Bacterial Metabolism of Dietary Soy May Lower Risk Factor for Dementia

A study from researchers at the University of Pittsburgh Graduate School of Public Health published in Alzheimer's & Dementia: Translational Research & Clinical Interventions found that equol — a metabolite of dietary soy created by certain types of gut bacteria — may reduce a risk factor for dementia. ScienceDaily reports that older Japanese men and women who produce the metabolite exhibit lower levels of white matter lesions in the brain. "White matter lesions are significant risk factors for cognitive decline, dementia, and all-cause mortality," said Pitt Public Health Professor Akira Sekikawa. "We found 50 percent more white matter lesions in people who cannot produce equol compared to people who can produce it, which is a surprisingly huge effect." Although equol production did not apparently affect levels of amyloid-beta deposited within the brain, it was connected to lower white matter lesion volumes. Moreover, the researchers observed that high levels of isoflavones — soy nutrients metabolized into equol — did not impact white matter lesions or amyloid-beta when equol was not produced. Although Sekikawa hopes to assess the neuroprotective effects of equol supplements, for now he recommends caution for anyone who might think they will guard against dementia. "We cannot prove that equol protects against dementia until we get a randomized clinical trial with sufficient evidence," he explained.