The publication data currently available has been vetted by Vanderbilt faculty, staff, administrators and trainees. The data itself is retrieved directly from NCBI's PubMed and is automatically updated on a weekly basis to ensure accuracy and completeness.
If you have any questions or comments, please contact us.
BACKGROUND - Epidemiologic evidence on dietary carbohydrates and stroke risk remains controversial. Very few prospective cohort studies have been conducted in Asian populations, who usually consume a high-carbohydrate diet and have a high burden of stroke.
OBJECTIVE - We examined dietary glycemic index (GI), glycemic load (GL), and intakes of refined and total carbohydrates in relation to risks of total, ischemic, and hemorrhagic stroke and stroke mortality.
DESIGN - This study included 64,328 Chinese women, aged 40-70 y, with no history of cardiovascular disease, diabetes, or cancer. A validated, interviewer-administered food-frequency questionnaire was used to assess usual dietary intakes at baseline and during follow-up. Incident stroke cases and deaths were identified via follow-up interviews and death registries and were confirmed by review of medical records and death certificates.
RESULTS - During mean follow-ups of 10 y for stroke incidence and 12 y for stroke mortality, we ascertained 2991 stroke cases (2750 ischemic and 241 hemorrhagic) and 609 stroke deaths. After potential confounders were controlled for, we observed significant positive associations of dietary GI and GL with total stroke risk; multivariable-adjusted HRs (95% CIs) for high compared with low levels (90th compared with 10th percentile) were 1.19 (1.04, 1.36) for GI and 1.27 (1.04, 1.54) for GL (both P-linearity < 0.05 and P-overall significance < 0.05). Similar linear associations were found for ischemic stroke, but the associations with hemorrhagic stroke appeared to be J-shaped. Similar trends of positive associations with stroke risks were suggested for refined carbohydrates but not for total carbohydrates. No significant associations were found for stroke mortality after multivariable adjustment.
CONCLUSION - Our results suggest that high dietary GI and GL, primarily due to high intakes of refined grains, are associated with increased risks of total, ischemic, and hemorrhagic stroke in middle-aged and older urban Chinese women.
© 2016 American Society for Nutrition.
PURPOSE - High digestible carbohydrate intakes can induce hyperglycemia and hyperinsulinemia and collectively have been implicated in colorectal tumor development. Our aim was to explore the association between aspects of dietary carbohydrate intake and risk of colorectal adenomas and hyperplastic polyps in a large case-control study.
METHODS - Colorectal polyp cases (n = 1,315 adenomas only, n = 566 hyperplastic polyps only and n = 394 both) and controls (n = 3,184) undergoing colonoscopy were recruited between 2003 and 2010 in Nashville, Tennessee, USA. Dietary intakes were estimated by a 108-item food frequency questionnaire. Unconditional logistic regression analysis was applied to determine odds ratios (OR) and corresponding 95 % confidence intervals (CI) for colorectal polyps according to dietary carbohydrate intakes, after adjustment for potential confounders.
RESULTS - No significant associations were detected for risk of colorectal adenomas when comparing the highest versus lowest quartiles of intake for total sugars (OR 1.03; 95 % CI 0.84-1.26), starch (OR 1.01; 95 % CI 0.81-1.26), total or available carbohydrate intakes. Similar null associations were observed between dietary carbohydrate intakes and risk of hyperplastic polyps, or concurrent adenomas and hyperplastic polyps.
CONCLUSION - In this US population, digestible carbohydrate intakes were not associated with risk of colorectal polyps, suggesting that dietary carbohydrate does not have an etiological role in the early stages of colorectal carcinogenesis.
