Healthy eating costs you $1.50 more a day, study says

(CNN) - $1.50 a day -- That's how much more it costs to eat a healthier diet, according to a study by Harvard researchers.

They say the price difference is less than they expected.

The researchers reviewed 27 studies conducted after the year 2000 on the cost of healthy verses unhealthy versions of certain foods -- for example, lean beef versus a fattier cut.

The studies also included comparisons of healthy and unhealthy diet patterns, such as a diet rich in fruits and vegetables versus a diet without fresh produce.

The studies came from 10 countries, including the U.S., Canada and several European nations.

The food prices were converted to international dollars and adjusted for inflation.