Effects of caffeine on human health

Effect of Caffeine on Colonic Manometry in Children

OBJECTIVES

Coffee and caffeinated products have been widely consumed for many centuries. Previous adult studies have suggested that both coffee and decaffeinated beverages induce colonic motility. However, no study has been conducted in pediatrics, and the role of caffeine alone in pediatric colonic motility needs to be explored.

METHODS

A prospective study of pediatric patients undergoing standard colonic motility testing that were able to consume caffeinated coffee, decaffeinated coffee, and caffeine tablet during colonic manometry. Patients who had a gastrocolonic reflex and high amplitude propagated contractions (HAPCs) in response to intraluminal administration of bisacodyl in the colon were included in the final analyses.

RESULTS

Thirty-eight patients were recruited, 22 of which were excluded, 11 due to abnormal studies (no HAPC seen in response to intraluminal response to bisacodyl), and 11 due to inability to consume all study agents or complete the study. Sixteen patients met criteria for final analyses. Intracolonic bisacodyl produced a larger area under the curve (AUC) compared to all other agents. Caffeinated coffee resulted in a higher AUC, motility index (MI), and time to HAPC compared with decaffeinated coffee ( P < 0.05). There was no significant difference between caffeinated coffee and caffeine tablet, or caffeine tablet and decaffeinated coffee.

CONCLUSIONS

Caffeine is indeed a colonic stimulant; however, other components of caffeinated and non-caffeinated beverages likely induce colonic response and require further evaluation for possible use as a colonic stimulant.

Caffeine levels and dietary intake in smokers with schizophrenia and bipolar disorder

Caffeine is one of the most widely used psychoactive drugs in the United States. High rates of caffeine use have been observed in adult smokers as well as those with serious mental illness. The current secondary analysis aimed to extend previous findings demonstrating high caffeine intake in schizophrenia by examining dietary intake of caffeine and serum caffeine levels in outpatient smokers with schizophrenia (SCZ), bipolar disorder (BP) and control smokers with no psychiatric diagnoses (CON). Two hundred forty-eight adult smokers (SCZ=80; BP=80; CON=88) were included in the current study. Adult smokers with schizophrenia, bipolar disorder, and no psychiatric diagnoses were 40.85 (SD = 11.90) years old on average and all participants were current smokers (∼20 cigarettes per day). Twenty-four hour self-reported caffeine intake (in mg) was highest among individuals with bipolar disorder (median=195.3), followed by adults with schizophrenia (median=155.0) and controls (median=131.7). Participants with bipolar disorder also had the highest serum caffeine levels (in ng/ml; median=1725), followed by those with schizophrenia (median=1194) and controls (median=613.2).  These results provide additional evidence of high caffeine intake among adults with schizophrenia and extend findings by identifying even higher rates of caffeine use in those with bipolar disorder. The current study suggests that caffeine intake is higher among subgroups of patients with serious mental illness.

Assessment of caffeine consumption behavior among Jazan University students in the south of Saudi Arabia: A cross-sectional study

Caffeine is a central nervous system stimulant. High consumption levels of caffeine can lead to intoxication and serious side effects. Saudi Arabia is witnessing a rise in the commercialization and consumption of caffeine. Young adults such as university students may exhibit high levels of caffeine consumption. This investigation aims to assess caffeine consumption habits among a sample of Jazan University students in the south of Saudi Arabia. This study was a cross-sectional investigation that utilized multistage sampling to recruit the students. Data was collected via a self-administered questionnaire that measured student demographics, their frequency of consuming caffeine-containing food, portion sizes, and patterns of consumption during different times of the day. Caffeine consumption levels were estimated based on a cutoff point of 400 mg per day. A chi-squared test was used to investigate the association between levels of caffeine consumption and measured study characteristics. A sample of 964 students was recruited with a mean age of 21.8 years. The most frequently consumed product among the recruited students was coffee (32%), followed by chocolate bars (16%) and soft drinks (12%). The median total consumed caffeine amount was 185 mg per day. 194 (20%) students of the sample exceeded the recommended level of daily caffeine consumption (>400 mg/day). Among the measured demographics, only the year of study was associated with caffeine consumption (P value of .003), suggesting that students in their earlier years of university are likely to exceed the recommended daily consumption of caffeine in comparison with those who are in their later years of study. Our investigation identified high levels of caffeine consumption among some students. The findings imply the need to enhance the awareness of students who exceed the recommended daily intake of caffeine regarding the harmful impacts of caffeine toxicity.

Prevalence of Voice Problems and Associated Risk Factors Among Tamil-Speaking Imams

PURPOSE

Voice of Professional Voice Users (PVUs) are of particular interest to practicing Speech-Language Pathologists. There is a dearth of studies concerning the prevalence of voice disorders and the associated risk factors among Tamil-speaking Imams. We address this research gap using non-experimental survey research.

METHODS

A questionnaire was framed by reviewing earlier literature. The derived questionnaire was administered to one hundred Tamil-speaking Imams actively involved in religious service in Tamil Nadu. We analyzed the obtained responses quantitatively and qualitatively. We also examined the effect of age on the prevalence of voice disorders and associated risk factors.

RESULTS

Based on survey responses, the career prevalence of voice problems among Tamil-speaking Imams was as high as 89%, and the point prevalence was 64%. The general health status of the Imams were good. However, vocal health was not satisfactory. This study identified several factors that contribute to voice problems, such as constant use of loud voice, acid reflux, unhealthy vocal habits, and insufficient hydration. A positive aspect observed during this study was the absence of smoking and consumption of alcohol among Imams. Even though the Imams presented good awareness of the voice production mechanism, they reported not seeking medical help when facing a voice problem. Current findings report a minimal impact of age-related differences on associated risk factors for voice disorders among the Imams.

CONCLUSIONS

Voice disorders are prevalent among Tamil-speaking Imams. Several risk factors leading to voice disorders among these individuals need to be addressed.

Intake of Food Supplements, Caffeine, Green Tea and Protein Products among Young Danish Men Training in Commercial Gyms for Increasing Muscle Mass

Sixty-three men (15-35 years of age) regularly training in Danish gyms and supplement users were interviewed about the use of supplemental protein and food supplements, intake of caffeine- and (-)-epigallocathechin-3-gallate (EGCG)-containing supplements and beverages and any experienced adverse effects. Protein powder (60%), fish oil (54%) and multivitamin/mineral supplements (41%) were the most popular products. The daily supplementary protein intake (mean 0.42 g/kg body weight, users only) in adult men contributed substantially to their protein intake and exceeded the recommended allowance (0.83 g/kg body weight) for six adult participants (14%). Thirty-eight percent of the adult men exceeded the daily caffeine intake presumed to be safe (400 mg) with coffee as the main contributor. Thirty percent drank green tea and among this percentage, two participants had an extreme daily intake (1.5 and 2 -L). EGCG intake could not be estimated from the food supplements due to the lack of label information. Eighteen participants (29%) reported having experienced adverse effects but seventeen did not consult a physician or report the adverse effect to the Danish food authority. The most common adverse effects were insomnia, shaking, headache and palpitations, itching of the skin and stinging. Pre-workout products accounted for 53% of the adverse effects. Three adverse effects came after intake of two brands of supplements known to have contained substances such as 1,3-dimethylamine or derivatives of phenylethylamines previously having caused serious adverse effects.

