg FFM-1·d-1 on CDs. EI was not optimal, as indicated by low EA throughout TDs (June). This could be associated with insufficient EI along with a high amount of EEE (3690.7 ± 485.2 kcal/day). During the transition from TD to CD, an increase in the contribution of fats to EI and EEE was observed in cross-country skiers. CONCLUSION: The conception of LEA and REDs and their potential implication for performance is underestimated among coaches and athletes. The importance of appropriate dietary strategies is essential to ensure that enough calories are consumed to support efficient training.
Subject(s)
Energy Intake , Energy Metabolism , Skiing , Humans , Skiing/physiology , Male , Energy Metabolism/physiology , Adult , Young Adult , Prevalence , Relative Energy Deficiency in Sport , Athletes/statistics & numerical data , Calorimetry, Indirect , Dietary Carbohydrates/administration & dosage , Dietary Fats/administration & dosage , Sports Nutritional Physiological Phenomena , Heart Rate/physiologyABSTRACT
Stearoyl-CoA desaturase-1 (SCD1) is a pivotal enzyme in lipogenesis, which catalyzes the synthesis of monounsaturated fatty acids (MUFA) from saturated fatty acids, whose ablation downregulates lipid synthesis, preventing steatosis and obesity. Yet deletion of SCD1 promotes hepatic inflammation and endoplasmic reticulum stress, raising the question of whether hepatic SCD1 deficiency promotes further liver damage, including fibrosis. To delineate whether SCD1 deficiency predisposes the liver to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC), we employed in vivo SCD1 deficient global and liver-specific mouse models fed a high carbohydrate low-fat diet and in vitro established AML12 mouse cells. The absence of liver SCD1 remarkably increased the saturation of liver lipid species, as indicated by lipidomic analysis, and led to hepatic fibrosis. Consistently, SCD1 deficiency promoted hepatic gene expression related to fibrosis, cirrhosis, and HCC. Deletion of SCD1 increased the circulating levels of Osteopontin, known to be increased in fibrosis, and alpha-fetoprotein, often used as an early marker and a prognostic marker for patients with HCC. De novo lipogenesis or dietary supplementation of oleate, an SCD1-generated MUFA, restored the gene expression related to fibrosis, cirrhosis, and HCC. Although SCD1 deficient mice are protected against obesity and fatty liver, our results show that MUFA deprivation results in liver injury, including fibrosis, thus providing novel insights between MUFA insufficiency and pathways leading to fibrosis, cirrhosis, and HCC under lean non-steatotic conditions.
Subject(s)
Carcinoma, Hepatocellular , Liver Cirrhosis , Liver Neoplasms , Stearoyl-CoA Desaturase , Stearoyl-CoA Desaturase/genetics , Stearoyl-CoA Desaturase/metabolism , Stearoyl-CoA Desaturase/deficiency , Animals , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/etiology , Mice , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/etiology , Liver Cirrhosis/genetics , Liver Cirrhosis/metabolism , Liver Cirrhosis/pathology , Liver Cirrhosis/etiology , Liver/metabolism , Liver/pathology , Lipogenesis/genetics , Osteopontin/genetics , Osteopontin/metabolism , Osteopontin/deficiency , Mice, Knockout , Male , Mice, Inbred C57BL , Dietary Carbohydrates/administration & dosage , Dietary Carbohydrates/adverse effects , HumansABSTRACT
BACKGROUND: Physique athletes are subjectively judged on their on-stage esthetic per their competition division criteria. To succeed, competitors look to acutely enhance their appearance by manipulating nutritional variables in the days leading up to competition, commonly referred to as peak week (PW). Despite their documented wide adoption, PW strategies lack experimental evidence. Further, the relationship between the specific strategies and the characteristics of the competitors who implement them are unknown. The aim of this research was to examine the effect of competitor characteristics on the specific nutritional peaking strategies implemented, the length of these strategies, and the range of daily carbohydrate (CHO) intakes during these strategies. METHODS: A 58-item survey was developed to gather information on peak week nutrition and training practices of physique athletes. A total of 160 respondents above the age of 18 who had competed in the last 5 years completed the nutrition section. The topics analyzed for this paper included competitor demographics, peaking strategies utilized, and PW CHO intakes. Competitor demographics are presented with the use of descriptive statistics. Associations between competitor demographics and peaking strategies implemented, peaking strategy length, and daily CHO intake ranges were assessed using multiple logistic regression, multiple ordinal logistic regression, and linear mixed models, respectively. RESULTS: From the sampled population, ages 24-39 years (71.2%), male (68.8%), natural (65%), and amateur (90%) were the most common characteristics from their respective categories, while mean competition preparation length was 20.35 ± 8.03 weeks (Males: 19.77 ± 7.56 weeks, Females: 21.62 ± 8.93 weeks), competition preparation body mass loss was 11.5 ± 5.56 kg (M: 12.7 ± 5.76 kg, F: 7.16 ± 3.99 kg), and competition body mass was 72.09 ± 15.74 kg (M: 80.15 ± 11.33 kg, F: 54.34 ± 7.16 kg). For males, the highest and lowest daily CHO intake during PW were 489.63 ± 224.03 g (6.22 ± 2.93 g/kg body mass) and 148.64 ± 152.01 g (1.94 ± 2.17 g/kg), respectively, while for females these values were 266.73 ± 131.23 g (5.06 ± 2.67 g/kg) and 94.42 ± 80.72 g (1.81 ± 1.57 g/kg), respectively. CHO back loading (45%) and water loading (40.6%) were the most popular peaking strategies, while the most prevalent peaking strategy length was 7 days (27.2%). None of the competitor characteristics predicted the use of CHO-based peaking strategies nor peaking strategy length. For non-CHO-based strategies, drug-enhanced competitors were more likely to restrict water than non-drug enhanced, while males and professional competitors had greater odds of loading sodium than females and amateurs, respectively. Finally, when comparing the disparity in highest and lowest CHO intakes during peak week, sex was the only significant factor. CONCLUSIONS: The results of this survey provide further information on the nutritional peaking strategies implemented by competitors. Certain characteristics were identified as predictors of sodium loading and water restriction, and the range of daily PW CHO intake. Contrastingly, no associations were found for CHO-based peaking strategies or peaking strategy length. While our analyses may be underpowered, and thus results should be interpreted with caution, it appears the nutritional peaking strategies implemented by physique competitors are seemingly complex and highly individual.
