Effect of the dietary supplement Meltdown on catecholamine secretion, markers of lipolysis, and metabolic rate in men and women: a randomized, placebo controlled, cross-over study

Genetically predicted basal metabolic rate and venous thromboembolism risk: a Mendelian randomization study

Background

Basal metabolic rate (BMR) is the minimum amount of energy needed by the body to carry out essential physiological functions. The goal of this study was to evaluate whether BMR causally influences venous thromboembolism (VTE) and its subtypes in European individuals.

Methods

A two-sample Mendelian randomization (MR) was performed. Within a genome-wide association study (GWAS) involving 454,874 people, genetic variants were chosen as instrumental variables based on their significant associations (p < 5 × 10-8) with BMR and their limited linkage disequilibrium (r2 < 0.001). The FinnGen project served as sources for summary statistics of VTE, encompassing different subtypes.

Results

Using the multiplicative random-effect inverse variance weighted method, our investigation revealed that one standard deviation higher BMR was associated with VTE (odds ratio [OR] = 1.684, 95% confidence interval [CI]: 1.465-1.936, p = 2.339 × 10-13), PE (OR = 1.824, 95% CI: 1.512-2.200, p = 3.399 × 10-10), and DVT of lower extremities (OR = 1.887, 95% CI: 1.562-2.280, p = 4.778 × 10-11). The consistency of these associations was observed in sensitivity analyses using various MR techniques like Mendelian randomization pleiotropy residual sum and outlier, MR-Egger, weighted median, and contamination mixture method. In addition, multivariable MR revealed direct effects of BMR on VTE and its subtypes when taking body mass index and current tobacco smoking into account.

Conclusion

Higher BMR may increase the risk of VTE and its subtypes including PE and DVT of lower extremities.

Effects of p-Synephrine during Exercise: A Brief Narrative Review

The p-synephrine is the principal phytochemical found in bitter orange (Citrus aurantium). This substance is widely included in dietary supplements for weight loss/body fat reduction due to its potential benefits of increasing fat oxidation. For years, p-synephrine-containing dietary supplements have been marketed without proper knowledge of their true effectiveness to enhance fat utilization, especially when combined with exercise. However, the effects of p-synephrine on fat oxidation during exercise have been investigated in the last few years. The aim of the current discussion is to summarize the evidence on the effects of p-synephrine intake on fat oxidation and performance during exercise. Previous investigations have demonstrated that the acute intake of p-synephrine does not modify running sprint performance, jumping capacity, or aerobic capacity. However, the acute intake of p-synephrine, in a dose of 2-3 mg/kg of body mass, has been effective to enhance the rate of fat oxidation during incremental and continuous exercise. This effect has been observed in a range of exercise workloads between 30% and 80% of peak oxygen uptake (VO_2peak). The p-synephrine has the ability to increase the maximal rate of fat oxidation during exercise of increasing intensity without affecting the workload at which maximal fat oxidation is obtained (Fatmax). The effect of p-synephrine on fat oxidation is normally accompanied by a concomitant reduction of carbohydrate utilization during exercise, without modifying the energy expended during exercise. The shifting in substrate oxidation is obtained without any effect on heart rate during exercise and the prevalence of adverse effects is negligible. Thus, the acute use of p-synephrine, or p-synephrine-containing products, might offer some benefits for those individuals seeking higher fat utilization during exercise at low to moderate intensities. However, more research is still necessary to determine if the effect of p-synephrine on fat oxidation during exercise is maintained with chronic ingestion, in order to ascertain the utility of this substance in conjunction with exercise programs to produce an effective body fat/weight loss reduction.

Effects of Bang® Keto Coffee Energy Drink on Metabolism and Exercise Performance in Resistance-Trained Adults: A Randomized, Double-blind, Placebo-controlled, Crossover Study

BACKGROUND

Energy drinks are often consumed by the general population, as well as by active individuals seeking to enhance exercise performance and augment training adaptations. However, limited information is available regarding the efficacy of these products. Thus, the purpose of this study was to determine the effects of a commercially available caffeine- and protein-containing energy drink on metabolism and muscular performance.

