Development of a Caffeine Content Table for Foods, Drinks, Medications and Supplements Typically Consumed by the Brazilian Population.

BACKGROUND: The lack of a national table informing the caffeine contents in foods, drinks, dietary supplements, and medications sold in Brazil added to the noncompulsory disclosure of caffeine contents on labels of food products makes it difficult to estimate caffeine consumption in the Brazilian population. Therefore, this study aimed to develop the Brazilian Caffeine Content Table (BraCaffT). METHODS: A systematic search for caffeine levels in foods, drinks, recipes, supplements, and medications was performed through a literature review, afterward collecting data from the United States Department of Agriculture Food Data Central, information from manufacturers' and websites, and the Brazilian official medication guide. Subsequently, data systematization was performed in a spreadsheet with standardized values presented in mg of caffeine per 100 g or 100 mL of food or drink and a capsule or pill for medications and some dietary supplements. RESULTS: The BraCaffT presents 57 items, divided into 11 categories: coffees, teas and infusions, cocoa powder, chocolates, cocoa-based beverages, desserts, soft drinks, energy drinks, guaraná powder, dietary supplements, and medications. CONCLUSIONS: The BraCaffT emerges as an instrument of great relevance and wide applicability in clinical contexts, in academic research, and as a database for the Brazilian population to better understand the amounts of caffeine in foods, drinks, dietary supplements, and medications consumed daily favoring a safe intake.

Acute Flaxseed Intake Reduces Postprandial Glycemia in Subjects with Type 2 Diabetes: A Randomized Crossover Clinical Trial.

Background: Postprandial glycemic excursions are associated with impairment control of diabetes mellitus. Long-term consumption of flaxseed can lower blood glucose levels; however, its effects on the postprandial glycemic response remain unknown. Therefore, this study aimed to evaluate the acute effects of raw flaxseed consumption on the 2 h postprandial glycemic curve in men with type 2 diabetes mellitus (T2DM). Methods: This was a randomized crossover clinical trial. Nineteen men with T2DM were randomly assigned a standardized breakfast without (control) or with a previous intake of 15 g of ground raw golden flaxseed (flax). Glycemia was measured at fasting and postprandial at 15, 30, 45, 60, 90, and 120 min. Palatability markers (visual appeal, smell, and pleasantness of taste) and taste intensity (sweetness, saltiness, bitterness, sourness, and creaminess) were evaluated. Results: The peak glucose rise and the 2 h AUC glycemic response reduced in the flax group by 17% (p = 0.001) and 24% (p < 0.001), respectively. The glucose peak time, palatability, and taste parameters did not differ between the two groups. Conclusions: Ingestion of 15 g of ground raw golden flaxseed before breakfast decreases the 2 h postprandial glycemic response in men with T2DM.

Can the Brazilian Caffeine Expectancy Questionnaires Differentiate the CYP1A2 and ADORA2A Gene Polymorphisms?-An Exploratory Study with Brazilian Athletes.

This study investigated the ability of the Brazilian Caffeine Expectancy Questionnaire (CaffEQ-BR), full and brief versions, to differentiate genetic profiles regarding the polymorphisms of the CYP1A2 (rs 762551) and ADORA2A (rs 5751876) genes in a cohort of Brazilian athletes. One-hundred and fifty participants were genotyped for CYP1A2 and ADORA2A. After the recruitment and selection phase, 71 (90% male and 10% female, regular caffeine consumers) completed the CaffEQ-BR questionnaires and a self-report online questionnaire concerning sociodemographic data, general health status, and frequency of caffeine consumption. The order of completion of the CaffEQ-BR questionnaires was counterbalanced. The concordance between the full and brief versions of the CaffEQ-BR was analyzed using the intraclass correlation coefficient (ICC). To determine the discriminatory capacity of the questionnaires for genotype, the receiver operating characteristic (ROC) curve was applied for sensitivity and specificity (significance level of 5%). Mean caffeine intake was 244 ± 161 mg·day−1. The frequency of AA genotypes for CYP1A2 was 47.9% (n = 34) and 52.1% (n = 37) for C-allele carriers (AC and CC). The frequencies of TT genotypes for ADORA2A were 22.7% (n = 15) and 77.3% (n = 51) for C-allele carriers (TC and CC). All CaffEQ-BR factors, for the full and brief versions, were ICCs > 0.75, except for factor 6 (anxiety/negative effects; ICC = 0.60), and presented ROC curve values from 0.464 to 0.624 and 0.443 to 0.575 for CYP1A2 and ADORA2A. Overall, the CaffEQ-BR (full and brief versions) did not show discriminatory capacity for CYP1A2 and ADORA2A gene polymorphisms. In conclusion, the CaffEQ-BR was not able to differentiate genotypes for the CYP1A2 or ADORA2A genes in this group of Brazilian athletes.

