Cook Your Vegetables ASAP

Nitrates are a chemical found in water and soil, and they're a concern when it comes to feeding your baby. Babies who ingest an unsafe level of nitrates can develop a type of anemia called methemoglobinemia.

Preparing formula with well water that's high in nitrates is the usual cause of the illness, but some vegetables can also contain nitrates. The most likely sources are beets, carrots, green beans, spinach, and squash.

To be on the safe side, the American Academy of Pediatrics (AAP) advises parents not to feed babies these vegetables before 3 months of age. (Actually, the AAP doesn't recommend feeding babies any solid food until 4 to 6 months, but if you do decide to offer your infant vegetables before 3 months, you'll want to avoid these in particular.)

There are a few things you can do to make sure your baby isn't exposed to high levels of nitrates. If you have well water, have it tested. It should contain less than 10 ppm of nitrates.

Nitrates increase with storage time unless frozen. When using fresh vegetables for homemade baby food, prepare the food as soon as possible after purchase and freeze extra servings right away. You might consider using frozen vegetables instead of fresh for the foods highest in nitrates.

Nitrate fertilizers are not used on land where produce is grown organically, so the risk of nitrates is much lower with certified organic produce.Baby food companies test their products for nitrates. Store-bought baby food — including dishes containing beets, carrots, green beans, spinach, or squash — should be free of these chemicals.