METHODS

Sixteen resistance-trained males (n = 8; mean ± SD; age: 22.4 ± 4.9 years; body mass: 78.8 ± 14.0 kg; body fat: 15.3 ± 6.4%) and females (n = 8; age: 24.5 ± 4.8 years; body mass: 67.5 ± 11.9 kg; body fat: 26.6 ± 7.1%) participated in this randomized, double-blind, placebo-controlled, crossover study. Following a familiarization visit, participants completed two identical visits to the laboratory separated by 5-10 days, each of which consisted of indirect calorimetry energy expenditure (EE) assessments before and after consumption of the beverage (Bang® Keto Coffee; 130 kcal, 300 mg caffeine, 20 g protein) or placebo (30 kcal, 11 mg caffeine, 1 g protein) as well as after exercise testing. In addition, participants' subjective feelings of energy, fatigue, and focus as well as muscular performance (leg press one-repetition maximum and repetitions to fatigue, maximal isometric and isokinetic squat testing) were assessed. Multiple repeated measures ANOVAs with Tukey post-hoc tests were used to analyze data. Estimates of effect size were quantified via partial eta squared (ηP2) and Hedge's g.

RESULTS

A significant interaction effect was identified for EE (p < 0.001, ηP2 = 0.52) but not respiratory exchange ratio (p = 0.17, ηP2 = 0.11). Following consumption of the beverage, EE was 0.18 [corrected]  kcal·min- 1 greater than placebo at the post-beverage time point (p < 0.001) and 0.08 [corrected]  kcal·min- 1 greater than placebo at the post-exercise time point (p = 0.011). However, no between-condition differences were detected for any subjective or muscular performance outcomes.

CONCLUSIONS

The results of this study suggest that consumption of the energy drink had minimal effects on lower-body muscular performance and subjective factors in the context of a laboratory setting. However, the beverage was found to significantly increase energy expenditure compared to placebo immediately following ingestion as well as during the recovery period after an exercise bout, suggesting that active individuals may improve acute metabolic outcomes via consumption of a caffeine- and protein-containing energy drink.

TRIAL REGISTRATION

This trial was prospectively registered at ClinicalTrials.gov (Identifier: NCT04180787 ; Registered 29 November 2019).

Caffeine Intake and Its Association with Body Composition Measures and Macronutrient Intakes in People Living with HIV in the Miami Adult Studies on HIV Cohort

Background: Caffeine acts as an anorexic agent, increases energy expenditures, and decreases total body fat mass, and could be detrimental to people living with HIV (PLWH). The objective of this study was to explore the relationship between caffeine consumption, body composition measures (fat mass, body mass index [BMI], and lean body mass [LBM]), nutrient intakes, CD4 counts, and HIV viral load in PLWH. Methods: A convenience sample of 130 PLWH was recruited and followed for 3 months. Caffeine intake, body composition measures, and nutrient intakes were collected using Modified Caffeine Consumption Questionnaire, bioimpedance analyses, and 24-hour dietary recalls. Linear regressions were used to analyze the baseline data for relationships between these variables. Linear mixed models (LMMs) were used to determine the overtime changes. Results: In baseline, linear regression analysis, higher caffeine consumption was associated with lower fat mass (β = -0.994, p = 0.042). However, BMI and LBM did not show any significant association with caffeine intake. LMM analysis showed that the association between caffeine intake and fat mass strengthened overtime (β = -1.987, p = 0.035). Baseline linear regression analysis showed that higher caffeine intake was significantly associated with lower caloric intakes from fat (β = -1.902, p = 0.044) and lower total caloric intake (β = -1.643, p = 0.042). However, LMM analysis showed that these associations diminished and lost significance overtime. There were no associations between body composition measures, nutrient intakes, CD4 counts, and HIV viral load. Conclusions: Caffeine intake adversely affected dietary intakes of macronutrients and total fat mass. Therefore, caffeine, a known anorectic, should be regulated in PLWH.

