Calorie counts are showing up on menu boards across the nation, giving consumers an easy way to make better choices.

You might be surprised, for example, to know that piece of Starbucks banana walnut bread has 490 calories. A grande iced white chocolate mocha adds another 450. The two add up to more than half the calories many of us should consume in a whole day, but people treat it as a mid-day snack.

Starbucks, along with McDonalds and others, have long made that information available on websites, but now they’re putting it front-and-center where it’s harder to ignore.

The Affordable Care Act will eventually require such disclosure, but some companies are posting before the rules take effect. Also, some regions, such as New York City and Washington state’s King County have approved their own requirements. We think such demands should come from customers, not government, but the big question now is what use consumers will make of the information.

A Starbucks patron, for example, could choose a tomato and cheese croissant for 250 calories, or a spinach and feta breakfast wrap for 290. And how about a smaller skinny mocha for 170 calories or plain coffee for 5 calories? That calorie total is far more manageable.

Research on the effectiveness of menu-board calorie postings is mixed, with some reports saying it makes no difference and others finding meaningful reactions from about a third of customers, according to a report in The Oregonian.

Obesity is a huge and growing issue, and people are eating out more than ever. Only the most conscientious consumer will study the website before ordering food at a restaurant, but there’s reason to hope many more will respond when the figures are right in front of their faces. Truth is, ordering a piece of banana bread doesn’t feel extravagant when you don’t know its calorie load. Armed with comparisons at the moment of purchase, it’s far easier to make a better choice.