Interviewer: "I was really intrigued by a video of yours regarding miso and not increasing blood pressure. Is there a limit to the amount of miso that I can put into a dish? Obviously it gets really salty but is there a limit?"

Dr Greger: "As far as miso, the studies were done with these Japanese populations who are eating bowls of miso soup a day! That's a lot of miso. That's a lot of sodium. The two things we would worry about with excess sodium consumption is hypertension -- it's the number one risk factor for death in the world and then stomach cancer. But people that eat miso don't have higher blood pressures and don't have higher stomach cancer risk! So what we think is happening is that the protective benefits of the soy (whole soy foods) is counteracting the negative effects of the sodium! So say, it actually has a neutral beneficial effect. Now you say, "wait a second! Why not instead eat edamame or something to get all the soy benefits without the sodium negatives? Wouldn't that be even better?" Maybe. I mean it's a great way to add a salty taste to a dish without increasing disease risk.

Interviewer: "So the salt-oil-sugar free diets, you know, for a lot of people: salt is really hard to cut back on! They're really used to eating salt, including myself! If I just switch over to miso, am I fine? Is that what it means?"

Dr Greger: "That's what it means! That's how I make food salty. So you just add miso to dressings, to sauces, to anything you want!"

A systematic review of all soy and prostate cancer population studies to date confirmed soy foods "could lower the risk." But that's kind of a broad category. There's all sorts of soy foods. There's fermented soy foods, like miso and tempeh, and unfermented foods, like tofu and soy milk. Which is more protective? Researchers sifted through the studies. And, it turns out that only the unfermented soy seemed to help. Tofu and soy milk consumption were associated with about a '30% reduction in risk, whereas there didn't appear to be any protection linked to fermented soy foods.

Dr. Klaper offers nutrition advice about miso paste, fermented soy paste, and a favorite ingredient in Japanese food. Miso paste contains a fair amount of salt (sodium) and adds to your daily sodium intake. He says that the effects of eating soy help to dilate the blood vessels and do not increase blood pressure. In some cases eating miso paste can lower blood pressure. As long as it's in moderation, miso paste salt can be part of your healthy whole foods plant-based diet.