Safety, Efficacy, and Mechanistic Studies Regarding Citrus aurantium (Bitter Orange) Extract and p-Synephrine

Citrus aurantium L. (bitter orange) extracts that contain p-synephrine as the primary protoalkaloid are widely used for weight loss/weight management, sports performance, appetite control, energy, and mental focus and cognition. Questions have been raised about the safety of p-synephrine because it has some structural similarity to ephedrine. This review focuses on current human, animal, in vitro, and mechanistic studies that address the safety, efficacy, and mechanisms of action of bitter orange extracts and p-synephrine. Numerous studies have been conducted with respect to p-synephrine and bitter orange extract because ephedra and ephedrine were banned from use in dietary supplements in 2004. Approximately 30 human studies indicate that p-synephrine and bitter orange extracts do not result in cardiovascular effects and do not act as stimulants at commonly used doses. Mechanistic studies suggest that p-synephrine exerts its effects through multiple actions, which are discussed. Because p-synephrine exhibits greater adrenergic receptor binding in rodents than humans, data from animals cannot be directly extrapolated to humans. This review, as well as several other assessments published in recent years, has concluded that bitter orange extract and p-synephrine are safe for use in dietary supplements and foods at the commonly used doses. Copyright © 2017 The Authors Phytotherapy Research Published by John Wiley & Sons Ltd.

Effect of a Multi-Nutrient Over-the-Counter Supplement on Changes in Metabolic Rate and Markers of Lipolysis

Using a prospective, randomized, double-blind, crossover study design, fifteen healthy male (n = 8) and female (n = 7) participants (mean ± standard deviation (SD): 28.3 ± 6.1 yr, 176.3 ± 11.4 cm, 89.8 ± 21.7 kg, 28.5 ± 4.8 kg/m²) completed this study. Two testing sessions occurred after an overnight fast and refraining from physical exercise. Prior to and 60, 120, and 180 minutes after single dose ingestion of placebo (PLA) or a Thermogenic Supplement (TS), visual analog scales (VAS), resting metabolic rate (VO₂), and venous blood were collected. Resting heart rate and blood pressures were collected before, and 30, 60, 90, 120, 150 and 180 minutes after PLA or TS ingestion. Significant group × time interactions were found for VO₂ with TS experiencing significant (p < 0.05) increases 60 and 120 minutes after ingestion. Respiratory quotient values tended to be lower 180 minutes (p = 0.07) after TS ingestion. TS group reported increased energy 60 minutes (p < 0.05) after ingestion. No interactions were reported for resting heart rate or blood pressure. Significant within-group reductions in systolic blood pressure were noted for PLA, while resting heart rates were significantly lower in TS 30 and 60 minutes after ingestion. An interaction for epinephrine (p = 0.02) was found, while no changes were reported for norepinephrine and dopamine. Dependent t-tests using area under the curve calculations revealed higher AUC values for epinephrine in TS compared to PLA (p = 0.001). In conclusion, ingestion of a single dose of TS increased oxygen consumption, epinephrine and energy levels, while substrate oxidation tended to change in comparison to a placebo. No adverse responses were reported.

Effect of novel dietary supplement on metabolism in vitro and in vivo

Obesity is an increasingly prevalent and preventable morbidity with multiple behavioral, surgical and pharmacological interventions currently available. Commercial dietary supplements are often advertised to stimulate metabolism and cause rapid weight and/or fat loss, although few well-controlled studies have demonstrated such effects. We describe a commercially available dietary supplement (purportedly containing caffeine, catechins, and other metabolic stimulators) on resting metabolic rate in humans, and on metabolism, mitochondrial content, and related gene expression in vitro. Human males ingested either a placebo or commercially available supplement (RF) in a randomized double-blind placebo-controlled cross-over fashion. Metabolic rate, respiratory exchange ratio, and blood pressure were measured hourly for 3 h post-ingestion. To investigate molecular effects, human rhabdomyosarcoma cells (RD) and mouse myocytes (C2C12) were treated with various doses of RF for various durations. RF enhanced energy expenditure and systolic blood pressure in human males without altering substrate utilization. In myocytes, RF enhanced metabolism, metabolic gene expression, and mitochondrial content suggesting RF may target common energetic pathways which control mitochondrial biogenesis. RF appears to increase metabolism immediately following ingestion, although it is unclear if RF provides benefits beyond those provided by caffeine alone. Additional research is needed to examine safety and efficacy for human weight loss.

