Bérubé-Parent S, Pelletier C, Doré J, Tremblay A Effects of encapsulated green tea and Guarana extracts containing a mixture of epigallocatechin-3-gallate and caffeine on 24 h energy expenditure and fat oxidation in men. Br J Nutr. 2005 Sep;94(3):432-6.
Borchardt RT, Huber JA Catechol O-methyltransferase. 5. Structure-activity relationships for inhibition by flavonoids. J Med Chem. 1975 Jan;18(1):120-2.
Curatolo PW, Robertson D The health consequences of caffeine. Ann Intern Med. 1983 May;98(5 Pt 1):641-53. Review.
den Besten C, Vansant G, Weststrate JA, Deurenberg P Resting metabolic rate and diet-induced thermogenesis in abdominal and gluteal-femoral obese women before and after weight reduction. Am J Clin Nutr. 1988 May;47(5):840-7.
Diepvens K, Westerterp KR, Westerterp-Plantenga MS Obesity and thermogenesis related to the consumption of caffeine, ephedrine, capsaicin, and green tea. Am J Physiol Regul Integr Comp Physiol. 2007 Jan;292(1):R77-85. Epub 2006 Jul 13. Review.
Dulloo AG Ephedrine, xanthines and prostaglandin-inhibitors: actions and interactions in the stimulation of thermogenesis. Int J Obes Relat Metab Disord. 1993 Feb;17 Suppl 1:S35-40. Review.
Klaus S, Pültz S, Thöne-Reineke C, Wolfram S Epigallocatechin gallate attenuates diet-induced obesity in mice by decreasing energy absorption and increasing fat oxidation. Int J Obes (Lond). 2005 Jun;29(6):615-23.
Segal KR, Gutin B, Nyman AM, Pi-Sunyer FX Thermic effect of food at rest, during exercise, and after exercise in lean and obese men of similar body weight. J Clin Invest. 1985 Sep;76(3):1107-12.
Thearle M, Aronne LJ Obesity and pharmacologic therapy. Endocrinol Metab Clin North Am. 2003 Dec;32(4):1005-24. Review.
Westerterp-Plantenga MS, Lejeune MP, Kovacs EM Body weight loss and weight maintenance in relation to habitual caffeine intake and green tea supplementation. Obes Res. 2005 Jul;13(7):1195-204.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.