Impact of Gluten-Free Sorghum Bread Genotypes on Glycemic and Antioxidant Responses in Healthy Adults.

Sorghum is used to provide good quality gluten-free products due to phytochemicals and low glycemic index (GI). This study aimed to determine the chemical composition, the antioxidant activity and capacity, and the glycemic and insulinemic responses of gluten-free (GF) sorghum bread. GF bread samples were produced with three different sorghum genotypes. The samples were analyzed for chemical composition, resistant starch and dietary fiber content; antioxidant activity by ORAC; antioxidant capacity by FRAP; GI; and insulinemic responses. This double-blind, crossover, randomized clinical trial was conducted with 10 healthy men aged 28.0 ± 4.9 years (77.6 ± 11.7 kg and 24.2 ± 2.3 kg/m2). All sorghum bread showed significantly more fiber than rice bread (control). Brown sorghum bread was classified as low GI, bronze and white as medium GI, and control as high GI. Brown sorghum bread presented a low carbohydrate content, a significant amount of fiber, and a significantly lower 3 h AUC glucose response than those of the control, aside from the highest antioxidant activity value (p ≤ 0.001). Therefore, brown sorghum was superior to other genotypes analyzed in this study, and its production should be encouraged to provide gluten-free products with a better nutritional profile. More research is required to explore the effects of different sorghum genotypes in food products on human health.

Coffee Increases Post-Exercise Muscle Glycogen Recovery in Endurance Athletes: A Randomized Clinical Trial.

Coffee is one of the most widely consumed beverages worldwide and caffeine is known to improve performance in physical exercise. Some substances in coffee have a positive effect on glucose metabolism and are promising for post-exercise muscle glycogen recovery. We investigated the effect of a coffee beverage after exhaustive exercise on muscle glycogen resynthesis, glycogen synthase activity and glycemic and insulinemic response in a double-blind, crossover, randomized clinical trial. Fourteen endurance-trained men performed an exhaustive cycle ergometer exercise to deplete muscle glycogen. The following morning, participants completed a second cycling protocol followed by a 4-h recovery, during which they received either test beverage (coffee + milk) or control (milk) and a breakfast meal, with a simple randomization. Blood samples and muscle biopsies were collected at the beginning and by the end of recovery. Eleven participants were included in data analysis (age: 39.0 ± 6.0 years; BMI: 24.0 ± 2.3 kg/m2; VO2max: 59.9 ± 8.3 mL·kg-1·min-1; PPO: 346 ± 39 W). The consumption of coffee + milk resulted in greater muscle glycogen recovery (102.56 ± 18.75 vs. 40.54 ± 18.74 mmol·kg dw-1; p = 0.01; d = 0.94) and greater glucose (p = 0.02; d = 0.83) and insulin (p = 0.03; d = 0.76) total area under the curve compared with control. The addition of coffee to a beverage with adequate amounts of carbohydrates increased muscle glycogen resynthesis and the glycemic and insulinemic response during the 4-h recovery after exhaustive cycling exercise.

Caffeine Mouth Rinse Does Not Improve Time to Exhaustion in Male Trained Cyclists.

