While fruits and vegetables are very nutritious and should be a core component of a healthy diet, studies have shown that some fruits and vegetables are more likely to contain pesticide residues, says Peggy O'Shea. "Research has shown that prolonged exposure to pesticide residue may increase risk of certain types of cancer, some neurological issues, such as Parkinson's disease, and perhaps even impair the immune system," she says.

O'Shea says there has been more attention around this issue in recent years, and strawberries have been identified as one of those that, on average, have higher levels of contamination from pesticides (others include cherries, apples, raspberries, peaches, peas, spinach, Mexican cantaloupe).

"There are ways to minimize the amount of pesticide residue on your fruit and vegetables, including making sure you eat a variety of foods to lessen exposure to any one pesticide, and properly and thoroughly washing your fruits and vegetables before eating," O'Shea says. "Also, I would recommend choosing organic produce, especially for strawberries (and others that have a higher propensity to have pesticide residue). Organic produce may cost a little bit more, but when it comes to certain fruits and vegetables, it can really make a difference, and reduce exposure to potentially harmful pesticides."