Bacterial metabolites of diet-derived lignans and isoflavones inversely associate with asthma and wheezing

Abstract

Lignans and isoflavones are plant-derived chemicals with potent anti-inflammatory and antioxidant effects.1 Lignans are ubiquitous in Western diets, with flaxseeds containing the greatest amounts, while isoflavones are most abundant in soybeans (see Table E1 in this article's Online Repository at www.jacionline.org). The end product(s) of gut microbial metabolism of lignans is enterolactone2; metabolism of the isoflavone daidzein gives rise to equol and O-desmethylangolensin (O-DMA). Human studies demonstrate inverse associations between lignans and isoflavones and hormone-dependent cancers, cardiovascular disease, and osteoporosis,1 and improvements in asthma control are reported in those with high soy consumption.