Fresh fruits and vegetables are a dieter’s dream, but the pesticide residue on them can keep your calorie-burning machine from performing at its peak.

Pesticides may affect your thyroid’s ability to function and there’s evidence that they also harm the functioning of mitochondria, the parts of a cell that convert fuel into energy.

Government researchers say you need to scrub fresh produce for at least 30 seconds to remove the residue.

You can also minimize your exposure by purchasing organic produce, especially the kind with an edible peel, as well as organic beef and dairy products, because regular cattle feed can contain high concentrations of pesticides.