Natural Dietary and Herbal Products in Anti-Obesity Treatment

The prevalence of overweight and obesity is on the rise around the world. Common comorbidities associated with obesity, particularly diabetes, hypertension, and heart disease have an impact on social and financial systems. Appropriate lifestyle and behavior interventions are still the crucial cornerstone to weight loss success, but maintaining such a healthy lifestyle is extremely challenging. Abundant natural materials have been explored for their obesity treatment potential and widely used to promote the development of anti-obesity products. The weight loss segment is one of the major contributors to the overall revenue of the dietary supplements market. In this review, the anti-obesity effects of different dietary or herbal products, and their active ingredients and mechanisms of action against obesity will be discussed.

Capsaicinoids Modulating Cardiometabolic Syndrome Risk Factors: Current Perspectives

Capsaicinoids are bioactive nutrients present within red hot peppers reported to cut ad libitum food intake, to increase energy expenditure (thermogenesis) and lipolysis, and to result in weight loss over time. In addition it has shown more benefits such as improvement in reducing oxidative stress and inflammation, improving vascular health, improving endothelial function, lowering blood pressure, reducing endothelial cytokines, cholesterol lowering effects, reducing blood glucose, improving insulin sensitivity, and reducing inflammatory risk factors. All these beneficial effects together help to modulate cardiometabolic syndrome risk factors. The early identification of cardiometabolic risk factors can help try to prevent obesity, hypertension, diabetes, and cardiovascular disease.

Acute effectiveness of a "fat-loss" product on substrate utilization, perception of hunger, mood state and rate of perceived exertion at rest and during exercise

BACKGROUND

Achieving fat-loss outcomes by ingesting multi-ingredient mixtures may be further enhanced during exercise. This study tested the acute thermogenic effectiveness of a commercially available multi-ingredient product (Shred-Matrix®), containing Green Tea Extract, Yerba Maté, Guarana Seed Extract, Anhydrous caffeine, Saw palmetto, Fo-Ti, Eleuthero root, Cayenne Pepper, and Yohimbine HCI, on fatty acid oxidation (FAO), perception of hunger, mood state and rate of perceived exertion (RPE) at rest and during 30 min of submaximal exercise.

METHODS

Following institutional ethical approval, twelve healthy recreationally active participants, five females and seven males, were randomized to perform two separate experimental ergometry cycling trials, and to ingest 1.5 g (3 × capsules) of either a multi-ingredient supplement (SHRED) or placebo (PL). Participants rested for 3 h, before performing a 30-min cycling exercise corresponding to their individually-determined intensity based on their maximal fat oxidation (Fatmax). Fatty acid oxidation (FAO) was determined at rest, 3 h before exercise (Pre1), immediately before exercise (Pre2) and during exercise (Post), using expired gasses and indirect calorimetry. Rate of perceived exertion (RPE) was measured every 3 min during the 30-min exercise. Additionally both mood state and perception of hunger were assessed at Pre1, Pre2 and Post exercise. A repeated measures ANOVA design and Cohen's d effect sizes were used to analyze potential differences between times and treatment conditions.

RESULTS

FAO increased in SHRED from Pre1 to Pre2 [0.56 ± 0.26 to 0.96 ± 0.37, (p = 0.003, d =1.34)] but not in PL [0.67 ± 0.25 to 0.74 ± 0.19, (p = 0.334) d = 0.49], with no differences were found between conditions (p = 0.12, d = 0.49). However, Cohen's d = 0.77 revealed moderate effect size in favor of SHRED from Pre to Post exercise. RPE values were lower in SHRED compared to Pl (p< 0.001). Mood state and perception of hunger were not different between conditions, with no interaction effects. However, a trend was shown towards improved satiety in SHRED compared with PL, [F(1,11) = 3.58, p = 0.085].

CONCLUSIONS

The multi-ingredient product's potential enhancement of FAO during exercise, satiety, and RPE reduction suggests an acute effectiveness of SHRED in improving the exercise-related fat loss benefits.

Effects of commercially available dietary supplements on resting energy expenditure: a brief report

Commercially available dietary products advertised to promote weight loss are an underresearched but heavily purchased commodity in the United States. Despite only limited evidence, interest in dietary supplements continues to increase. This work uniquely summarizes the current evidence evaluating the efficacy of several over-the-counter thermogenic products for their effects on resting energy expenditure. Currently, there is some evidence suggesting dietary products containing select ingredients can increase energy expenditure in healthy young people immediately following consumption (within 6 hours). It is unclear if supplement-induced increases in metabolic rate provide additional benefit beyond that provided by dietary constituents that contain similar ingredients. It is also unclear if dietary supplements are effective for weight loss in humans.

