Animal evidence indicates that green tea may modulate insulin sensitivity, with epigallocatechin-3-gallate (EGCG) proposed as a likely healthpromoting component. The purpose of this study was to investigate the effect of dietary supplementation with EGCG on insulin resistance and associated metabolic risk factors in man. Overweight or obese male subjects, aged 40-65 years, were randomly assigned to take 400 mg capsules of EGCG (n 46) or the placebo lactose (n 42), twice daily for 8 weeks. Oral glucose tolerance testing and measurement of metabolic risk factors (BMI, waist circumference, percentage body fat, blood pressure, total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG) was conducted pre-and post-intervention. Mood was evaluated weekly using the University of Wales Institute of Science and Technology mood adjective checklist. EGCG treatment had no effect on insulin sensitivity, insulin secretion or glucose tolerance but did reduce diastolic blood pressure (mean change: placebo 20·058 (SE 0·75) mmHg; EGCG 22·68 (SE 0·72) mmHg; P¼0·014). No significant change in the other metabolic risk factors was observed. The EGCG group also reported feeling in a more positive mood than the placebo group across the intervention period (mean score for hedonic tone: EGCG, 29·11 (SE 0·44); placebo, 27·84 (SE 0·46); P¼0·048). In conclusion, regular intake of EGCG had no effect on insulin resistance but did result in a modest reduction in diastolic blood pressure. This antihypertensive effect may contribute to some of the cardiovascular benefits associated with habitual green tea consumption. EGCG treatment also had a positive effect on mood. Further studies are needed to confirm the findings and investigate their mechanistic basis.

Adverse skin reactions cover many types of response: toxic, irritant, allergic, urticarial, sensory, etc. The relationships between an individual's tendency to develop different types of skin response are not well-described. We examined whether those who perceive stinging might be more likely to experience urticarial, sensory and irritation reactions in skin. A panel of 86 volunteers was tested with 10% lactic acid in the nasolabial fold to assess their ability to perceive stinging. At the same time, their capacity to develop non-immunologic contact urticaria was evaluated using chemicals of different structural type and urticant ability: methyl nicotinate, benzoic acid, cinnamic acid, cinnamaldehyde and dimethyl sulfoxide (DMSO). DMSO was also used to assess sensory effects and skin irritation. 44 were classes as "stingers" and 42 as "non-stingers". The pattern of urticant reactivity in the stingers and non-stingers was essentially the same, with neat DMSO generating the strongest reactions in both groups. Sensory reactions to DMSO (stinging, itching, tingling or burning) were similar in stingers and non-stingers; although the former may have reacted more quickly, a smaller proportion reacted (64% versus 76%). The skin irritation response to DMSO was also identical in stingers and non-stingers and the intensity of the urticant response in an individual did not correlate with the intensity of their subsequent irritant reaction. In conclusion, this study demonstrated that an individual's ability to perceive skin stinging does not give a general indication of their susceptibility to other types of non-immunologic skin response. Indeed, there appeared to be little evidence of correlations between any of the skin effects studied.

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