This study investigated the effects of caffeine mouth rinse on cycling time to exhaustion (TTE) and physiological responses in trained cyclists. In a double-blinded randomized counterbalanced cross-over design, 10 recreationally trained male cyclists (mean ± SD: 32 ± 3 years, 72.8 ± 5.3 kg, 1.78 ± 0.06 m, 13.9% ± 3.3% body fat, peak power output = 289.4 ± 24.7 W) completed two TTE tests cycling at 75% of peak aerobic power following 24 hr of dietary and exercise standardization. Cyclists were administered 25-ml mouth rinses for 5 s containing either 85 mg of caffeine or control (water) every 5 min throughout the exercise tests. No significant improvement in TTE was shown with caffeine mouth rinse compared with control (33:24 ± 12:47 vs. 28:08 ± 10:18 min; Cohen's dz effect size: 0.51, p = .14). Caffeine mouth rinse had no significant effect on ratings of perceived exertion (p = .31) or heart rate (p = .35) throughout the cycling TTE protocol. These data indicate that a repeated dose of caffeinated mouth rinse for 5 s does not improve cycling TTE in recreationally trained male cyclists. However, these findings should be taken with caution due to the small sample size and blinding ineffectiveness, while further well-design studies with larger samples are warranted.

Brief Version of Caffeine Expectancy Questionnaire in Brazil.

The use of extensive questionnaires has the limitation of filling time bias, related to the ability to focus and accurately respond to many items, justifying the necessity for a brief version. This study aimed to build a brief version of the Caffeine Expectancy Questionnaire in Brazil (B-CaffEQ-BR) composed of 21 items divided into seven factors, with as adequate consistency and reproducibility as the full version. Quantitative procedures using statistical modeling were applied using the CaffEQ-BR (full version) database keeping the Mean Absolute Error (MAE) (based on the full version) <0.5 and Cronbach's α and Intraclass Correlation Coefficient (ICC) ≥0.7. The expert panel (n = 3), in a blind design, evaluated the semantic structuring within the options indicated by previous statistical modeling until the agreement of the expert panel. The participants (n = 62), Brazilian adults who were regular caffeine consumers (175.8 ± 94.4 mg/day), of whom 62.9% were women, 33.1 ± 9.7 years, 24.5 ± 3.8 kg/m2, and 62.9% of whom self-identified as white, were asked to respond twice to the online questionnaire in 48-72 h. The first sample (n = 40) tested interobserver reproducibility with the double application of B-CaffEQ-BR. Another sample (n = 22) answered the CaffEQ-BR (full version) and B-CaffEQ-BR, and the last sample (n = 18) performed the reverse process. The B-CaffEQ-BR presented excellent internal consistency (Cronbach's α ≥ 0.729) and overall reproducibility (ICC ≥ 0.915) for the entire questionnaire and its seven factors. The B-CaffEQ-BR can be a valuable tool in caffeine research with the Brazilian adult population.

Novel insights on caffeine supplementation, CYP1A2 genotype, physiological responses and exercise performance.

Caffeine is a popular ergogenic aid due to its primary physiological effects that occur through antagonism of adenosine receptors in the central nervous system. This leads to a cascade of physiological reactions which increases focus and volition, and reduces perception of effort and pain, contributing to improved exercise performance. Substantial variability in the physiological and performance response to acute caffeine consumption is apparent, and a growing number of studies are implicating a single-nucleotide polymorphism in the CYP1A2 gene, responsible for caffeine metabolism, as a key factor that influences the acute responses to caffeine ingestion. However, existing literature regarding the influence of this polymorphism on the ergogenic effects of caffeine is controversial. Fast caffeine metabolisers (AA homozygotes) appear most likely to benefit from caffeine supplementation, although over half of studies showed no differences in the responses to caffeine between CYP1A2 genotypes, while others even showed either a possible advantage or disadvantage for C-allele carriers. Contrasting data are limited by weak study designs and small samples sizes, which did not allow separation of C-allele carriers into their sub-groups (AC and CC), and insufficient mechanistic evidence to elucidate findings. Mixed results prevent practical recommendations based upon genotype while genetic testing for CYP1A2 is also currently unwarranted. More mechanistic and applied research is required to elucidate how the CYP1A2 polymorphism might alter caffeine's ergogenic effect and the magnitude thereof, and whether CYP1A2 genotyping prior to caffeine supplementation is necessary.

Translation and Validation of the Caffeine Expectancy Questionnaire in Brazil (CaffEQ-BR).