Subject(s)
Dietary Carbohydrates , Sports Nutritional Physiological Phenomena , Humans , Female , Male , Adult , Young Adult , Dietary Carbohydrates/administration & dosage , Athletes , Competitive Behavior/physiology , Surveys and Questionnaires , Athletic Performance/physiologyABSTRACT
In this article we present a protocol for the use of the low-FODMAP diet in paediatric patients and review of the current evidence on its efficacy. These short-chain carbohydrates, which can be fermented by the intestinal microbiota, are found in a wide variety of foods, mainly of plant origin. The low-FODMAP diet is a therapeutic tool used for the management of gastrointestinal disorders such as irritable bowel syndrome. The sources we used were PubMed, Web of Science, Google Scholar and institutional websites. Following consumption of FODMAP-rich foods, a series of end products are generated that are not absorbed, giving rise to symptoms. Before starting a low-FODMAP diet, it is important to carry out a diagnostic evaluation including any applicable tests. Treatment is structured in 3 phases: elimination, reintroduction and personalization phase. In the first phase, FODMAP-rich foods are eliminated for 2-3 weeks. In the second phase, lasting 8 weeks, FODMAP-rich foods are gradually reintroduced. The last phase consists in customizing the diet according to individual tolerance. This article details which foods contain FODMAPs and possible substitutes. In addition, specific food diary/intake tracking and educational materials are provided in a series of appendices to facilitate adherence to the diet. Although most studies have been conducted in adults, there is also some evidence on the beneficial effects in the paediatric age group, with a reduction of symptoms, especially in patients with functional gastrointestinal disorders. Nevertheless, more research is required on the subject.
Subject(s)
Gastrointestinal Diseases , Humans , Child , Gastrointestinal Diseases/diet therapy , Gastrointestinal Diseases/diagnosis , Gastrointestinal Diseases/therapy , Diet, Carbohydrate-Restricted/methods , Irritable Bowel Syndrome/diet therapy , Irritable Bowel Syndrome/diagnosis , Dietary Carbohydrates/administration & dosage , FODMAP DietABSTRACT
We studied the effect of separate and combined influence of chronic forced physical activity reduction and high-fat and high-carbohydrate diet containing cholesterol on some indicators of carbohydrate, lipid, and cholesterol metabolism in growing male Wistar rats. Used combination of factors simulating a sedentary lifestyle and unhealthy diet did not have a synergistic effect on the selected biomarkers. On the contrary, the effect was antagonistic: body weight and appetite decreased and insulin resistance increased. The obtained results indicate certain prospects of hypercholesterolemia model using in preclinical studies of specialized food products to optimize the diet of individuals with disorders of carbohydrate and lipid metabolism.
Subject(s)
Cholesterol , Diet, High-Fat , Lipid Metabolism , Rats, Wistar , Animals , Male , Rats , Diet, High-Fat/adverse effects , Lipid Metabolism/drug effects , Cholesterol/metabolism , Cholesterol/blood , Insulin Resistance , Body Weight/drug effects , Dietary Carbohydrates/administration & dosage , Dietary Carbohydrates/pharmacology , Hypercholesterolemia/metabolism , Hypercholesterolemia/diet therapy , Immobilization , Cholesterol, Dietary/administration & dosage , Appetite/drug effects , Appetite/physiology , Physical Conditioning, Animal/physiologyABSTRACT
The care needs of children and adolescents with type 1 diabetes and their families are frequently approached as if they were identical to those of adults, overlooking the distinct challenges young people may face. It has been stated that children and adolescents often find conventional conversations with diabetes specialists tiresome and unpleasant. The present study focuses on familial experiences of an advanced carbohydrate counting program tailored to children and adolescents. The data encompass semi-structured interviews with families who participated in a group-based child-centered advanced carbohydrate counting program. The analysis revealed five themes: (1) peer-to-peer interaction is an essential determinant of sharing and learning; (2) illness perception significantly influences dietary intake; (3) normalization of diabetes in everyday life eases the disease burden; (4) repetition of dietary knowledge is important for retention; and (5) creating a safe and playful learning environment is crucial to engaging children and adolescents in their own treatment. The present findings suggest that it would be beneficial to explore and consider alternative teaching approaches that are adapted to a more interactive and engaging learning environment that is specifically tailored to children and adolescents. This entails moving away from traditional individual approaches.