Acute oral intake of a higenamine-based dietary supplement increases circulating free fatty acids and energy expenditure in human subjects

Background

Higenamine, also known as norcoclaurine, is an herbal constituent thought to act as a beta-2 adrenergic receptor agonist—possibly stimulating lipolysis. It was the purpose of this study to determine the impact of a higenamine-based dietary supplement on plasma free fatty acids and energy expenditure following acute oral ingestion.

Methods

Sixteen healthy subjects (8 men; 26.1 ± 2.5 yrs; 8 women 22.4 ± 3.1 yrs) ingested a dietary supplement containing a combination of higenamine, caffeine (270 mg), and yohimbe bark extract or a placebo, on two separate occasions in a double-blind, randomized, cross-over design, separated by 6–8 days. Blood samples were collected immediately before ingestion, and at 30, 60, 120, and 180 minutes post ingestion, and analyzed for plasma free fatty acids (FFA) and glycerol. Breath samples were collected at the same times for a measure of kilocalorie expenditure and respiratory exchange ratio (RER) using indirect calorimetry. Heart rate and blood pressure were recorded at all times. Data collection occurred in the morning following a 10 hour overnight fast.

Results

A condition effect was noted for both FFA (p < 0.0001) and kilocalorie expenditure (p = 0.001), with values higher for supplement compared to placebo at 60, 120, and 180 minutes post ingestion. No statistically significant effects were noted for glycerol or RER (p > 0.05). A condition effect was noted for heart rate (p = 0.03) and systolic blood pressure (p < 0.0001), with values higher for supplement compared to placebo.

Conclusion

Ingestion of a higenamine-based dietary supplement stimulates lipolysis and energy expenditure, as evidenced by a significant increase in circulating FFA and kilocalorie expenditure. The same supplement results in a moderate increase in heart rate (~3 bpm) and systolic blood pressure (~12 mmHg), which is consistent with previous studies evaluating moderate doses of caffeine and yohimbine, suggesting that higenamine contributes little to the increase in these hemodynamic variables. These findings are in reference to young, healthy and active men and women.

Capsaicin and evodiamine ingestion does not augment energy expenditure and fat oxidation at rest or after moderately-intense exercise

Capsaicin and evodiamine are 2 thermogenic agents recognized for their ability to stimulate the sympathetic nervous system. We hypothesized that both capsaicin and evodiamine would be effective at increasing thermogenesis and lipid oxidation during rest and exercise. In a randomized, cross-over design, 11 men ingested 500 mg of cayenne pepper (1.25 mg capsaicin), 500 mg evodiamine, or placebo at rest following 30 minutes of energy expenditure assessment using open-circuit spirometry. Energy expenditure was assessed again prior to commencing approximately 30 minutes of treadmill exercise at 65% peak oxygen consumption. Energy expenditure was assessed for another 30 minutes of the post-exercise period. Heart rate, blood pressure, core temperature, and venous blood samples were obtained 30 minutes before supplement ingestion, 1 hour after supplement ingestion, immediately post-exercise, and 45 minutes post-exercise. Serum markers of lipid oxidation (glycerol, free fatty acids, glucose, epinephrine, and norepinephrine) were determined spectrophotometrically with enzyme-linked immunosorbent assay. Two-way analyses of variance with repeated measures were performed for each dependent variable (P ≤ .05) with Supplement and Test as main effects. Statistical analyses revealed significant main effects for Test for hemodynamics, energy expenditure, serum catecholamines, and markers of fat oxidation immediately post-exercise (P < .05). No significant interactions between Supplement and Test were noted for any criterion variable (P > .05). These results suggest that acute ingestion of 500 mg of cayenne (1.25 mg capsaicin) or evodiamine is not effective at inducing thermogenesis and increasing fat oxidation at rest or during exercise in men.