Caffeine is the world's most commonly used stimulant of the central nervous system. Caffeine is present in coffee and other beverages such as tea, soft drinks, and cocoa-based foods. The caffeine expectancy questionnaire was developed to investigate the effects of caffeine expectations and thus contribute to knowledge about its usage and subjective effects (response expectancies). This study aimed to evaluate caffeine expectation psychometrically in a sample of the Brazilian population. The original version of the "Caffeine Expectancy Questionnaire (CaffEQ)" was translated and validated into Brazilian-Portuguese and adapted to Brazilian culture to be used in the Brazilian adult (19-59 y) population. After the translation and back-translation processes of the original CaffEQ questionnaire, the content and semantic validation were performed by a group of experts. The Brazilian-Portuguese version of the questionnaire consists of 47 items, in seven factors, which assess subjective perceptions about the effects of caffeine. Interobserver reproducibility and internal consistency of the questionnaire were tested with a convenience sample (n = 50) of Brazilian adult consumers of caffeine sources, who completed the Brazilian CaffEQ (CaffEQ-BR) on two occasions separated by 24 h. All of the 47 questions were adequate regarding reliability, clarity, and comprehension. Psychometric properties could be replicated consistently. Appropriate internal consistency and validation were confirmed by Cronbach's alpha (α) 0.948, and an intraclass correlation coefficient of 0.976 was observed. The CaffEQ-BR was applied using a web-based platform to a convenience sample of Brazilian adults from all 27 Brazilian states (n = 4202 participants), along with measures of sociodemographic and caffeine consumption data. Factor validity was verified by confirmatory factor analysis. The seven factors presented a good fit for Root Mean Square Error of Approximation-RMSEA = 0.0332 (95% CI: 0.0290-0.0375). By confirming the validity and reliability of CaffEQ-BR, a useful tool is now available to assess caffeine expectations in the Brazilian adult population.

Perception of Hunger/Satiety and Nutrient Intake in Women Who Regain Weight in the Postoperative Period After Bariatric Surgery.

OBJECTIVE: To investigate the perception of hunger and satiety and its association with nutrient intake in women who regain weight in the postoperative period after bariatric surgery. METHODS: Cross-sectional study of adult women divided into three groups: weight regain (n = 20), stable weight (n = 20) (both at least 24 months after Roux-en-Y gastric bypass surgery), and non-operated obesity (n = 20). A visual analogue scale measured hunger/satiety perception while fasting, immediately after finishing a test meal, and 180 min after finishing the test meal. The incremental area above or under the curve was calculated. Food intake was analyzed by 3 days of food recall and adjusted for intraindividual variation. To make between-group comparisons, Mann-Whitney, ANOVA, Kruskal-Wallis, and independent-samples T tests and Pearson's correlation were used. RESULTS: There were no between-group differences in incremental areas of hunger/satiety, but protein intake was significantly lower among patients who regained weight compared with those who had stable body weight (0.99 ± 0.23 g/kg body weight vs. 1.17 ± 0.21 g/kg body weight, p = 0.047). In the group that regained weight, satiety was correlated positively with usual dietary protein density (r = 0.541; p = 0.017) and negatively with usual carbohydrate intake (r = - 0.663; p = 0.002). CONCLUSION: Women who regained weight presented similar perceptions of hunger/satiety to those of patients without weight regain and with non-operated obesity. In patients who regained weight postoperatively, satiety perception was correlated positively with usual dietary protein density and inversely with usual carbohydrate intake.

Effects of Coffee Components on Muscle Glycogen Recovery: A Systematic Review.