Association of urinary caffeine and caffeine metabolites with bone mineral density in children and adolescents

In epidemiological research, the link between coffee consumption and bone mineral density (BMD) is still debated. Moreover, there hasn't been any research on the relationship between urine caffeine and caffeine metabolites and BMD. This study aimed to investigate if there was a connection between urine caffeine and its metabolites and BMD in people between the ages of 8 and 19. Using data from the National Health and Nutrition Examination Survey 2009 to 2014, multivariate logistic regression models were utilized to investigate the association between urinary caffeine and caffeine metabolites and total BMD. Fitted smoothing curves and generalized additive models were also used. A total of 1235 adolescents were included in this analysis, after controlling for various variables, we found that the association between urinary theophylline and total BMD was negative, whereas the association between urinary paraxanthine, theobromine and caffeine and total BMD was positive. In our study, an inverted U-shaped association between urinary paraxanthine and urinary caffeine was found with BMD in women. In this cross-sectional study, the correlation between urinary caffeine and its metabolites and total BMD differed by sex and race. More studies are needed to confirm the results of this study and to investigate the underlying causes.

Risk or benefit? Side effects of caffeine supplementation in sport: a systematic review

PURPOSE

The aim of this study was to systematically review evidence on the prevalence and magnitude of side effects associated with caffeine supplementation in athletes.

METHODS

Systematic searches through the PubMed, VHL, Scopus, and Web of Science databases were conducted according to the PRISMA guidelines. Peer-reviewed articles written in English that reported the prevalence/percentage or magnitude/effect size of side effects after caffeine supplementation in athletes in a sports context were included. Studies were grouped by the dose of caffeine administered as follows: low =  ≤ 3.0 mg/kg; moderate = from 3.1 to 6.0 mg/kg; high =  ≥ 6.1 mg/kg. The magnitude of the side effects was calculated with effect sizes.

RESULTS

The search retrieved 25 studies that met the inclusion/exclusion criteria with a pooled sample of 421 participants. The supplementation with caffeine produced a higher prevalence or magnitude of all side effects under investigation when compared to placebo/control situations. The prevalence (magnitude) was between 6 and 34% (ES between 0.13 and 1.11) for low doses of caffeine, between 0 and 34% (ES between -0.13 and 1.20) for moderate doses of caffeine, and between 8 and 83% (ES between 0.04 and 1.52) with high doses of caffeine. The presence of tachycardia/heart palpitations and the negative effects on sleep onset had the highest prevalence and magnitude, in athletes using supplementation with caffeine.

CONCLUSION

In summary, caffeine supplementation in the doses habitually used to enhance physical performance produces several side effects, both after exercise and at least 24 h after the ingestion. However, the prevalence and magnitude of side effects with high doses of caffeine were habitually higher than with low doses of caffeine. From a practical perspective, using ~3.0 mg/kg of caffeine may be the dose of choice to obtain the ergogenic benefits of caffeine with the lowest prevalence and magnitude of side effects.

Recent Advances in Electrochemical Sensors for Caffeine Determination

The determination of target analytes at very low concentrations is important for various fields such as the pharmaceutical industry, environmental protection, and the food industry. Caffeine, as a natural alkaloid, is widely consumed in various beverages and medicines. Apart from the beneficial effects for which it is used, caffeine also has negative effects, and for these reasons it is very important to determine its concentration in different mediums. Among numerous analytical techniques, electrochemical methods with appropriate sensors occupy a special place since they are efficient, fast, and entail relatively easy preparation and measurements. Electrochemical sensors based on carbon materials are very common in this type of research because they are cost-effective, have a wide potential range, and possess relative electrochemical inertness and electrocatalytic activity in various redox reactions. Additionally, these types of sensors could be modified to improve their analytical performances. The data available in the literature on the development and modification of electrochemical sensors for the determination of caffeine are summarized and discussed in this review.

Caffeine-loaded nano/micro-carriers: Techniques, bioavailability, and applications

Caffeine, as one of the most consumed bioactive compounds globally, has gained considerable attention during the last years. Considering the bitter taste and adverse effects of high levels of caffeine consumption, it is crucial to apply a strategy for masking the caffeine's bitter taste and facilitating its programmable deliverance within a long time. Other operational parameters such as food processing parameters, exposure to sunlight and oxygen, and gastrointestinal digestion could also degrade the phenolic compounds in general and caffeine in special. To overcome these challenges, various nano/micro-platforms have been fabricated, including lipid-based (e.g., nanoliposomal vehicles; nanoemulsions, double emulsions, Pickering emulsions; microemulsions; niosomal vehicles; solid lipid nanoparticles and nanostructured lipid carriers), as well as biopolymeric (e.g., nanoparticles; hydrogels, organogels, oleogels; nanofibers and nanotubes; protein-polysaccharide nanocomplexes, conjugates; cyclodextrin inclusion complexes) and inorganic (e.g., gold and silica nanoparticles) nano/micro-structures. In this review, the findings on various caffeine-loaded nano/micro-carriers and their potential applications in functional food products/supplements will be discussed. Also, the controlled release and bioavailability of encapsulated caffeine will be given, and finally, the toxicity and safety of encapsulated caffeine will be presented.

Treatment of Lethal Caffeine Overdose with Haemodialysis: A Case Report and Review

Caffeine, chemically 1,3,7-trimethylxanthine, is the most widely consumed central nervous system stimulant in the world with pleiotropic effects on the cardiovascular, pulmonary, and renal systems. The advent of over the counter (OTC) caffeine formulations has opened the window for potential toxicity, either by inadvertent or intentional overdosing. We present the case of a patient who attempted suicide by caffeine overdose treated with emergent haemodialysis and a review of the literature.

Matrix-Specific Effects on Caffeine and Chlorogenic Acid Complexation in a Novel Extract of Whole Coffea arabica Coffee Cherry by NMR Spectroscopy

Coffee cherry is a rich source of caffeine and chlorogenic acids. In this study we investigate the structural analysis of caffeine-enriched whole coffee cherry extracts, CEWCCE by using ¹H and ¹³C NMR spectroscopy. The changes in ¹H chemical shift data in NMR spectra of CEWCCE compared to pure caffeine indicated the formation of complexes between caffeine and chlorogenic acids in aqueous solution. The effect of complexation on the peak position of caffeoylquinic acid and caffeine resonance with increasing addition of caffeine was investigated. 2D NOESY experiments show the presence of cross-peaks that are due to the proximity of chlorogenic acid and caffeine molecules in stable complexes in protic solvents. The quantification data of caffeine by ¹H qNMR was found to be in close agreement with the data obtained by HPLC analysis.

Caffeine consumption within British fencing athletes

The ergogenic effects of caffeine are well documented, yet despite the potential benefits of supplementation, there is a lack of understanding of caffeine habits and supplementation within fencing. British fencers (n = 136) completed a Web-based questionnaire, exploring self-reported caffeine consumption, reasons for use and education. Fencers (94.1%) habitually consumed caffeine, primarily due to the taste of the products (93.8%). Respondents ingested 183.4 ± 137.5 mg of caffeine daily, with a significant difference between age groups (p &lt; 0.05). Many respondents (30.1%) consumed caffeine 60 mins prior/during fencing training and/or competition with the main reason highlighted as cognitive performance enhancement. Respondents ingested 140.8 ± 104.6 mg of caffeine during training/competition, mainly as energy drinks, bars, and powders. Education on caffeine supplementation was low (25.7%), with significant associations between age groups (p &lt; 0.05). Evidence implies caffeine toxicity has been experienced by 35% of fencers, highlighting the need for education on caffeine consumption. To conclude there is evidence of caffeine supplementation in fencing, primarily to magnify cognitive performance. However, there is a requirement for targeted education on caffeine supplementation to fencers, so that negative side effects and potential anti-doping infringements can be avoided.