FTO is the strongest known genetic susceptibility locus for obesity. Experimental studies in animals suggest the potential roles of FTO in regulating food intake. The interactive relation among FTO variants, dietary intake and body mass index (BMI) is complex and results from previous often small-scale studies in humans are highly inconsistent. We performed large-scale analyses based on data from 177,330 adults (154 439 Whites, 5776 African Americans and 17 115 Asians) from 40 studies to examine: (i) the association between the FTO-rs9939609 variant (or a proxy single-nucleotide polymorphism) and total energy and macronutrient intake and (ii) the interaction between the FTO variant and dietary intake on BMI. The minor allele (A-allele) of the FTO-rs9939609 variant was associated with higher BMI in Whites (effect per allele = 0.34 [0.31, 0.37] kg/m(2), P = 1.9 × 10(-105)), and all participants (0.30 [0.30, 0.35] kg/m(2), P = 3.6 × 10(-107)). The BMI-increasing allele of the FTO variant showed a significant association with higher dietary protein intake (effect per allele = 0.08 [0.06, 0.10] %, P = 2.4 × 10(-16)), and relative weak associations with lower total energy intake (-6.4 [-10.1, -2.6] kcal/day, P = 0.001) and lower dietary carbohydrate intake (-0.07 [-0.11, -0.02] %, P = 0.004). The associations with protein (P = 7.5 × 10(-9)) and total energy (P = 0.002) were attenuated but remained significant after adjustment for BMI. We did not find significant interactions between the FTO variant and dietary intake of total energy, protein, carbohydrate or fat on BMI. Our findings suggest a positive association between the BMI-increasing allele of FTO variant and higher dietary protein intake and offer insight into potential link between FTO, dietary protein intake and adiposity.
© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: email@example.com.
In dogs consuming a high-fat and -fructose diet (52 and 17% of total energy, respectively) for 4 wk, hepatic glucose uptake (HGU) in response to hyperinsulinemia, hyperglycemia, and portal glucose delivery is markedly blunted with reduction in glucokinase (GK) protein and glycogen synthase (GS) activity. The present study compared the impact of selective increases in dietary fat and fructose on liver glucose metabolism. Dogs consumed weight-maintaining chow (CTR) or hypercaloric high-fat (HFA) or high-fructose (HFR) diets diet for 4 wk before undergoing clamp studies with infusion of somatostatin and intraportal insulin (3-4 times basal) and glucagon (basal). The hepatic glucose load (HGL) was doubled during the clamp using peripheral vein (Pe) glucose infusion in the first 90 min (P1) and portal vein (4 mg·kg(-1)·min(-1)) plus Pe glucose infusion during the final 90 min (P2). During P2, HGU was 2.8 ± 0.2, 1.0 ± 0.2, and 0.8 ± 0.2 mg·kg(-1)·min(-1) in CTR, HFA, and HFR, respectively (P < 0.05 for HFA and HFR vs. CTR). Compared with CTR, hepatic GK protein and catalytic activity were reduced (P < 0.05) 35 and 56%, respectively, in HFA, and 53 and 74%, respectively, in HFR. Liver glycogen concentrations were 20 and 38% lower in HFA and HFR than CTR (P < 0.05). Hepatic Akt phosphorylation was decreased (P < 0.05) in HFA (21%) but not HFR. Thus, HFR impaired hepatic GK and glycogen more than HFA, whereas HFA reduced insulin signaling more than HFR. HFA and HFR effects were not additive, suggesting that they act via the same mechanism or their effects converge at a saturable step.
Copyright © 2014 the American Physiological Society.
The potential long-term association between carbohydrate intake and the risk of coronary heart disease (CHD) remains unclear, especially among populations who habitually have high-carbohydrate diets. We prospectively examined intakes of carbohydrates and staple grains as well as glycemic index and glycemic load in relation to CHD among 117,366 Chinese women and men (40-74 years of age) without history of diabetes, CHD, stroke, or cancer at baseline in Shanghai, China. Diet was assessed using validated food frequency questionnaires. Incident CHD cases were ascertained during follow-ups (in women, the mean was 9.8 years and in men, the mean was 5.4 years) and confirmed by medical records. Carbohydrate intake accounted for 67.5% of the total energy intake in women and 68.5% in men. Seventy percent of total carbohydrates came from white rice and 17% were from refined wheat products. Positive associations between carbohydrate intakess and CHD were found in both sexes (all P for heterogeneity > 0.35). The combined multivariate-adjusted hazard ratios for the lowest to highest quartiles of carbohydrate intake, respectively, were 1.00, 1.38, 2.03, and 2.88 (95% confidence interval: 1.44, 5.78; P for trend = 0.001). The combined hazard ratios comparing the highest quartile with the lowest were 1.80 (95% confidence interval: 1.01, 3.17) for refined grains and 1.87 (95% confidence interval: 1.00, 3.53) for glycemic load (both P for trend = 0.03). High carbohydrate intake, mainly from refined grains, is associated with increased CHD risk in Chinese adults.
