So you work out, eat healthy, and still don’t seem to be losing weight. Maybe it’s time to look at the healthy foods you’re consuming and see if they might be the problem themselves. Recent research found that eating genetically modified foods can bypass your body’s “I’m full” trigger, leading you to eat more. Now data published in the Environmental Health Perspectives shows that a common pesticide could be causing weight gain. Called triflumizole, the chemical can contribute to packing on the pounds even when it is below the levels categorized as safe by the EPA. To avoid it? Eat only foods grown from non-genetically modified seed, and buy organic produce.

Don’t have the budget for all-organic fare? Environmental Working Group (EWG) recommends buying these 14 “Dirty Dozen +” organic all the time because of their high pesticide levels.

• Apples
• Celery
• Sweet Bell Peppers
• Peaches
• Strawberries
• Nectarines (imported)
• Grapes
• Spinach
• Lettuce
• Cucumbers
• Blueberries (domestic)
• Potatoes
• Green Beans
• Kale

Then see if it makes a difference on your waistline!