Anti-biofilm activity of caffeine against uropathogenic E. coli is mediated by curli biogenesis

Biofilms are assemblages of sessile microorganisms that form an extracellular matrix around themselves and mediate attachment to surfaces. The major component of the extracellular matrix of Uropathogenic E. coli and other Enterobacteriaceae are curli fibers, making biofilms robust and resistant to antimicrobials. It is therefore imperative to screen antibiofilm compounds that can impair biofilm formation. In the present study, we investigated the curli-dependent antibiofilm activity of caffeine against UPEC strain CFT073 and commensal strain E. coli K-12MG1655.Caffeine significantly reduced the biofilm formation of both UPEC and E. coli K-12 by 86.58% and 91.80% respectively at 48 mM caffeine as determined by Crystal Violet assay. These results were further confirmed by fluorescence microscopy and Scanning Electron Microscope (SEM). Caffeine significantly reduced the cytotoxicity and survivability of UPEC. Molecular docking analysis revealed a strong interaction between caffeine and curli regulator protein (Csg D) of E. coli. The qRT-PCR data also showed significant downregulation in the expression of CsgBA and the CsgDEFG operon at both 24 mM and 48 mM caffeine. The findings revealed that caffeine could inhibit E. coli biofilm formation by regulating curli assembly and thus may be used as an alternative therapeutic strategy for the treatment of chronic E. coli biofilm-related infections.

Enhanced decomposition of caffeine by water plasma combined with mist generator: Effect of operational parameter and decomposition pathway

Water plasma coupled with mist generator was introduced to perform the decomposition of caffeine (CAF) wastewater. The mist-shaped water molecule was directly used for plasma-forming gas with no additional gas. The influence of arc current on the decomposition of CAF was elucidated in detail. With the increase of input power from 0.8 to 1.1 kW according to arc current, the removal efficiency of total organic carbon (TOC) and CAF increased, reaching 91.1 and 99.8% at 9.5 A, respectively. H₂, CO, CO₂, and N₂ were major effluent gaseous species, of which the H₂ generation was more than 40% for all conditions. The concentration of nitrate in the effluent liquids was the highest at 9.5 A due to a higher oxidation environment. The H, O, and OH as reactive species formed via the dissociation of water molecules were demonstrated, and the plasma temperatures were at over 5000 K. The detailed decomposition pathway was deduced based on eleven intermediate products identified in this process. Electron impact and hydroxyl radical were found to take leading roles in the decomposition of CAF.

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.

Dietary supplements for lipedema

Lipedema is a chronic disease that mostly manifests in females as the abnormal distribution of subcutaneous adipose connective tissue, usually coupled with bruising, pain, and edema. Lipedema molecular pathophysiology is currently not clear, but several studies suggest that genetics and hormonal imbalance participate in lipedema pathogenesis. Women with lipedema present in some cases with elevated body mass index, and the appearance of obesity in addition to lipedema, where the obesity can cause serious health issues as in lipedema-free individuals with obesity, such as diabetes and cardiovascular disorders. Unlike obesity, lipedema tissue does not respond well to diet or physical exercise alone. Therefore, in this review we discuss the effect of various dietary supplements that, along with diet and physical exercise, cause fat burning and weight loss, and which could potentially be important in the treatment of lipedema. Indeed, an effective fat burner should convert stored fats into energy, mobilize and break down triglycerides in adipocytes, boost metabolism and inhibit lipogenesis. Common ingredients of fat burning supplements are green tea, caffeine, chromium, carnitine, and conjugated linoleic acid. The use of fat burners could act synergistically with a healthy diet and physical exercise for decreasing adipose tissue deposition in patients with lipedema and resolve related health issues. The effects of fat burners in human studies are sometimes contradictory, and further studies should test their effectiveness in treating lipedema.

Caffeine. A critical review of contemporary scientific literature

Caffeine is a secondary metabolite extensively studied for its stimulatory properties and presumed association with specific pathologies. This alkaloid is typically consumed through coffee, tea, and other plant products but is also an additive in many medications and confectionaries. Nonetheless, despite its worldwide consumption and acceptance, there is controversial evidence as to whether its effects on the central nervous system should be interpreted as stimulatory or as an addiction in which typical withdrawal effects are canceled out with its daily consumption. The following discussion is the product of an extensive review of current scientific literature, which aims to describe the most salient topics associated with caffeine's purpose in nature, biosynthesis, metabolism, physiological effects, toxicity, extraction, industrial use and current plant breeding approaches for the development of new caffeine deficient varieties as a more economical option to the industrially decaffeinated coffees currently available to caffeine intolerant consumers. Keywords: biosynthesis, decaffeination, extraction, metabolism, physiological effects, plant breeding.

Association between Dietary Patterns and Physical Fitness among Chinese Children and Adolescents in Shaanxi Province

Background: This study aims to investigate the associations between dietary patterns (breakfast, egg, dairy products, and sugared beverage intake frequencies) and physical fitness among Chinese children and adolescents in Shaanxi Province. METHODS: Data were extracted from the Chinese National Survey on Students’ Constitution and Health (CNSSCH). The study ultimately included 7305 participants (48.4% male, 51.6% female) aged 6–22 in Shaanxi Province, China. Multiple linear regression was used to examine the association of the frequency of breakfast, egg, dairy product, and sugared beverage intakes with physical fitness. RESULTS: The frequency of breakfast, egg, and dairy product intakes were all independently and positively associated with the level of physical fitness. The frequency of sugared beverage intake was negatively associated with the level of physical fitness. CONCLUSION: Healthier dietary patterns (i.e., higher breakfast, egg, and dairy product intakes and lower sugared beverage intake) were associated with greater physical fitness. Specifically, maintaining a healthy dietary pattern of breakfast, egg, and dairy product intakes can positively affect the strength and endurance performance of children and adolescents. Increased dairy product intake plays a crucial part in boosting the physical fitness total scores of children and adolescents.

Subchronic toxicological evaluation of EnXtra™ (standardised extract of Alpinia galanga rhizome) in rats

OBJECTIVES

Alpinia galanga is a commonly used ingredient in Asian food and traditional medicine. But an extract of the rhizome had never been used commercially in food supplements and functional foods. There is some evidence of safety and tolerability in humans for a proprietary A. galanga rhizome extract (EnXtra™) and it is Generally Recognised as Safe (GRAS) in the US already. However, this botanical ingredient has not been evaluated for its subchronic toxicity in rats to confirm its safety in wider food applications.

METHODS

Sprague Dawley rats were orally administered the test item for 90 days by following OECD (Test Guideline: 408), with a recovery period of 28 days. Cumulative effects and No Observed Adverse Effect Level (NOAEL) were estimated. EnXtra™ was administered orally at 0, 1,000, 2,000 and 3,000 mg kg^-1 body weight (b. wt.) with additional vehicle and high dose recovery groups. Observations included clinical signs, haematology, clinical chemistry, gross pathology and histopathology.

RESULTS

On terminal sacrifice, no treatment-related adverse effects were observed viz., clinical signs, mortality, body weight changes and feed consumption parameters. Haematology, clinical biochemistry and thyroid hormone levels were within the normal range. Further, no treatment-related gross and microscopic pathological lesions were observed across the treatment groups.

CONCLUSIONS

Based on the results of the toxicological evaluation, NOAEL of A. galanga rhizome extract (AGRE) was fixed at 3,000 mg kg^-1 b. wt. per day and ADI of 1800 mg day^-1 in the case of humans.