International Society of Sports Nutrition position stand: energy drinks

Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature on the safety and efficacy of the use of energy drinks (ED) or energy shots (ES). The ISSN has concluded the following. 1. Although ED and ES contain a number of nutrients that are purported to affect mental and/or physical performance, the primary ergogenic nutrients in most ED and ES appear to be carbohydrate and/or caffeine. 2. The ergogenic value of caffeine on mental and physical performance has been well-established but the potential additive benefits of other nutrients contained in ED and ES remains to be determined. 3. Consuming ED 10-60 minutes before exercise can improve mental focus, alertness, anaerobic performance, and/or endurance performance. 4. Many ED and ES contain numerous ingredients; these products in particular merit further study to demonstrate their safety and potential effects on physical and mental performance. 5. There is some limited evidence that consumption of low-calorie ED during training and/or weight loss trials may provide ergogenic benefit and/or promote a small amount of additional fat loss. However, ingestion of higher calorie ED may promote weight gain if the energy intake from consumption of ED is not carefully considered as part of the total daily energy intake. 6. Athletes should consider the impact of ingesting high glycemic load carbohydrates on metabolic health, blood glucose and insulin levels, as well as the effects of caffeine and other stimulants on motor skill performance. 7. Children and adolescents should only consider use of ED or ES with parental approval after consideration of the amount of carbohydrate, caffeine, and other nutrients contained in the ED or ES and a thorough understanding of the potential side effects. 8. Indiscriminant use of ED or ES, especially if more than one serving per day is consumed, may lead to adverse events and harmful side effects. 9. Diabetics and individuals with pre-existing cardiovascular, metabolic, hepatorenal, and neurologic disease who are taking medications that may be affected by high glycemic load foods, caffeine, and/or other stimulants should avoid use of ED and/or ES unless approved by their physician.

Exposures to 1,3-dimethylamylamine-containing products reported to Texas poison centers

1,3-Dimethylamylamine (DMAA) is an ingredient in a number of weight loss and exercise performance enhancing products. However, information on the safety of DMAA-containing products is limited. Exposures to DMAA-containing products reported to Texas poison centers during 2010-2011 were identified and selected factors were examined. A total of 56 exposures were found, of which 75.0% were reported during 2011. OxyElite Pro™ was the reported product in 80.4% of the exposures. The patients were 51.8% male and 55.4% age ≤5 years. The patient was managed on site (such as at home) in 57.1% of the cases, and the exposure was known or expected to result in an outcome that was classified as not serious in 80.4%. The most frequently reported clinical effects were tachycardia (28.6%), nausea (16.1%), and vomiting (12.5%). The most common treatments were dilution (41.1%), food (19.6%), and activated charcoal (14.3%). It should be noted that the adverse clinical effects may be due to other ingredients in the DMAA-containing products, such as caffeine.

A review of the human clinical studies involving Citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine

This review summarizes the published as well as unpublished human studies involving Citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine, providing information and an assessment of the safety and efficacy of these widely used products. The results of over 20 studies involving a total of approximately 360 subjects that consumed p-synephrine alone or in combination with other ingredients are reviewed and critiqued. Over 50 % of the subjects involved in these studies were overweight/obese, and approximately two-thirds of these overweight/obese subjects consumed caffeine (132-528 mg/day) in conjunction with p-synephrine (10-53 mg/day). Bitter orange/p-synephrine containing products were consumed for up to 12 weeks. Approximately 44 % of the subjects consumed a bitter orange/p-synephrine only product, while the remainder consumed a complex product that contained multiple ingredients in addition to p-synephrine. In general, bitter orange extract alone (p-synephrine) or in combination with other herbal ingredients did not produce significant adverse events as an increase in heart rate or blood pressure, or alter electrocardiographic data, serum chemistry, blood cell counts or urinalysis. p-Synephrine alone as well as in combination products were shown to increase resting metabolic rate and energy expenditure, and modest increases in weight loss were observed with bitter orange extract/p-synephrine-containing products when given for six to 12 weeks. Longer term studies are needed to further assess the efficacy of these products and affirm their safety under these conditions.

Hemodynamic and hematologic profile of healthy adults ingesting dietary supplements containing 1,3-dimethylamylamine and caffeine

BACKGROUND

1,3-dimethylamylamine (a constituent of geranium), alone and in combination with caffeine, is widely used within dietary supplements. We have recently determined the hemodynamic effects of 1,3-dimethylamylamine and caffeine alone and in combination, using a single ingestion study. However, no study has determined the hemodynamic effects of these ingredients following chronic use. Moreover, no study has determined the effects of these ingredients on bloodborne variables related to health and safety. Therefore, the purpose of this investigation was to assess the hemodynamic and hematologic profile of two different dietary supplements containing 1,3-dimethylamylamine and caffeine (in addition to other ingredients), before and after two weeks of daily intake.