Coffee is one of the most consumed beverages in the world, and it can improve insulin sensitivity, stimulating glucose uptake in skeletal muscle when adequate carbohydrate intake is observed. The aim of this review is to analyze the effects of coffee and coffee components on muscle glycogen metabolism. A literature search was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis, and seven studies were included, that explored the effects of coffee components on various substances and signaling proteins. In one of the studies with humans, caffeine was shown to increase glucose levels, Ca2+/calmodulin-dependent protein kinase phosphorylation, glycogen resynthesis rates, and glycogen accumulation after exercise. After intravenous injection of caffeine in rats, caffeine increased adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) phosphorylation, and glucose transport. In in vitro studies, caffeine raised AMPK and ACC phosphorylation, increasing glucose transport activity and reducing energy status in rat muscle cells. Cafestol and caffeic acid increased insulin secretion in rat beta cells and glucose uptake into human muscle cells. Caffeic acid also increased AMPK and ACC phosphorylation, reducing the energy status and increasing glucose uptake in rat muscle cells. Chlorogenic acid did not show any positive or negative effect. The findings from this review must be taken with caution due to the limited number of studies on the subject. In conclusion, various coffee components had a neutral or positive role in the metabolism of glucose and muscle glycogen, whereas no detrimental effect was described. Coffee beverages should be tested as an option for athletes' glycogen recovery.

Effects of caloric restriction and low glycemic index diets associated with metformin on glucose metabolism and cortisol response in overweight/obese subjects: a case series study.

BACKGROUND: To determine whether cortisol secretion and glucocorticoid receptors in lymphocytes and monocytes are altered in patients with impaired glucose tolerance, and whether treatment with a hypocaloric diet and metformin could interfere with these aspects. METHODS: This is an analytical, interventional, case series study. Patients with impaired glucose tolerance were included. They received 500 mg of metformin twice daily and followed a low glycemic index diet for 16 weeks. Cortisol levels were assessed at 8:00 A.M. before and after use of 0.25 mg of dexamethasone at 11:00 P.M. the day before. RESULTS: Sixteen subjects (9 men) were included. Normal basal levels of cortisol and adequate responses to the low dose of dexamethasone were observed before and after treatment. There was no significant correlation between the parameters evaluated and cortisol levels. Nevertheless, there was a strong correlation between the number of glucocorticoid receptors, BMI (r = 0.88; p = 0.02), and insulin AUC (r = 0.94; p = 0.005) before treatment; after treatment, all these associations ceased to exist. CONCLUSION: The cortisol secretion remained normal in the group of patients with impaired glucose tolerance. Treatment with metformin and diet did not change this condition. However, glucocorticoid receptor number had a strong correlation with insulin, due to insulin resistance, but this characteristic was lost after treatment.

Improved metabolic response after 16 weeks of calorie-restricted low-glycaemic index diet and metformin in impaired glucose tolerance subjects / Mejora de la respuesta metabólica después de 16 semanas de dieta con restricción calórica y bajo índice glucémico junto con metformina en sujetos con intolerancia a glucosa

Aim: This study analyzed the metabolic effects of dietary advice to follow calorie-restricted low-glycaemic index diet with metformin in overweight / obese impaired glucose tolerance subjects. Methods: Sixteen subjects with body mass index between 27-38 kg/m² were followed monthly for 16 weeks and treated with metformin (1 g/day) and dietary prescription for low-glycaemic index diet with energy reduction of 25-30% their total energy expenditure. Glucose metabolism, lipid profile, anthropometric and body composition, and food intake parameters were measured before and after the treatment. Paired t-tests/Wilcoxon tests were used to compare differences from baseline, with a statistical significance criterion of p ≤ 0.05. Results: There were significant reductions in anthropometric and body composition parameters, decrease in HOMA2-%β and triglycerides concentrations, and in - crease in Cederholm index. These results show enhanced peripheral insulin sensitivity and preservation of pan - creatic beta-cell function. Conclusion: Calorie-restricted low-glycaemic index diet and metformin was benefit to metabolic and anthropometric parameters in overweight/obese subjects with impaired glucose tolerance (AU)