Pharmacologic Management of Excessive Daytime Sleepiness

Excessive daytime sleepiness (EDS) is defined as "irresistible sleepiness in a situation when an individual would be expected to be awake, and alert." EDS has been a big concern not only from a medical but also from a public health point of view. Patients with EDS have the possibility of falling asleep even when they should wake up and concentrate, for example, when they drive, play sports, or walk outside. In this article, clinical characteristics of common hypersomnia and pharmacologic treatments of each hypersomnia are described.

Distribution and ecological risks of pharmaceuticals and personal care products with different anthropogenic stresses in a coastal watershed of China

The occurrences of pharmaceutical and personal care products (PPCPs) in both freshwater and sea have been widely reported. However, pollution control requires further information on riverine discharges with influence of land-based activities and associated risks to estuarine ecosystems. This study investigated the spatial occurrences and the relationship to sociodemographic parameters of 30 PPCPs in 67 rivers along the Bohai coastal region. The results showed that PPCPs were mainly deposited in aquatic phase, and the partitioning coefficient between water and sediment was highly determined by chemical properties. The levels of 30 PPCPs in rivers ranged from 8.33 to 894.48 ng/L, showing a large variance among regions. Caffeine, sulfamethoxazole, sulfamethazine, ofloxacin, anhydro-erythromycin, and trimethoprim were found to be the major pollutants. Multivariable analysis method was used to assess the correlation of PPCPs markers to socio-economic parameters. The results indicated that domestic emissions contributed most to the occurrences of PPCPs in the riverine water. Risk assessment result indicated that sulfamethoxazole, caffeine, tetracycline, and carbamazepine ranked top four with the highest risks to the most sensitive aquatic organisms. The results identified caffeine and carbamazepine with high detection frequency and concentration as the priority chemicals, while sulfamethoxazole and erythromycin should also be concerned due to their potential threats in specific rivers. This study provides valuable information for pollution control over PPCPs riverine discharges in estuarine regions.

Listening to 15 Hz Binaural Beats Enhances the Connectivity of Functional Brain Networks in the Mental Fatigue State—An EEG Study

Introduction: It is clear that mental fatigue can have many negative impacts on individuals, such as impairing cognitive function or affecting performance. The aim of this study was to investigate the role of sound interventions in combating mental fatigue. Method: The subjects were assessed on various scales, a psychomotor vigilance task (PVT) task, and a 3 min resting-state electroencephalogram (EEG), followed by a 20 min mental fatigue–inducing task (Time Load Dual Back, TloadDback), during which subjects in different condition groups listened to either 15 Hz binaural beats, 40 Hz binaural beats, relaxing music, or a 240 Hz pure tone. After the mental fatigue–inducing task, subjects were again assessed on various scales, a PVT task, and a 3 min resting-state EEG. Results: After the fatigue-inducing task, there was no significant difference between the four groups on the scales or the PVT task performance. In TloadDback, the accuracy rate of the 40 Hz binaural beats group and the relaxing music group decreased in the middle stage of the task, while the 15 Hz binaural beats group and the 240 Hz pure tone group remained unchanged in all stages of the task. The EEG results showed that after fatigue inducement, the average path length of the 15 Hz binaural beats group decreased, and local efficiency showed an increasing tendency, indicating enhanced brain network connectivity. Meanwhile, the 240 Hz pure tone group showed enhanced functional connectivity, suggesting a state of mental fatigue in the group. Conclusions: The results of this study show that listening to 15 Hz binaural beats is a proven intervention for mental fatigue that can contribute to maintaining working memory function, enhancing brain topological structure, and alleviating the decline in brain function that occurs in a mentally fatigued state. As such, these results are of great scientific and practical value.

Are Non-animal Systemic Safety Assessments Protective? A Toolbox and Workflow

An important question in toxicological risk assessment is whether non-animal new approach methodologies (NAMs) can be used to make safety decisions that are protective of human health, without being overly conservative. In this work, we propose a core NAM toolbox and workflow for conducting systemic safety assessments for adult consumers. We also present an approach for evaluating how protective and useful the toolbox and workflow are by benchmarking against historical safety decisions. The toolbox includes physiologically based kinetic (PBK) models to estimate systemic Cmax levels in humans, and 3 bioactivity platforms, comprising high-throughput transcriptomics, a cell stress panel, and in vitro pharmacological profiling, from which points of departure are estimated. A Bayesian model was developed to quantify the uncertainty in the Cmax estimates depending on how the PBK models were parameterized. The feasibility of the evaluation approach was tested using 24 exposure scenarios from 10 chemicals, some of which would be considered high risk from a consumer goods perspective (eg, drugs that are systemically bioactive) and some low risk (eg, existing food or cosmetic ingredients). Using novel protectiveness and utility metrics, it was shown that up to 69% (9/13) of the low risk scenarios could be identified as such using the toolbox, whilst being protective against all (5/5) the high-risk ones. The results demonstrated how robust safety decisions could be made without using animal data. This work will enable a full evaluation to assess how protective and useful the toolbox and workflow are across a broader range of chemical-exposure scenarios.

Beyond thirst: Cravings for non-alcoholic beverages including soft drink

Cravings for a range of substances including drugs, alcohol, and food have been shown to predict subsequent consumption or use. However, this link has not yet been systematically examined for beverages other than alcohol. The present study aimed to provide a comprehensive investigation of cravings for non-alcoholic beverages and their link to consumption. Participants were 128 undergraduate students (17-25 years) who completed a craving diary and daily consumption measure over a period of a week. Cravings were reported for a range of beverages, including tea, juice, and flavoured milk, but by far the most craved beverages were water, coffee, and soft drink. Stronger cravings were associated with a greater likelihood of drinking and drinking more of the craved beverage. This was particularly the case for soft drink. Unlike water, cravings for coffee and soft drink were triggered by factors other than thirst, and the number of cravings predicted the total amount drunk over the week. The findings demonstrate the existence of cravings for non-alcoholic beverages such as soft drink, and point to these cravings as a potential target for reducing consumption.

Effect of Coffee on Lipopolysaccharide-Induced Immortalized Human Oral Keratinocytes

Periodontitis is a common inflammatory disease that is strongly influenced by dietary habits. Coffee is one of the most common dietary components; however, current research on the relationship between coffee consumption and periodontitis, as well as its underlying mechanisms, is limited. Based on a previous report, caffeine (CA) and chlorogenic acid (CGA) were formulated into artificial coffee (AC) for this experiment. Cell viability, prostaglandin E2 release, Western blotting, cellular reactive oxygen species (ROS) production, and NF-E2-related factor 2 (Nrf2) translocation analyses were performed to explore the effects of AC on lipopolysaccharide (LPS)-induced immortalized human oral keratinocytes (IHOKs) and elucidate their underlying mechanisms. AC pretreatment attenuated LPS-induced inflammatory mediator release, ROS production, and nuclear factor kappa B translocation in IHOKs. CA and CGA promoted AMP-activated protein kinase phosphorylation and down-regulated the nuclear factor-κB pathways to exert anti-inflammatory effects. Additionally, CGA promoted Nrf2 translocation and heme oxygenase-1 expression and showed anti-oxidative effects. Furthermore, AC, CA, and CGA components showed synergistic effects. Thus, we predict that coffee consumption may be beneficial for alleviating periodontitis. Moreover, the main coffee components CA and CGA seem to play a synergistic role in periodontitis.

The Counteractive Effect of Self-Regulation-Based Interventions on Prior Mental Exertion: A Systematic Review of Randomised Controlled Trials

BACKGROUND

Many investigations have been performed on the effects of mental exertion that consumes self-regulatory resources and then affects physical and/or cognitive performance later on. However, the effect of manipulating self-regulation and interventions to attenuate this negative effect remains unclear. Moreover, there is continuous controversy regarding the resource model of self-regulation.

