
tim290280
Mecca V.I.P.
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I was interested in this supposed multi-million dollar research budget and what it actually gets spent on. So being bored and hungover I decided to do a quick search on Google scholar. Below are the studies that I have found. The rest were usually patent applications for the individual ingredients; all of which make for surprisingly boring reading (who the hell patents the creatine dosage they put in a supplement??)
This one is they gave a couple of travel grants to, not anything else as far as I can see.Concentrations of Ephedra Alkaloids and Caffeine in Commercial Dietary Supplements
Authors: Haller C.A.1; Duan M.1; Benowitz N.L.1; Jacob III P.1
Source: Journal of Analytical Toxicology, Volume 28, Number 3, April 2004 , pp. 145-151(7)
Abstract:
Dietary supplements that contain Ma Huang (ephedra alkaloids) and guarana (caffeine) are widely marketed and used in the U.S. for weight loss and athletic performance enhancement, despite a lack of adequate research on the pharmacology of these botanical stimulants. We developed and applied a novel liquid chromatography–tandem mass spectrometry (LC–MS–MS) method to quantitate the various ephedra alkaloids found in dietary supplements that contain Ephedra species. The quantities of ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedine, methylpseudoephedrine, and caffeine were determined for 35 commercial dietary supplements and compared with the amounts listed on the product labels. The total ephedra alkaloid content ranged from 5.97 mg to 29.3 mg per serving. Two supplement brands did not list the quantity of ephedra alkaloids on the label, and four did not list the amount of caffeine per serving. Of the products tested, 31% contained > 110% of the total ephedra alkaloids listed on the label, and 6% of the supplements contained < 90% of the listed amount. For caffeine, 86% of the product lots that listed the caffeine amount contained less than 90% of the labeled quantity. No products contained > 110% of the declared caffeine content. The total ephedra alkaloid content varied significantly from lot to lot in 5 of 9 products. Three product brands contained proportions of alkaloids that exceeded amounts reported for E. sinica, including one that was 98% ephedrine, one that had 10% norpseudoephedrine, and one that contained an average of 13% methylephedrine. We conclude that product inconsistency is common among some commercially available dietary supplements that contain ephedra alkaloids and caffeine.
Simple skinfold-thickness measurements complement conventional anthropometric assessments in predicting glucose tolerance1,2,3
John L Sievenpiper, David JA Jenkins, Robert G Josse, Lawrence A Leiter and Vladimir Vuksan
1 From the Department of Nutritional Sciences, Faculty of Medicine, University of Toronto and the Clinical Nutrition and Risk Factor Modification Centre, and the Division of Metabolism and Endocrinology, St Michael's Hospital, Toronto.
Background: Skinfold-thickness measurements are considered to have limited clinical utility.
Objective: To assess whether skinfold-thickness measurements may be a useful adjunct to conventional anthropometric assessments in predicting glucose and insulin regulation, we studied responses to replicate 75-g oral-glucose-tolerance tests (OGTTs) and performed simple anthropometry in a cross section of subjects.
Design: Thirty-five subjects completed the study: 11 lean [mean (±SEM) age: 33 ± 3.2 y; body mass index (BMI; in kg/m2): 24.1 ± 0.8; and percentage body fat (%BF): 11.5 ± 1.5%], 12 normal-weight (age: 33 ± 2.9 y; BMI: 23.9 ± 0.7; and %BF: 24.3.5 ± 1.3%), and 12 obese (age: 41 ± 4.5 y; BMI: 34.5 ± 1.7; and %BF: 34.2 ± 1.5%) individuals. The lean and normal-weight groups were selected to have similar BMIs but different %BFs. We measured the participants' heights, weights, %BFs, waist circumferences, hip circumferences, and truncal and peripheral skinfold thicknesses. Subjects received nine 75-g OGTTs and blood samples were collected at 0, 15, 30, 45, 60, 90, and 120 min. Mean plasma glucose and insulin values were used to calculate the insulin sensitivity index.
Results: The obese group had higher plasma glucose concentrations and areas under the curve (AUCs) than did the normal-weight or lean group and higher plasma insulin concentrations and AUCs than did the lean group (P < 0.05). Stepwise multiple regression, with adjustment for demographic and anthropometric measurements, identified the following predictors: waist circumference, peripheral skinfold thickness, and BMI for fasting plasma glucose (partial R2 = 0.20, 0.13, and 0.13, P < 0.05); waist circumference and truncal skinfold thickness for plasma glucose AUC (partial R2 = 0.20 and 0.13, P < 0.05); age, waist-to-hip ratio, and peripheral skinfold thickness for fasting plasma insulin (partial R2 = 0.26, 0.22, and 0.15, P < 0.05); truncal skinfold thickness for plasma insulin AUC (partial R2 = 0.41, P < 0.001); and peripheral skinfold thickness for both 2-h plasma glucose (partial R2 = 0.59, P < 0.001) and the insulin sensitivity index (partial R2 = 0.49, P < 0.001).
Conclusion: Skinfold-thickness measurements may complement other established measurements for predicting abnormal glucose and insulin regulation.
Key Words: Glycemia • insulinemia • oral-glucose-tolerance test • anthropometry • body composition • skinfold thickness