Warren Buffett (left), Howard G. Buffett (center) and grandson Howard W. Buffett collaborated on a book about the challenges of feeding more than 2 billion more mouths by 2050. Scott Eells/Bloomberg/Bloomberg via Getty Images hide caption

itoggle caption Scott Eells/Bloomberg/Bloomberg via Getty Images

Experts say lots of factors determine how quickly an oil deteriorates — from the variety of the olives, to how the oil is produced and stored. Matthias Schrader/AP hide caption

itoggle caption Matthias Schrader/AP

Johanna Terron, 14, has lost over 20 pounds over the past year. She receives a prescription for fruits and vegetables from her pediatrician at Lincoln Hospital. Allison Aubrey/NPR hide caption

itoggle caption Allison Aubrey/NPR

At left: Beyond Eggs' egg-substitute product, a powder made of pulverized plant-based compounds. Right: Mother Nature's version. Cody Pickens/Beyond Eggs hide caption

itoggle caption Cody Pickens/Beyond Eggs

An Illinois corn and soybean farmer walks to his tractor while cultivating his field. Seth Perlman/AP hide caption

itoggle caption Seth Perlman/AP

Three women in coffee leading the way: Stephanie Backus of Portland Roasting, coffee farmer Miguelina Villatoro of Guatemala, and coffee exporter/processor Loyreth Sosa. Here they discuss coffee prices as they survey beans ready for milling. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

From left: 8-year-old Celedonia, 3-year-old Gavin, Amy Spencer and Doug Brown gather around the kitchen as Doug prepares a fruit salad for dinner. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

Regular consumption of blueberries, such as these found at Butler's Orchard in Maryland, may prevent heart attacks in middle-aged women. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

An analysis of many studies finds a small spare tire may be associated with longer life. But skeptics say that conclusion is rubbish. iStockphoto.com hide caption

itoggle caption iStockphoto.com