METHODS

7 men (24.9 ± 4.2 yrs) ingested the dietary supplement Jack3d™, while 4 men and 2 women (22.5 ± 1.8 yrs) ingested the dietary supplement OxyELITE Pro™ once per day for two weeks. On days 1 and 15, resting heart rate (HR), systolic (SBP), and diastolic (DBP) blood pressure were measured and rate pressure product (RPP) was calculated. Fasting blood samples were analyzed for complete blood counts, comprehensive metabolic panel, and lipid panel. These tests were done prior to ingestion of supplement. On days 1 and 15 following blood collection, subjects ingested the assigned supplement (2 servings) and HR, SBP, DBP, and RPP were recorded at 30, 60, 90, and 120 minutes post-ingestion.

RESULTS

After 14 days of treatment, resting HR, SBP, DBP, and RPP were not increased (P > 0.05). No significant changes were noted in any measured bloodborne variable, with the exception of an increase in fasting blood glucose with ingestion of Jack3d™ (P = 0.02). In response to acute intake of the supplements, HR, DBP, and RPP were not increased statistically (P > 0.05). SBP was increased with OxyELITE Pro™ (P = 0.03), but not with Jack3d™ (P = 0.09). Compared to pre-ingestion and in general, both supplements resulted in an increase in SBP, DBP, and RPP from 5%-15%, with a peak occurring at the 60 or 90 minute post-ingestion time.

CONCLUSION

Acute ingestion of OxyELITE Pro™, but not Jack3d™, results in an increase in SBP. Chronic intake of two servings per day of OxyELITE Pro™ or Jack3d™ over a 14 day period does not result in an elevation in resting HR, SBP, DBP, or RPP. No significant changes are noted in any measured bloodborne variable following 14 days of ingestion, with the exception of blood glucose with Jack3d™. Longer term intervention studies inclusive of larger sample sizes are needed to extend these findings.

A finished dietary supplement stimulates lipolysis and metabolic rate in young men and women

Background:

Dietary supplements are often marketed to increase lipolysis and thermogenesis, with the proposed end result being weight loss and body fat reduction. It was the purpose of the present investigation to study the acute effects of a weight/fat loss supplement within a sample of healthy human subjects.

Methods:

Twelve subjects (men 24.8 ± 4.3 yrs; women 22.8 ± 0.4 yrs) ingested a dietary supplement (OxyELITE Pro™) or a placebo, on two separate days in a double-blind, cross-over design. Blood samples were collected immediately before ingestion, and at 60 and 120 minutes post ingestion, and analyzed for plasma glycerol and free fatty acids (FFA). Breath samples were collected immediately before ingestion and at 30, 60, 90, and 120 minutes post ingestion, for a measure of kilocalorie expenditure using indirect calorimetry. Area under the curve (AUC) was calculated. Heart rate and blood pressure were recorded at all times and rate pressure product (RPP) was calculated.

Results:

AUC was greater for supplement compared to placebo for glycerol (22.74 ± 1.98 μg · mL⁻¹ · 2 hr⁻¹ vs. 15.76 ± 1.36 μg · mL⁻¹ · 2 hr⁻¹; P = 0.001), FFA (1.62 ± 0.07 mmol · L⁻¹_· 2 hr⁻¹ vs. 0.78 ± 0.12 mmol · L⁻¹ · 2 hr⁻¹; P < 0.0001), and kilocalorie expenditure (149 ± 7 kcal · 2 hr⁻¹ vs. 122 ± 8 kcal · 2 hr⁻¹; P = 0.005). Heart rate (P = 0.02), systolic blood pressure (P < 0.0001), and RPP (P = 0.002) were higher for supplement compared to placebo.

Conclusion:

Ingestion of OxyELITE Pro™ resulted in an increase in blood markers of lipolysis, as well as metabolic rate, during a two-hour post ingestion time period. An increase in hemodynamic variables was also observed. These findings are in reference to a sample of healthy men and women who were naïve to treatment with the dietary supplement. Additional work is needed to determine if the acute changes observed here would persist with chronic use of the supplement and possibly lead to weight/body fat loss over time.

