城市生活可能正在导致我们的雌激素水平发生重大变化

DISCARDED sex hormones can be returned to the bloodstream by bacteria in the gut – and now, a study has found that there are far more of these sex-hormone- recycling bacteria in the guts of people in industrialised societies than in those of hunter-gatherers and non-industrial farmers. This might mean that, as a result of urban living, some people have higher blood levels of certain sex hormones. Sex hormones, such as oestrogens, circulate in the blood. When levels are too high, cells in the liver add a chemical tag that results in a hormone being excreted, often via the gut. But that tag happens to be a sugar molecule that certain bacteria feed on. …