Here's another reason to add some fresh strawberries to your yogurt, parsley to your green smoothies, and pistachios to your trail mix: New research in the journal BMJ finds that flavonoid antioxidants—present in these foods, along with many other fruits, veggies, herbs, tea, and nuts—may prevent weight gain over time. 

Harvard researchers asked more than 120,000 people what foods they regularly ate to determine their daily flavonoid intake. Then, they compared the flavonoid data to participants' changes in weight over the next 4 years. (Snack AND lose weight with this box of Prevention-approved treats from Bestowed.)

What researchers found: Every daily 194-mg dose of flavonoid antioxidants (the amount in ¾ cup of blueberries) was associated with gaining 0.2 pounds fewer over the 4 years. True, that number doesn't sound very high, but the study authors stress that even shedding a modest number of pounds—or simply staving off weight gain—can dramatically improve health. 

Why the antioxidants seem to have this effect is still a mystery, says lead author Monica Bertoia, PhD, a research associate at the Harvard School of Public Health department of nutrition. Some small animal and human studies have suggested that flavonoids might increase our resting metabolism, she explains, but many findings are still contradictory.

MORE: 10 Slimming Weight Loss Smoothies

While we wait for more research, there's no reason not to dig in: Loads of foods can provide you with that 194-mg dose of flavonoids and then some—plus tons of fiber and a litany of essential vitamins and minerals. Here are just a few ways to hit that quota:

• 1½ cups shredded red cabbage
• 1¾ cups chopped parsley
• 2 small plums
• 1 cup sliced strawberries
• ⅓ cup pecan halves
• ¾ cup pistachios
• 1 large red delicious apple
• 1½ cups blackberries