Abstract-Intake of flavonoids is associated with a reduced cardiovascular risk. Oxidation of LDL is a major step in atherogenesis, and antioxidants may protect LDL from oxidation. Because tea is an important source of flavonoids, which are strong antioxidants, we have assessed in a randomized, placebo-controlled study the effect of consumption of black and green tea and of intake of isolated green tea polyphenols on LDL oxidation ex vivo and on plasma levels of antioxidants and lipids. Healthy male and female smokers (aged 34Ϯ12 years, 13 to 16 per group) consumed during a 4-week period 6 cups (900 mL) of black or green tea or water per day, or they received as a supplement 3.6 grams of green tea polyphenols per day (equivalent to the consumption of 18 cups of green tea per day). Consumption of black or green tea had no effect on plasma cholesterol and triglycerides, HDL and LDL cholesterol, plasma vitamins C and E, ␤-carotene, and uric acid. No differences were found in parameters of LDL oxidation. Intake of green tea polyphenols decreased plasma vitamin E significantly in that group compared with the control group (Ϫ11% Pϭ.016) but had no effect on LDL oxidation ex vivo. We conclude that consumption of black or green tea (6 cups per day) has no effect on plasma lipids and no sparing effect on plasma antioxidant vitamins and that intake of a high dose of isolated green tea polyphenols decreases plasma vitamin E. Although tea polyphenols had a potent antioxidant activity on LDL oxidation in vitro, no effect was found on LDL oxidation ex vivo after consumption of green or black tea or intake of a green tea polyphenol isolate. (Arterioscler Thromb Vasc Biol. 1998;18:833-841.)

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Elevated TSH secretion in obese women is significantly reduced by diet-induced weight loss. Among various physiological cues, leptin may be involved in this phenomenon. The decreases in TSH and free T3 may blunt energy expenditure in response to long-term calorie restriction, thereby frustrating weight loss attempts of obese individuals.

Among women with hirsutism, an adrenal tumor is unlikely if the patient has normal basal serum concentrations of testosterone and dehydroepiandrosterone sulfate. In women in whom these concentrations are elevated, a tumor is unlikely if the serum concentration of dehydroepiandrosterone sulfate and urinary 17-ketosteroid excretion are in the normal basal range and the serum cortisol concentration is less than 3.3 micrograms per deciliter after the administration of dexamethasone.