Haploinsufficiency of the melanocortin-4 receptor (MC4R) results in melanocortin obesity syndrome, the most common monogenic cause of severe early onset obesity in humans. The syndrome, which produces measurable hyperphagia, has focused attention on the role of MC4R in feeding behavior and macronutrient intake. Studies show that inhibition of MC4R signaling can acutely increase the consumption of high-fat foods. The current study examines the chronic feeding preferences of mice with deletion of one or both alleles of the MC4R to model the human syndrome. Using two-choice diet paradigms with high-fat or high-carbohydrate foods alongside normal chow, we show, paradoxically, that deletion of one allele has no effect, whereas deletion of both alleles of the MC4R actually decreases preference for palatable high-fat and high-sucrose foods, compared with wild-type mice. Nonetheless, we observed hyperphagic behavior from increased consumption of the low-fat standard chow when either heterozygous or homozygous mutant animals were presented with dietary variety. Thus, decreased MC4R signaling in melanocortin obesity syndrome consistently yields hyperphagia irrespective of the foods provided, but the hyperphagia appears driven by variety and/or novelty, rather than by a preference for high-fat or high-carbohydrate foodstuffs.
RATIONALE - Respiratory syncytial virus (RSV) is an important cause of hospitalization and death in infants worldwide. Most RSV deaths occur in developing countries, where burden and risk factors for life-threatening illness are unclear.
OBJECTIVES - We defined the burden of life-threatening (O(2) saturation [O(2) sat] ≤ 87%) and fatal RSV infection, and characterized risk factors for life-threatening disease in hospitalized children. Special emphasis was placed on studying the impact of dietary habits during pregnancy. We hypothesized that dietary preferences, differing from those of our remote ancestors, would negatively impact children's pulmonary health. For instance, a diet rich in carbohydrates is a signature of recent millennia and typical of low-income populations, heavily burdened by life-threatening RSV disease.
METHODS - Prospective study in a catchment population of 56,560 children under 2 years of age during the RSV season in Argentina. All children with respiratory signs and O(2) sat less than 93% on admission were included.
MEASUREMENTS AND MAIN RESULTS - Among 1,293 children with respiratory infections, 797(61.6%) were infected with RSV: 106 of these had life-threatening disease; 1.9 per 1,000 children (95% confidence interval [CI], 1.5-2.2/1,000) under 24 months. A total of 22 hospitalized children died (9 RSV(+)), 26 died at home due to acute respiratory infection (14 attributed to RSV); all were under 12 months old. The annual attributable mortality rate for RSV was 0.7 per 1,000 infants (95% CI, 0.4-1.1/1,000). Life-threatening disease was dose-dependently associated with carbohydrate ingestion during pregnancy (adjusted odds ratio from 3.29 [95% CI, 1.15-9.44] to 7.36 [95% CI, 2.41-22.5] versus the lowest quartile).
CONCLUSIONS - Life-threatening and fatal RSV infections are a heavy burden on infants in the developing world. Diets rich in carbohydrates during pregnancy are associated with these severe outcomes.
PURPOSE - The purpose of this study is to describe the association between numeracy and self-reported dietary intake in patients with type 2 diabetes.