OBJECTIVE

We conducted a systematic review to assess the literature on manipulating self-regulation based on four ingredients (standard, monitoring, strength, and motivation) in order to counter mental exertion and improve physical and/or cognitive performance. The results provide more insight into the resource model.

METHOD

A thorough search was conducted to extract the relevant literature from several databases, as well as Google Scholar, and the sources from the references were included as grey literature. A self-regulation intervention compared to a control condition, a physical and/or cognitive task, and a randomised controlled trial were selected.

RESULT

A total of 39 publications were included. Regarding the four components of self-regulation, the interventions could mainly be divided into the following: (i) standard: implementation intervention; (ii) monitoring: biofeedback and time monitoring; (iii) strength: repeated exercise, mindfulness, nature exposure, and recovery strategies; (iv) motivation: autonomy-supportive and monetary incentives. The majority of the interventions led to significant improvement in subsequent self-regulatory performance. In addition, the resource model of self-regulation and attention-restoration theory were the most frequently used theories and supported relevant interventions.

CONCLUSION

In line with the resource model, manipulating the four components of self-regulation can effectively attenuate the negative influence of mental exertion. The conservation proposed in the strength model of self-regulation was supported in the current findings to explain the role of motivation in the self-regulation process. Future studies can focus on attention as the centre of the metaphorical resource in the model.

Participatory Assessment and Selection of Workforce Health Intervention Priorities for Correctional Supervisors

OBJECTIVE

A team of academics and unionized correctional supervisors collaborated to assess workforce health and determine intervention priorities using participatory methods and tools.

METHODS

Correctional supervisors took a web-based survey. Univariate and bivariate tests examined attitudes/behaviors, exposures, and outcomes most strongly associated with health; risk based on rank within chain-of-command; and health behaviors amenable to change. We used a voting process tool to prioritize intervention topics.

RESULTS

Some health behaviors and outcomes were poor (89% overweight/ obese, 41% poor-quality sleep). We also found favorable health behaviors (annual check-ups) and psychosocial conditions (meaningful work). Some health risks (excessive overtime) were not amenable to change or resisted acknowledgment (poor mental health). The team voted to develop interventions on sleep, mental health, and obesity.

CONCLUSIONS

Comprehensive health assessment informed the prioritization process, enabling the team to quickly reach consensus on intervention priorities.

Black coffee mitigates diethyl phthalate disrupted folliculogenesis, reduced gonadotropins, and ovarian lesions in female albino mice

Phthalates are multifunctional compounds with extensive applications and emerging environmental pollutants. Due to their ubiquity in the environment and unavoidable exposure to humans, concerns have been voiced about public health dangers. This study was aimed to explore the diethyl phthalate (DEP) toxicity and the potential protective effect of black coffee in female Swiss albino mice. Four-week-old mice, weighing 12 ± 1 g were segregated into five groups (n = 10), designated as G-I (without any treatment), G-II (treated with corn oil), G-III (exposed to 1.5 mg/g body wt. (B.W.) DEP), G-IV (received 2 μg/g B.W coffee), and G-V (co-administrated with 1.5 mg/g DEP and 2 μg/g B.W coffee). Before dose administration, the coffee extract was assessed for its antioxidant potential through FRAP, TPC, and GC-MS analyses. Respective phthalates/coffee doses were administrated orally, once a day for 8 weeks consecutively starting from the prepubescent stage. After 56 days, mice were acclimated for 4 days then dissected. Morphological assessments showed an irregular shape of the ovaries in DEP-treated mice as compared to the control. The average bodyweight of DEP-intoxicated mice (p ≤ 0.05) increased notably against control, while DEP plus coffee group showed a regular gain in the average weight of mice. The gonado-somatic index showed non-significant variations among all groups. Micrometric studies showed that the diameter of secondary follicles (115 µm) in the ovaries of DEP-exposed mice (p ≤ 0.001) decreased significantly as compared to control (204 µm); conversely, follicular diameter in the coffee control group (248) increased significantly. Serum FSH and LH levels were significantly increased in DEP-exposed mice with a noteworthy decrease in estrogen level while hormonal levels of all other groups were comparable to control. Histological sections of DEP-exposed mice ovaries showed anatomical disruptions contrary to other groups, which were comparable with control. Antioxidant potential was checked in ovaries homogenates; FRAP values showed a notable decrease in DEP group in comparison with the control group, in contrast to G-V, when DEP was co-administrated with coffee. This study concluded that black coffee has protective effect, against DEP-instigated reproductive toxicity in Swiss albino female mice.

Relationship of Daily Coffee Intake with Vascular Function in Patients with Hypertension

We evaluated the relationship of daily coffee intake with endothelial function assessed by flow-mediated vasodilation and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation in patients with hypertension. A total of 462 patients with hypertension were enrolled in this cross-sectional study. First, we divided the subjects into two groups based on information on daily coffee intake: no coffee group and coffee group. The median coffee intake was two cups per day in the coffee group. There were significant differences in both flow-mediated vasodilation (2.6 ± 2.8% in the no coffee group vs. 3.3 ± 2.9% in the coffee group, p = 0.04) and nitroglycerine-induced vasodilation (9.6 ± 5.5% in the no coffee group vs. 11.3 ± 5.4% in the coffee group, p = 0.02) between the two groups. After adjustment for confounding factors, the odds ratio for endothelial dysfunction (OR: 0.55, 95% CI: 0.32–0.95) and the odds ratio for vascular smooth muscle dysfunction (OR: 0.50, 95% CI: 0.28–0.89) were significantly lower in the coffee group than in the no coffee group. Next, we assessed the relationship of the amount of daily coffee intake with vascular function. Cubic spline curves revealed that patients with hypertension who drank half a cup to 2.5 cups of coffee per day had lower odds ratios for endothelial dysfunction assessed by flow-mediated vasodilation and vascular smooth muscle dysfunction assessed by nitroglycerine-induced vasodilation. Appropriate daily coffee intake might have beneficial effects on endothelial function and vascular smooth muscle function in patients with hypertension.

Time-resolved quantitative phosphoproteomics reveals cellular responses induced by caffeine and coumarin

Protein phosphorylation is a critical way that cells respond to external signals and environmental stresses. However, the patterns of cellular response to chemicals at different times were largely unknown. Here, we used quantitative phosphoproteomics to analyze the cellular response of kinases and signaling pathways, as well as pattern change of phosphorylated substrates in HepG2 cells that were exposed to caffeine and coumarin for 10 min and 24 h. Comparing the 10 min and 24 h groups, 33 kinases were co-responded and 32 signaling pathways were co-enriched in caffeine treated samples, while 48 kinases and 34 signaling pathways were co-identified in coumarin treated samples. Instead, the percentage of co-identified phosphorylated substrates only accounted for 4.31% and 9.57% between 10 min and 24 h in caffeine and coumarin treated samples, respectively. The results showed that specific chemical exposure led to a bunch of the same kinases and signaling pathways changed in HepG2 cells, while the phosphorylated substrates were different. In addition, it was found that insulin signaling pathway was significantly enriched by both the caffeine and coumarin treatment. The pattern changes in phosphorylation of protein substrates, kinases and signaling pathways with varied chemicals and different time course shed light on the potential mechanism of cellular responses to endless chemical stimulation.