Objetivo: Este estudio analizaba los efectos metabólicos del consejo dietético de seguir una dieta con restricción calórica y un índice glucémico bajo junto con Metformina en individuos con sobrepeso / obesidad y tolerancia alterada a la glucosa. Métodos: Se siguió mensualmente durante 16 semanas a 16 individuos con un índice de masa corporal entre 27-38 kg/m² y se les trató con Metformina (1 g/día) y una prescripción dietética con un índice glucémico bajo y una reducción del energía del 25-30 % de su gasto energético total. Se midieron el metabolismo de la glucosa, el perfil lipídico, la composición antropométrica y corporal y los parámetros de consumo de alimentos antes y después del tratamiento. Se emplearon las pruebas t pareadas y de Wilcoxon para comparar las diferencias con respecto al basal, con un criterio de significación estadística de p ≤ 0,05. Resultados: Hubo reducciones significativas en los parámetros de composición corporal y antropométricos, una disminución en las concentraciones de HOMA2-% y e triglicéridos y un aumento del índice de Cederholm. Estos resultados muestran una mejora de la sensibilidad periférica a la insulina y una conservación de la función de las células beta pancreáticas. Conclusión: la dieta con restricción calórica y un índice glucémico bajo junto con Metformina fueron beneficiosas para los parámetros metabólicos y antropométricos en individuos con sobrepeso/obesidad y una tolerancia a la glucosa alterada (AU)

Safety in the hypertriglyceridemia treatment with N-3 polyunsaturated fatty acids on glucose metabolism in subjects with type 2 diabetes mellitus.

INTRODUCTION: Type 2 diabetes mellitus increases the risk of hypertriglyceridemia and is an independent risk factor for cardiovascular diseases. Current literature reveals the beneficial effects of n-3 polyunsaturated fatty acids (n-3 PUFA) in hypertriglyceridemia treatment, however the safety for type 2 diabetic subjects are still debatable. This literature review discusses the safety on glucose metabolism of n-3 PUFA supplementation in the treatment of hypertriglyceridemia in subjects with type 2 diabetes mellitus. METHODS: A literature review was conducted on EMBASE and MEDLINE database to investigate clinical trials published since 1990 until June 2014 that investigated the effects of dietary/supplementation n-3 PUFA intake in hypertriglyceridemia treatment in subjects with type 2 diabetes mellitus. RESULTS AND DISCUSSION: Fourteen clinical trials (n = 2,105) were included in this review. All trials reported a reduction in triglycerides levels between 12 - 34% in intra- group and 15 - 36% in between-groups analysis. Four trials showed a significant increase in LDL-c (6 - 18%) and another four in HDL-c levels (4 - 15%). No significant changes were found to total cholesterol, VLDL-c, fasting glucose, HbA1C, and insulin sensitivity index. CONCLUSIONS: The n-3 PUFA supplementation leads an improvement on TG levels and did not result in any impairment on glucose metabolism in hypertriglyceridemic patients with type 2 diabetes mellitus being a safe option to treat the diabetic population.

Introducción: Diabetes mellitus tipo 2 aumenta el riesgo de hipertrigliceridemia y es un factor de riesgo independiente para las enfermedades cardiovasculares. La literatura actual revela efectos beneficiosos de n-3 ácidos grasos poliinsaturados (n-3 AGPI) en el tratamiento de la hipertrigliceridemia, sin embargo, la seguridad de este tratamento en los sujetos diabéticos tipo 2 es discutible. Esta revisión de la literatura discute la seguridad del n-3 PUFA la suplementación sobre el metabolismo de la glucosa en el tratamiento de la hipertrigliceridemia en pacientes con diabetes mellitus tipo 2. Métodos: Se ha realizado una revisión de la literatura en la base de datos MEDLINE y EMBASE del los ensayos clínicos publicados con fecha posterior al 1990 hasta Junio de 2014 sobre los efectos de la ingesta / suplementos del n-3 AGPI en el tratamiento de la hipertrigliceridemia en pacientes con diabetes mellitus tipo 2. Resultados y Discusión: Catorce estudios clínicos (n = 2105) se incluyeron en esta revisión. Del estudios informaron una reducción en los niveles de triglicéridos entre 12 a 34% en interior del grupo comparación y de 15 a 36% en entre grupos análisis. Cuatro estudios mostraron un aumento significativo en el LDL-c (6-18%) y otros cuatro en los niveles de HDL-c (4 - 15%). No se encontraron cambios significativos en el colesterol total, VLDL-c, la glucosa, HbA1c y el índice de sensibilidad a la insulina. Conclusión: El n-3 AGPI suplementación lleva una mejora en los niveles de triglicéridos y no arrojaron deterioro en el metabolismo de la glucosa en pacientes con hipertrigliceridemia con diabetes mellitus tipo 2 siendo una opción segura para el tratamiento de la población diabética.