Guest post by Caroline Markowitz – MS candidate in nutrition and exercise physiology at Columbia University

Grocery stores and farmers markets display signs touting “organic” and “local” above their produce. But so many of us feel fraught with confusion. Is eating organic always better? What if something is local but not organic, what should I choose? What does it all mean? The questions feel never ending. In a recent NYTimes “Climate Fwd” newsletter, Eduardo Garcia and Lisa Friedman explain that organic farming can have an equal (if not greater) carbon footprint than conventional farming; however, organic farming is likely better for the planet overall because it does not use synthetic herbicides and pesticides that conventional farming relies on.

Conventional agriculture: “a broad term that has a number of definitions, but a crop can be classified as conventional if synthetic chemicals are used to maintain the plants. A significant amount of chemical and energy input is required in conventional agriculture to produce the highest possible yield of crops.”

Organic agriculture: “Organic farmers, ranchers, and food processors use agricultural methods intended to preserve the environment. USDA organic regulations restrict the use of certain conventional tools such as synthetic fertilizers and pesticides.”

Local farming: “Local farming means short distribution channels – channels involving no more than one intermediary between farm and consumer. Local farming is aimed at, among other things, reducing the distances travelled by fruits and at reestablishing the relationship between consumer and farmer.”

Purchasing local produce from small farms, even if they aren’t certified organic, is likely the most sustainable route. These farmers tend to have a lower carbon footprint because their practice “often involves growing a wider variety of crops, and smaller farmers don’t typically package their products in single-use plastics or transport them to buyers hundreds of miles away (Friedman and Garcia, Know Your Organic Food).” It is also important to take into consideration that obtaining a USDA Organic Certification is expensive; many small farmers utilize organic practices, but are unable to pay for the certificate.

In their book Fearless Feeding: How to Raise Healthy Eaters from High Chair to High School, authors Jill Castle and Maryann Jacobsen explain which foods, from a health perspective, are best to buy organic and those to buy conventional. Their recommendations for purchasing organic are based on the higher level of pesticides typically used on these foods when farmed conventionally.

2012 review found no major differences in nutritional attributes and health-related outcomes from organic or conventional food, but did find decreased pesticide residues in urine of kids with organic diet. Children are at the greatest risk of pesticide exposure because their brain is still developing and they ingest more (but any produce is better than none)

Best to buy conventional: onions, sweet corn, pineapple, avocado, asparagus, sweet peas, mango, eggplant, cantaloupe (domestic), kiwi, cabbage, watermelon, sweet potato, mushrooms, grapefruit

Best to buy organic: apples, celery, strawberries, peaches, spinach, nectarines (imported), grapes, sweet bell peppers, potatoes, blueberries (domestic), lettuce, kale, green beans, cucumber

Castle & Jacobsen, Fearless Feeding: How to Raise Healthy Eaters from High Chair to High School.