About half of people say they’re actively trying to eat more healthfully — and that's great. But if that's the case, why are fully 70% of adults still overweight or obese?

The answer may be in people’s snacking habits.

Snacks account for at least 25% of most adults’ daily calories, and 90% admit to eating one to three snacks a day. Unfortunately, those between-meal bites are usually not a handful of walnuts, a bunch of grapes, or an apple. They're highly processed, sugar-loaded, saturated-fat-soaked treats that overwhelm the benefits from healthier meals.

That's the finding of a new study in the European Journal of Nutrition. Looking at the eating habits of more than 800 people, the researchers found that the most popular and calorie-packed snacks are cookies, cheese, cakes, ice cream and frozen dairy desserts, pies, granola, and cereal bars. These snacks are associated with being overweight, and having more belly fat and higher triglyceride levels.

What’s particularly unhealthy? Eating snacks after 9 p.m. — when choices tend to be the highest in fats and sugar.

This doesn't mean you have to give up snacks. People who eat healthy snacks such as nuts, fruits, and vegetables were found to have a healthier weight than unhealthy snackers and those who didn't snack at all.

In fact, a well-timed healthy snack can help keep your metabolism humming and glucose levels steady.

Next time you reach for a midday nosh, make it a healthy choice. You'll live younger longer. And for great snack ideas, check out LongevityPlaybook.com.