A double-blind, randomized, two-part, two-period crossover study to evaluate the pharmacokinetics of caffeine versus d9-caffeine in healthy subjects

The deuterium kinetic isotope effect has been used to affect the cytochrome P450 metabolism of the deuterated versions of substances. This study compares the pharmacokinetics of caffeine, a Generally Recognized As Safe food and beverage ingredient, versus d9-caffeine, a potential caffeine alternative, and their respective metabolites at two dose levels in 20 healthy adults. A single dose of 50 mg or 250 mg of caffeine, or a molar-equivalent dose of d9-caffeine, were orally administered in solution with blood samples collected for up to 48 h post-dose. Plasma concentrations of parent and metabolites were analyzed using validated LC-MS/MS methods. Both d9-caffeine and caffeine were rapidly absorbed; however, d9-caffeine exhibited a higher (ca. 29%-43%) C_max and 4-5-fold higher AUC_last than caffeine, and lower C_max, lower AUC_last, and a 5-10-fold reduction in the relative exposure to the active metabolites of caffeine. Results were consistent in normal and rapid metabolizers, and both substances were well tolerated.

Study on South African Indigenous Teas-Antioxidant Potential, Nutritional Content, and Hypoxia-Induced Cyclooxygenase Inhibition on U87 MG Cell Line

Background: This study comparatively assessed seven indigenous traditional tea plants on several attributes that included antioxidant, nutritional, caffeine contents, and cyclooxygenase activity. Methodology: Nutritional content of all tea plants were determined for energy, fat, carbohydrates, total sugars, dietary fiber and amino acids. Antioxidant potential and the antioxidant potentiating secondary metabolites were also measured and compared. Further, we investigated the tea plants for any role they would have on cyclooxygenase (COX) activity on cobalt chloride (CoCl₂) induced human glioma cell lines (U87MG). Results: The tea plants were found non-cytotoxic at concentrations tested against the human Chang liver and HeK 293 kidney cells and were found to be naturally caffeine free. The lowest and highest extraction yield among the tea plants was 7.1% for B. saligna and 15.48% for L. scaberrimma respectively. On average, the flavonol content was 12 to 8 QE/g, ORAC 800 µmol TE/g, TEAC 150 µmol TE/g, FRAP 155 µmol AAE/g, polyphenols 40 mg GAE/g, flavanols 0.35 mg CE/g, flavonols 12 mg QE/g and total flavonoid content (TFC) 180 µg QE/mg. The COX activity has been found to be inhibited by a dose-dependent manner by L. scaberrimma, B. saligna and L. javanica. Conclusion: The results further support competitive value of tea plants and need for improved and further development.

Caffeine and rheumatoid arthritis: A complicated relationship

The current ideal goal of rheumatoid arthritis (RA) management is to resolve joint and systemic inflammation by using pharmacological interventions, assuming this will correspondingly lead to overall well-being. Nonetheless, it has emerged that a substantial number of RA patients do not reach optimal disease control. Thus suggesting the holistic management of subjective symptoms might be overlooked. This poses significant medical challenges; hence the proposal of incorporating lifestyle interventions as part of a multidimensional approach. Among these aspects, both patients and physicians perceive the important role of nutrition. This review shall examine how caffeine, one of the most studied bioactive components of the most widely consumed beverages, may potentially interfere with RA management. In particular, the mechanism by which caffeine affects RA pathogenesis, as a trigger for RA onset or flare, including its influence on rheumatic drug metabolism and the most common RA comorbidities and constitutional symptoms are outlined, highlighting important knowledge gaps and unmet research needs.

Dietary sources, health benefits, and risks of caffeine

Dietary intake of caffeine has significantly increased in recent years, and beneficial and harmful effects of caffeine have been extensively studied. This paper reviews antioxidant and anti-inflammatory activities of caffeine as well as its protective effects on cardiovascular diseases, obesity, diabetes mellitus, cancers, and neurodegenerative and liver diseases. In addition, we summarize the side effects of long-term or excessive caffeine consumption on sleep, migraine, intraocular pressure, pregnant women, children, and adolescents. The health benefits of caffeine depend on the amount of caffeine intake and the physical condition of consumers. Moderate intake of caffeine helps to prevent and modulate several diseases. However, the long-term or over-consumption of caffeine can lead to addiction, insomnia, migraine, and other side effects. In addition, children, adolescents, pregnant women, and people who are sensitive to caffeine should be recommended to restrict/reduce their intake to avoid potential adverse effects.

Dietary Supplements for Weight Management: A Narrative Review of Safety and Metabolic Health Benefits

Dietary supplements for weight management include myriad ingredients with thermogenic, lipotropic, satiety, and other metabolic effects. Recently, the safety of this product category has been questioned. In this review, we summarize the safety evidence as well as relevant clinical findings on weight management and metabolic effects of six representative dietary supplement ingredients: caffeine, green tea extract (GTE), green coffee bean extract (GCBE), choline, glucomannan, and capsaicinoids and capsinoids. Of these, caffeine, GTE (specifically epigallocatechin gallate [EGCG]), and choline have recommended intake limits, which appear not to be exceeded when used according to manufacturers’ instructions. Serious adverse events from supplements with these ingredients are rare and typically involve unusually high intakes. As with any dietary component, the potential for gastrointestinal intolerance, as well as possible interactions with concomitant medications/supplements exist, and the health status of the consumer should be considered when consuming these components. Most of the ingredients reviewed also improved markers of metabolic health, such as glucose, lipids, and blood pressure, although the data are limited for some. In summary, weight management supplements containing caffeine, GTE, GCBE, choline, glucomannan, and capsaicinoids and capsinoids are generally safe when taken as directed and demonstrate metabolic health benefits for overweight and obese people.

Caffeine Intake among Undergraduate Students: Sex Differences, Sources, Motivations, and Associations with Smoking Status and Self-Reported Sleep Quality

Due to its stimulatory effects, caffeine is one of the most frequently consumed mood and behavior altering drugs. University students report using caffeine-containing products to enhance mood and performance or for a desire of alertness. The current study investigated caffeine consumption in university undergraduate students, and associations with smoking status, alcohol and cannabis consumption, fruit and vegetable consumption, and sleep quality. Motivations for caffeine intake were also ascertained. A total of 886 undergraduates aged 18−25 years from the University of the Balearic Islands participated in a cross-sectional survey. Caffeine was consumed by 91.1% of participants. Caffeine consumers were more likely to be female, smokers, and alcohol and cannabis consumers. Coffee was found to be the main source of caffeine intake in both men and women (48.9% of total caffeine intake). Higher percentages of women consumed coffee (56.4 vs. 42.1%, p = 0.01) and tea (40.3 vs. 19.8%, p < 0.001), whereas a higher percentage of men consumed energy drinks (18.0 vs. 7.4%, p < 0.001). Main motivations for caffeine intake were those related to cognitive enhancement. Caffeine intake was associated with poorer subjective sleep quality (p < 0.001). In conclusion, undergraduate students that were female and smokers reported higher caffeine intakes. Coffee was found as the main caffeine contributor, with higher contributions of tea in women and energy drinks in men. Universities should consider the implementation of health campaigns and educational programs to educate students of the risks of high caffeine consumption together with associated behaviors such as smoking, alcohol consumption and poor sleep quality to physical health and academic performance.

Prevalence of caffeine consumers, daily caffeine consumption, and factors associated with caffeine use among active duty United States military personnel

BACKGROUND

Although representative data on caffeine intake in Americans are available, these data do not include US service members (SMs). The few previous investigations in military personnel largely involve convenience samples. This cross-sectional study examined prevalence of caffeine consumers, daily caffeine consumption, and factors associated with caffeine use among United States active duty military service members (SMs).

METHODS

A stratified random sample of SMs were asked to complete an on-line questionnaire on their personal characteristics and consumption of caffeinated products (exclusive of dietary supplements). Eighteen percent (n = 26,680) of successfully contacted SMs (n = 146,365) completed the questionnaire.