Effects of 1,3-dimethylamylamine and caffeine alone or in combination on heart rate and blood pressure in healthy men and women

BACKGROUND

The use of 1,3-dimethylamylamine (geranamine), alone and in combination with caffeine, is becoming widespread within the dietary supplement industry. To our knowledge, no data are available concerning the effects of oral geranamine intake on heart rate (HR) and blood pressure in individuals.

METHODS

Ten young healthy men and women ingested 1 of 5 conditions on different days using a double-blind, randomized, crossover design. The following were ingested after a 10-hour overnight fast: 250 mg caffeine (C), 50 mg geranamine (G 50 mg), 75 mg geranamine (G 75 mg), 250 mg caffeine + 50 mg geranamine (C + G 50 mg), and 250 mg caffeine + 75 mg geranamine (C + G 75 mg). Heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), and rate pressure product (RPP) were measured pre-ingestion and at 30, 60, 90, and 120 minutes post-ingestion. Plasma norepinephrine (NE) and epinephrine (EPI) were measured pre-ingestion and at 60 and 120 minutes post-ingestion.

RESULTS

Heart rate was unaffected by treatment, but blood pressure and RPP were higher with geranamine, generally in a dose-dependent manner. The peak percent change from pre-ingestion in SBP (~20%), DBP (~17%), and RPP (~9%) was noted with C + G 75 mg at 60 minutes post-ingestion. Plasma NE and EPI were relatively unaffected by treatment.

CONCLUSION

We report for the first time that acute ingestion of 1,3-dimethylamylamine alone and in combination with caffeine results in an increase in SBP, DBP, and RPP without an increase in HR. The largest increase is observed at 60 minutes post-ingestion of C + G 75 mg. These changes cannot be explained by circulating NE and EPI.

Thermogenic effect of meltdown RTD energy drink in young healthy women: a double blind, cross-over design study

Background

The purpose of this study was to examine the acute metabolic effects of a high-energy drink in healthy, physically-active women.

Methods

Ten women (20.4 ± 0.70 y; 166.9 ± 7.2 cm; 67.0 ± 7.0 kg; 29.6 ± 6.5% body fat) underwent two testing sessions administered in a randomized and double-blind fashion. Subjects reported to the laboratory in a 3-hr post-absorptive state and were provided either 140 ml of the high-energy drink (SUP; commercially marketed as Meltdown RTD™) or placebo (P). Subjects consumed two 70 ml doses of SUP or P, separated by 30 min and rested in a semi-recumbent position for 3 hours. Resting oxygen consumption (VO₂) and heart rate (HR) were determined every 5 min during the first 30 min and every 10 min during the next 150 min. Blood pressure (BP) was determined every 15 min during the first 30 min and every 30 min thereafter. Area under the curve (AUC) analysis was computed for VO₂, whereas a 3-hour average and hourly averages were calculated for respiratory quotient (RQ), total kcal, HR, BP, and profile of mood states (POMS).

Results

AUC analysis revealed a 10.8% difference (p = 0.03) in VO₂ between SUP and P. No difference in VO₂ was seen between the groups in the first hour, but VO₂ in SUP was significantly greater than P in the second (13.9%, p = 0.01) and third hours (11.9%, p = 0.03). A difference (p = 0.03) in energy expenditure was seen between SUP (1.09 ± 0.10 kcal·min^-1) and P (0.99 ± 0.09 kcal·min^-1) for the 3-hour period. Although no difference in energy expenditure was seen in the first hour, significant differences between SUP and P were observed in the second (1.10 ± 0.11 kcal·min^-1 and 0.99 ± 0.09 kcal·min^-1, respectively; p = 0.02) and third hour (1.08 ± 0.11 kcal·min^-1 and 0.99 ± 0.09 kcal·min^-1, respectively; p = 0.05). Average systolic BP was significantly higher (p = 0.007) for SUP (110.0 ± 3.9 mmHg) compared to P (107.3 ± 4.4 mmHg). No differences were seen in HR, diastolic BP, or POMS at any time point.

Conclusions

Results showed a significant increase in energy expenditure in young, healthy women following an acute ingestion of a high-energy drink.