Is a diverse diet good for you? Maybe not

New research shows dietary diversity may not be good for you

We all have dietary needs to meet, and it takes a wide variety of foods to do that -- or does it?

A recent review of research on dietary diversity shows the widely accepted recommendation to eat a large variety of foods may be way off track.

“People eating a greater variety of foods had, in general, consumed more calories. And in some studies it was also linked to greater obesity," said Dr. Marcia Otto, epidemiologist at UTHealth School of Public Health. "In one of the studies, for example, they found that people with greater number of different foods consumed in a week, they had, over time, a 120 percent increase in waist circumference after five years.”

The analysis of recent studies is so convincing that the American Heart Association released a scientific statement about it.

The conclusion: there’s no consistent evidence that more diversity promotes healthy weight or optimal eating.  In fact, Otto, the lead author of the study, said it could be the opposite. 

“If one is eating one food over time, the appetite goes down, whereas when one is exposed to a large variety of different flavors, the appetite tends to remain up for a longer period of time, leading to greater food intake," Otto said.

She said there’s evidence the increase in options may delay the feeling of fullness, contributing to overeating and weight gain.

The AHA said you should instead focus on getting a few of the right foods. Think fish, poultry and nuts, fresh or minimally processed plant foods such as vegetables, beans, fruits, whole grains, and low-fat dairy products.

And know there are situations where the greater variety can be a good thing.

"For elderly populations, for example, where under-consumption of food is a concern. Then increasing variety may at the same time increase intake of foods and that may be beneficial," Otto said.

But no matter what the age, it’s important to be sure whatever you do is intentional.

“I keep one chocolate bar -- dark chocolate that I love -- and that's my snack for the day," Otto said. "I know that if I had a number of different snack options, I would be eating a lot more snacks.”