Miso & Other Fermented Soy Linked With Longevity In New Research
Soy? Longevity? That headline may be surprising if you're privy to all the conflicting information about soy that's out there.
But we're talking fermented soy products, which seem to offer more benefit than their non-fermented counterparts. Fermented soy products like tempeh, for example, may be easier to digest with their gut-healing and nutrient absorbing abilities, and according to new research, they may be linked with a lower risk of death, too.
Just look at Japan, which has become known for its residents' longevity; they're always stocked up on miso, natto, tamari, and more. So, we dug into the research to find out what makes fermented soy so special.
What the research showed.
A team of Japanese researchers studied over 90,000 men and women between the ages of 45 and 74, who were participating in an existing Japanese health study. They were looking for connections between different types of soy products and death by any cause.
The participants answered questions about their diets and lifestyles, as well as their overall health, and after 15 years, the researchers used death certificates and residential registries to find out who had died since the original research 15 years prior.
Those deaths revealed that eating more fermented soy products was associated with a 10% lower chance of all-cause death, as well as a lower risk of dying from cardiovascular disease.
Fermentation boosts health benefits.
Researchers note that as an observational study, causation between eating fermented foods and longevity cannot be guaranteed. But we do know fermented soy products are loaded with protein, fiber, and good bacteria (more so than regular soy products).
"In this large prospective study conducted in Japan with a high rate of soy consumption," the authors note, "no significant association was found between intake of total soy products and all cause mortality. In contrast, a higher intake of fermented soy products was associated with a lower risk of mortality."
And given fermented foods' gut-healing power, it's worth noting that a healthy gut has continuously been tied to longevity, too.
What comes next.
The authors say more research is necessary to figure out if soy, particularly fermented soy, has specific health effects. But for now, there's definitely enough research to support the power of fermentation in your diet.
Future studies will be conducted, according to the research team, "to refine our understanding of the health effects of fermented soy," which they hope will "inform the development of healthier and more palatable products" and "be collaborative, including not only researchers but also policymakers and the food industry."
To dive into DIY fermenting, find out how with our guide, along with what happened to this guy when he ate nothing but fermented foods for a year. And for more longevity tips, be sure to check out this doctor's guide to longevity.
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