Hippocrates, who lived in Greece 2,500 years ago, is considered the father of medicine because he used observation and deduction to understand and treat illness. His take? "All diseases begin in the gut."

Now, we know this isn't entirely true (a tick bite delivering Lyme disease is an outside invader, for example), but ever more evidence is showing how closely your gut health is linked to your well-being, in terms of weight, glucose levels, immune system, brain function and inflammation control.

Now, research published in European Heart Journal — involving more than 600 women from the TwinsUK study — has explored your gut-heart connection.

For the first time, there's confirmation that the greater the diversity in your gut bacteria, the less stiff your arteries will be, and that lowers your risk for heart attack and stroke.

How do you make sure you've got a diverse gut microbiome?

By eating a diverse diet made up of fiber-rich, polyphenol-loaded fruits, veggies, and grains, fermented foods like kimchi and sauerkraut, healthy oils like the omega-3 DHA in salmon, and maybe a variety of probiotic supplements.

Another smart choice? Twelve walnut halves daily. They'll help decrease weight gain and are associated with a lower risk of heart attacks and strokes.

They also provide a big boost to your gut's microbiome by substantially increasing four types of colon-protecting, inflammation-fighting bacteria (Faecalibacterium, Clostridium, Dialister and Roseburia).

So remember that old saying, "The way to the heart is through the stomach," and start nurturing more diversity in your gut biome.