Sipping on a steaming bowl of miso soup could help to ward off death, a new study has revealed.

Two types of fermented soybeans (miso, a common broth base, and natto, a more solid fermented bean) have been linked to a significantly lower risk – up to 10 per cent – of all-cause mortality among those who regularly partake in the traditional Japanese food.

However, tofu – straight-up soybean curd – did not appear to hold the same properties, according to a Japanese study published by the British Medical Journal this week.

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The team behind the study stressed it’s still very early days in finding a determinate health benefit link to consumption of overarching soy products, but the findings strengthen previously established positives for fermented products.

To try and find any links whatsoever between soy products and a lowered risk of death, the Japanese research team looked at a study of 42,750 men and 50,165 women aged between 45 and 74.

These 90,000-odd participants had to answer questions about their dietary habits, lifestyle and heath status. They were followed for almost 15 years.

What they found was the men and women who ate natto had a lowered risk of dying from cardiovascular conditions than those who pushed their plates away. This was bolstered even more if the natto fans ate a lot of vegetables.

Researchers did not, however, find any association between general soy intake (tofu, soy milk) and cancer-related death, either good or bad.

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The authors did note that natto and miso, both fermented soy products, are  richer in fibre, potassium and bioactive goodies, which might go a long way to explaining away their health benefits.

“In this large prospective study conducted in Japan with a high rate of soy consumption, no significant association was found between intake of total soy products and all cause mortality. In contrast, a higher intake of fermented soy products (natto and miso) was associated with a lower risk of mortality,” the authors wrote in conclusion.

So, basically: it still looks like fermented products hold a wee bit more of a health boost than their non-fermented counterparts, but don’t rely on them to absolve you of all other health sins.