What's the perfect ratio for our five-plus a day?

We should include at least three servings of vegetables and two servings of fruit a day.
We should include at least three servings of vegetables and two servings of fruit a day. Photo credit: Getty

We've all heard of the saying 'five-plus a day keeps the doctors away' but do we know how much of each we should be consuming?

Research published by the American Heart Association says we should include at least three servings of vegetables and two servings of fruit as part of our five-plus a day.

The intake of five servings of fruit and vegetables is associated with a lower risk of chronic health conditions including cardiovascular diseases and cancer.

Yet only one in 10 US adults eat the desired amount, according to research from the US Centers for Disease Control and Prevention (CDC).

The study included more than 1.9 million participants from 29 countries, whose dietary information was repeatedly collected every two to four years for up to 30 years.

Compared to those who consumed two servings of fruit and vegetables per day, those who consumed five a day had a 14 percent lower risk of death from all causes.

They also had a 12 percent lower risk of death from cardiovascular disease, including heart disease and stroke, 10 percent lower risk of death from cancer, and a 35 percent lower risk of death from respiratory disease.

"This amount likely offers the most benefit in terms of prevention of major chronic disease and is a relatively achievable intake for the general public," lead study author Dong D Wang said.

The study also found that not all fruits and vegetables offer the same degree of benefit.

Starchy vegetables, such as potatoes, peas, corn and fruit juice were not associated with the reduced risk of death from chronic diseases.

On the other hand, leafy greens, such as spinach, lettuce and kale, and fruit and vegetables rich in beta carotene and vitamin C, such as citrus, berries and carrots, showed benefits.

"This research provides strong evidence for the lifelong benefits of eating fruits and vegetables and suggests a goal amount to consume daily for ideal health," associate professor of medicine at Harvard Medical School Anne Thorndike said.

"Fruits and vegetables are naturally packaged sources of nutrients that can be included in most meals and snacks, and they are essential for keeping our hearts and bodies healthy."