RESULTS

Overall, 87% reported consuming caffeinated products ≥1 time/week. Mean ± standard error per-capita consumption (all participants) was 218 ± 2 and 167 ± 3 mg/day for men and women, respectively. Caffeine consumers ingested 243 ± 2 mg/day (251 ± 2 mg/day men, 195 ± 3 mg/day women). On a body-weight basis, men and women consumed respectively similar caffeine amounts (2.93 vs 2.85 mg/day/kg; p = 0.12). Among individual caffeinated products, coffee had the highest use (68%), followed by sodas (42%), teas (29%), energy drinks (29%) and gums/candy/medications (4%). In multivariable logistic regression, characteristics independently associated with caffeine use (≥1 time/week) included female gender, older age, white race/ethnicity, higher body mass index, tobacco use or former use, greater alcohol intake, and higher enlisted or officer rank.

CONCLUSION

Compared to National Health and Nutrition Examination Survey data, daily caffeine consumption (mg/day) by SMs was higher, perhaps reflecting higher mental and physical occupational demands on SMs.

Total 25(OH)D Concentration Moderates the Association between Caffeine Consumption and the Alkaline Phosphatase Level in Pregnant Women

The evidence as to whether caffeine consumption is beneficial or harmful to human health has been mixed. This study aimed to examine the effect of 25-hydroxyvitamin D (25(OH)D) concentration on the association between caffeine consumption and mineral metabolism in pregnant women. This is a cross-sectional study involving pregnant women at their 25th to 35th gestational week recruited at antenatal clinics in the period of July 2019 to December 2020. Peripheral blood samples were collected to determine their total 25(OH)D, albumin, alkaline phosphatase (ALP), calcium, phosphate, and ferritin level in serum. Questionnaires on demographics and dietary intake were also administered. Among 181 pregnant women recruited (Average age = 32.9 years), 50 (27.6%) of them were found to be vitamin D insufficient (25(OH)D concentration < 75 nmol/L), and 131 (72.4%) were vitamin D sufficient (25(OH)D concentration ≥ 75 nmol/L). Adjusted regression models identified an association between higher caffeine intake and lower ALP level only among vitamin D-sufficient pregnant women (β = −0.24, p = 0.006), but not in those with insufficient vitamin D (β = −0.02, p = 0.912). The findings provide new insights into 25(OH)D concentration as a potential modifier of the health effects of caffeine consumption during pregnancy.

Nutritional and Non-Nutritional Strategies in Bodybuilding: Impact on Kidney Function

Bodybuilders routinely engage in many dietary and other practices purported to be harmful to kidney health. The development of acute kidney injury, focal segmental glomerular sclerosis (FSGS) and nephrocalcinosis may be particular risks. There is little evidence that high-protein diets and moderate creatine supplementation pose risks to individuals with normal kidney function though long-term high protein intake in those with underlying impairment of kidney function is inadvisable. The links between anabolic androgenic steroid use and FSGS are stronger, and there are undoubted dangers of nephrocalcinosis in those taking high doses of vitamins A, D and E. Dehydrating practices, including diuretic misuse, and NSAID use also carry potential risks. It is difficult to predict the effects of multiple practices carried out in concert. Investigations into subclinical kidney damage associated with these practices have rarely been undertaken. Future research is warranted to identify the clinical and subclinical harm associated with individual practices and combinations to enable appropriate and timely advice.

The Impact of Caffeine Intake on Mental Health Symptoms in Postmenopausal Females with Overactive Bladder Symptoms: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Caffeine has been associated with a dose-dependent variety of mental health changes, which have been found to precede or be a complication of overactive bladder (OAB) symptoms after menopause. The current study examines the effects of low and moderate caffeine intake on anxiety, depression, sleep, and stress in postmenopausal females with OAB. Materials and Methods: Eighty-one females were randomized in a prospective, double-blind, placebo-controlled study. Participants were allocated to 200 mg/day caffeine, 400 mg/day caffeine, and placebo capsules for 1 week each in a crossover design and evaluated using validated mental health questionnaires. Symptoms during each treatment phase were measured using Beck Anxiety and Depression Inventory, Insomnia Severity Index, and Perceived Stress Scale. Linear regression models were used to examine the impact of low (200 mg/day) and moderate (400 mg/day) dose of caffeine and placebo on mental health. Results: Fifty-six female participants finished the study. The mean age was 69.2 years (58.0-84.0 years). Two females dropped out during the treatment phase with 400 mg/day caffeine intake due to side effects associated with headaches and nausea. Moderate dose of caffeine showed a small positive effect on mental health, specifically a decrease in anxiety during 7 days of exposure (p < 0.05). Conclusions: Moderate caffeine use may decrease anxiety in postmenopausal patients with underlying OAB, whereas depression, insomnia, and perceived stress were not affected by low-to-moderate caffeine intake. Our results support that counseling efforts on moderate caffeine consumption in postmenopausal patients underline that low-to moderate caffeine intake may be appropriate and possibly beneficial unless contraindicated due to other underlying conditions. Clinical Trials Registration: clinicaltrials.gov (NCT02180048).

Effects of Caffeinated Energy Drinks on Cardiovascular Responses during Exercise in Healthy Adults: A Systematic Review and Meta-analysis of Randomized Controlled Trials

The impact of caffeinated energy drinks (CED) on the cardiovascular (CV) response to exercise has not been well described. A systematic review and meta-analysis (MA) was conducted on the acute effects of CEDs on CV responses during dynamic, aerobic exercise in 296 healthy adult males (224) and females (72) in 21 randomized controlled trials. During exercise, there was an increase in heart rate (HR) (mean difference (MD), 2.86 bpm, 95% CI, 2.39-3.34 bpm, I2=0%, p<0.00001), and systolic blood pressure (SBP) (MD, 9.02 mmHg, 95% CI, 4.25-13.79 mmHg, I2= 0%, p=0.0002) with consumption of CEDs, compared to controls, but diastolic blood pressure was similar. Insufficient data was available to evaluate rate pressure product (HR X SBP) and exercise-induced arrhythmia. Though changes to HR during exercise were modest, the significant increase in exercise SBP highlights the importance of directly assessing CV effects of CEDs with exercise, especially in individuals prone to hypertension. Novelty Bullets: 1. Exercise SBP in healthy adults is significantly increased during exercise with the consumption of CEDs compared to control, despite limited data. 2. The direct assessment of CV effects of CEDs with exercise highlights the particular relevance to individuals prone to hypertension.

Application of the Solute-Solvent Intermolecular Interactions as Indicator of Caffeine Solubility in Aqueous Binary Aprotic and Proton Acceptor Solvents: Measurements and Quantum Chemistry Computations

The solubility of caffeine in aqueous binary mixtures was measured in five aprotic proton acceptor solvents (APAS) including dimethyl sulfoxide, dimethylformamide, 1,4-dioxane, acetonitrile, and acetone. The whole range of concentrations was studied in four temperatures between 25 °C and 40 °C. All systems exhibit a strong cosolvency effect resulting in non-monotonous solubility trends with changes of the mixture composition and showing the highest solubility at unimolar proportions of organic solvent and water. The observed solubility trends were interpreted based on the values of caffeine affinities toward homo- and hetero-molecular pairs formation, determined on an advanced quantum chemistry level including electron correlation and correction for vibrational zero-point energy. It was found that caffeine can act as a donor in pairs formation with all considered aprotic solvents using the hydrogen atom attached to the carbon in the imidazole ring. The computed values of Gibbs free energies of intermolecular pairs formation were further utilized for exploring the possibility of using them as potential solubility prognostics. A semi-quantitative relationship (R² = 0.78) between caffeine affinities and the measured solubility values was found, which was used for screening for new greener solvents. Based on the values of the environmental index (EI), four morpholine analogs were considered and corresponding caffeine affinities were computed. It was found that the same solute–solvent structural motif stabilizes hetero-molecular pairs suggesting their potential applicability as greener replacers of traditional aprotic proton acceptor solvents. This hypothesis was confirmed by additional caffeine solubility measurements in 4-formylmorpholine. This solvent happened to be even more efficient compared to DMSO and the obtained solubility profile follows the cosolvency pattern observed for other aprotic proton acceptor solvents.