METHODS - Numeracy and dietary intake were assessed with the validated Diabetes Numeracy Test and a validated food frequency questionnaire in a cross-sectional study of 150 primary care patients enrolled in a randomized clinical trial at an academic medical center between April 2008 and October 2009. Associations between numeracy and caloric and macronutrient intakes were examined with linear regression models.
RESULTS - Patients with lower numeracy consumed a higher percentage of calories from carbohydrates and lower percentages from protein and fat. However, no differences in energy consumption or the percentage of energy intake owing to carbohydrates, fat, or protein were observed in adjusted analyses. Patients with lower numeracy were significantly more likely to report extremely high or low energy intake inconsistent with standard dietary intake.
CONCLUSIONS - Numeracy was not associated with dietary intake in adjusted analyses. Low numeracy was associated with inaccurate dietary reporting. Providers who take dietary histories in patients with diabetes may need to consider numeracy in their assessment of dietary intake.
Diet-induced obesity produces changes in endocannabinoid signaling (ECS), influencing the regulation of energy homeostasis. Recently, we demonstrated that, in high-fat-diet-fed rats, blockade of CB1 receptor by AM251 not only reduced body weight but also increased adult neurogenesis in the hippocampus, suggesting an influence of diet on hippocampal cannabinoid function. To further explore the role of hippocampal ECS in high-fat-diet-induced obesity, we investigated whether the immunohistochemical expression of the enzymes that produce (diacylglycerol lipase alpha and N-acyl phosphatidylethanolamine phospholipase D) and degrade (monoacylglycerol lipase and fatty acid amino hydrolase) endocannabinoids may be altered in the hippocampus of AM251 (3 mg/kg)-treated rats fed three different diets: standard diet (normal chow), high-carbohydrate diet (70% carbohydrate) and high-fat diet (60% fat). Results indicated that AM251 reduced caloric intake and body weight gain, and induced a modulation of the expression of ECS-related proteins in the hippocampus of animals exposed to hypercaloric diets. These effects were differentially restricted to either the 2-arachinodoyl glycerol or anandamide signaling pathways, in a diet-dependent manner. AM251-treated rats fed the high-carbohydrate diet showed a reduction of the diacylglycerol lipase alpha : monoacylglycerol lipase ratio, whereas AM251-treated rats fed the high-fat diet showed a decrease of the N-acyl phosphatidylethanolamine phospholipase D : fatty acid amino hydrolase ratio. These results are consistent with the reduced levels of hippocampal endocannabinoids found after food restriction. Regarding the CB1 expression, AM251 induced specific changes focused in the CA1 stratum pyramidale of high-fat-diet-fed rats. These findings indicated that the cannabinoid antagonist AM251 modulates ECS-related proteins in the rat hippocampus in a diet-specific manner. Overall, these results suggest that the hippocampal ECS participates in the physiological adaptations to different caloric diets.
© 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.
In order to explore the role of nutrients and bioactive related substances in colorectal cancer, we conducted a case-control in Uruguay, which is the country with the highest production of beef in the world. Six hundred and eleven (611) cases afflicted with colorectal cancer and 1,362 controls drawn from the same hospitals in the same time period were analyzed through unconditional multiple logistic regression. This base population was submitted to a principal components factor analysis and three factors were retained. They were labeled as the meat-based, plant-based, and carbohydrates patterns. They were rotated using orthogonal varimax method. The highest risk was positively associated with the meat-based pattern (OR for the highest quartile versus the lowest one 1.63, 95 % CI 1.22-2.18, P value for trend = 0.001), whereas the plant-based pattern was strongly protective (OR 0.60, 95 % CI 0.45-0.81, P value for trend <0.0001. The carbohydrates pattern was only positively associated with colon cancer risk (OR 1.46, 95 % CI 1.02-2.09). The meat-based pattern was rich in saturated fat, animal protein, cholesterol, and phosphorus, nutrients originated in red meat. Since herocyclic amines are formed in the well-done red meat through the action of amino acids and creatine, it is suggestive that this pattern could be an important etiologic agent for colorectal cancer.