Perhaps the best thing you can do to extend your life is to start your day with a smoothie made from colorful, fresh ingredients like apples, berries, and yes, a little bit of kale.

All of these foods contain heaps of flavonoids, which new research finds protect against cancer and heart disease, two of modern society's biggest killers. 

If you don't consider yourself the kind of health fanatic who would start your day with a smoothie or you have some bad habits like heavy smoking and drinking, it turns out upping your daily dose of flavonoids can be even more beneficial. 

Researchers from Australia's Edith Cowan University used data from Denmark that tracked the diets of over 53,000 Danes for 23 years and found people who habitually consumed moderate to high levels of flavonoids were less likely to die from cancer or heart disease. This "protective effect" was most pronounced for those at the highest risk of the maladies because of smoking cigarettes or drinking more than two alcoholic drinks daily. 

"These findings are important as they highlight the potential to prevent cancer and heart disease by encouraging the consumption of flavonoid-rich foods, particularly in people at high risk of these chronic diseases," said lead researcher Dr. Nicola Bondonno.

"But it's also important to note that flavonoid consumption does not counteract all of the increased risk of death caused by smoking and high alcohol consumption," she added. "By far the best thing to do for your health is to quit smoking and cut down on alcohol."

The study was published Tuesday in Nature Communications.

Researchers say that flavonoid-rich foods like apples, drinks like tea, and moderation could be the ideal three-pronged approach to living longer.

"Encouraging flavonoid consumption might be a novel way to alleviate the increased risk, while also encouraging people to quit smoking and reduce their alcohol intake," said Bondonno.

So what is the specific recipe for getting a flavonoid-powered longevity boost? The data shows that about 500 mg of total flavonoids each day may be the sweet spot. 

"It's important to consume a variety of different flavonoid compounds found in different plant-based food and drink," Bondonno explained. "This is easily achievable through the diet: one cup of tea, one apple, one orange, 100 g of blueberries, and 100 g of broccoli would provide a wide range of flavonoid compounds and over 500 mg of total flavonoids."

For a more detailed menu of the different types of flavonoids and the foods that contain them, check out this handy chart from Oregon State University.

A tall smoothie made from some berries, citrus, kale, celery, and a bit of peanut butter alongside a glass of tea could be enough to cover your flavonoids bases for the day. As an added bonus, red wine and cocoa-based chocolate also count. 

What exactly it is about flavonoids that seems to stave off cancer and heart disease isn't fully clear, but Bondonno has some thoughts.

"Alcohol consumption and smoking both increase inflammation and damage blood vessels, which can increase the risk of a range of diseases," she said. "Flavonoids have been shown to be anti-inflammatory and improve blood vessel function, which may explain why they are associated with a lower risk of death from heart disease and cancer."

Whatever the reason, it's science worth raising a glass to, especially if it's a smoothie packed with flavonoids.