The Effects of Light and the Circadian System on Rhythmic Brain Function

Life on earth has evolved under the influence of regularly recurring changes in the environment, such as the 24 h light/dark cycle. Consequently, organisms have developed endogenous clocks, generating 24 h (circadian) rhythms that serve to anticipate these rhythmic changes. In addition to these circadian rhythms, which persist in constant conditions and can be entrained to environmental rhythms, light drives rhythmic behavior and brain function, especially in nocturnal laboratory rodents. In recent decades, research has made great advances in the elucidation of the molecular circadian clockwork and circadian light perception. This review summarizes the role of light and the circadian clock in rhythmic brain function, with a focus on the complex interaction between the different components of the mammalian circadian system. Furthermore, chronodisruption as a consequence of light at night, genetic manipulation, and neurodegenerative diseases is briefly discussed.

Ocean Acidification, but Not Environmental Contaminants, Affects Fertilization Success and Sperm Motility in the Sea Urchin Paracentrotus lividus

Ocean acidification poses an increasing concern for broadcast spawning species that release gametes in the water column where fertilization occurs. Indeed, the functionality of gametes and their interactions may be negatively affected by reduced pH. Susceptibility to other environmental stressors, such as pollutants, may be also altered under acidified conditions, resulting in more detrimental effects. To verify this hypothesis, combined exposures to CO2-driven acidification and environmentally relevant concentrations (0.5 µg/L) of three contaminants (caffeine, diclofenac, and PFOS, all singularly or in mixture) were carried out to highlight potential negative effects on fertilization success and motility of sperm in the sea urchin Paracentrotus lividus. Our results showed a significant reduction in the percentage of fertilized eggs when sperm were pre-exposed to reduced pH (ambient pH minus 0.4 units) compared to that of controls (ambient, pH = 8.1). Sperm speed and motility also decreased when sperm were activated and then exposed at reduced pH. Conversely, at both pH values tested, no significant effect due to the contaminants, nor of their interaction with pH, was found on any of the biological endpoints considered.

Adverse effects associated with use of specific dietary supplements: The US Military Dietary Supplement Use Study

Dietary supplements (DSs) are used by 50% of Americans and 70% of United States military service members (SMs); some have adverse effects (AEs). This cross-sectional investigation examined AEs associated with specific DSs. A stratified random sample of SMs from the Air Force, Army, Marine Corps, and Navy was obtained. Volunteers completed a questionnaire reporting AEs for 96 generic and 62 specific DSs. The highest prevalence (≥1 AE) in specific DS categories was 35% prohormones, 33% weight loss supplements, 26% pre/post workout supplements, 14% herbal products, 12% multivitamin/multiminerals, 11% protein/amino acids, 9% muscle building supplements, 7% other DSs, 6% joint health products, and 5% individual vitamins/minerals. Specific DSs of concern (with proportion reporting AEs) included: Libido Max® (35%), Hydroxycut Hardcore® (33%), OxyElite® (33%), Roxylean® (31%), Growth Factor 9® (30%), Super HD® (29%), Hydroxycut Advanced® (29%), Lipo 6® (28%), The Ripper® (27%), Test Booster® (27%), Xenadrine Xtreme Thermogenic® (27%), C4 Extreme® (26%), and C4 Origional® (25%). Products marketed for weight loss, use before/after workout, and prohormones had the highest AE prevalence. DSs can contain substances with independent/additive AEs and/or interact with other ingredients or prescribed medications. Methods described here could provide a continuous surveillance system detecting dangerous DSs entering the market.

Effect of Caffeine Injection on Orthodontic Tooth Movement in Rats: An Experimental Study on Rats

OBJECTIVES

Several studies have investigated the effects of different medications on orthodontic tooth movement (OTM). This study assessed the effect of caffeine injection on OTM in rats.

MATERIALS AND METHODS

Thirty-five male Wistar rats were randomly divided into five groups. Their first molars and central incisors were attached with a nickel-titanium closed coil spring with 50 g load. The rats in the three experimental groups received 25, 50, and 75 mg/kg caffeine intraperitoneally for 21 days. The negative control group did not receive any injection and did not undergo orthodontic treatment. The positive control group underwent orthodontic treatment and received 0.9% NaCl (saline) injection. After 21 days, all rats were sacrificed by chloroform inhalation, and the maxilla was resected. The mean number of Howship's lacunae, blood vessels, osteoclasts, and root resorption lacunae was histologically measured. The bone volume-to-total volume ratio (BV/TV) in maxillary molars was calculated by microcomputed tomography (micro-CT) to quantify bone loss.

RESULTS

The amount of OTM and the number of osteoclasts, blood vessels, and Howship's lacunae significantly increased in rats under caffeine therapy, while the number of root resorption lacunae did not increase. Lower BV/TV in the caffeine groups was in accord with the increased count of osteoclasts.

CONCLUSION

Caffeine injection can significantly increase OTM in rats.

Effects of Caffeine Intake on Cardiopulmonary Variables and QT Interval after a Moderate-Intensity Aerobic Exercise in Healthy Adults: A Randomized Controlled Trial

Caffeine is considered a widely consumed natural and legal psychoactive stimulant with several effects on the body. The present study attempted to investigate the effects of caffeine consumed before and after a physical exercise on cardiovascular and cardiorespiratory functions in healthy adults. 36 healthy adult males were recruited and randomly allocated to one of the three (3) groups: group I (exercise without caffeine consumption), group II (caffeine beverage intake before exercise), and group III (caffeine beverage intake immediately after exercise). The heart rate (HR), QTc interval, blood pressure (BP), respiratory rate (RR), oxygen consumption (VO₂), and carbon dioxide emission (VCO₂) were measured at 0, 5, 10, and 15 min after the exercise. We observed a significant difference in all measured outcomes during the different recovery times in all the groups (p < 0.05). HR, RR, SBP, VO2, and VCO2 gradually decreased with time, DBP contrarily increased with time, and the QTc showed an irregular pattern. We can affirm that ingestion of caffeine before and after moderate aerobic exercise slows down the parasympathetic stimulation, heart rate recovery, and the recovery of HR and QTc with no major effects on BP, RR, VO₂, and VCO₂ in healthy adult men.

Active Women Across the Lifespan: Nutritional Ingredients to Support Health and Wellness

Women are the largest consumers of dietary supplements. Dietary supplements can play a role in health and performance, particularly for women. Growing evidence and innovations support the unique physiological and nutrient timing needs for women. Despite the need for more nutrition and exercise-specific research in women, initial data and known physiological differences between sexes related to the brain, respiration, bone, and muscle support new product development and evidence-based education for active women regarding the use of dietary supplements. In this narrative review, we discuss hormonal and metabolic considerations with the potential to impact nutritional recommendations for active women. We propose four potential areas of opportunity for ingredients to help support the health and well-being of active women, including: (1) body composition, (2) energy/fatigue, (3) mental health, and (4) physical health.