Now that she and her family are quarantining, celebrity nutritionist and mbg class instructor Kelly LeVeque has changed her shopping habits. Instead of going to the market every three days, she's filling up a cart about once a week and packing her freezer full. As for the fruits and veggies that go from the market into her fridge, she's taking one key factor into account as she's planning her meals: respiration rate. 

"I'm eating my fresh food based on respiration rate," she tells mbg. "Broccoli, leafy greens, and asparagus all break down faster, so they go into meals first. Then I think about things like cabbage, Brussels sprouts. And then it's roots, like sweet potatoes, cabbage, or anything that's like a squash. The produce that has skin or is thicker or more fibrous is going to last longer." 

Plants start to lose nutrients from the moment they're picked as a result of a natural process called respiration. This is the process in which a plant converts glucose into carbon dioxide and water using energy. Once the glucose is gone, the plant starts to wilt. "During respiration, plants break down and use their own stored nutrients to sustain themselves, which translates into fewer nutrients for you and me," explains Kelly in her book Body Love Every Day. All fruits and vegetables do this at different speeds, so when storing produce, the goal is to reduce the respiration rate in order to preserve the shelf-life of fruits and vegetables. "The more distance and time your produce has to travel to get to you, the more nutrients it must use to stay alive. Further, shipping and transit can expose your produce to variations in temperature and rough handling that speed up the cellular respiration rate," explains Kelly.

A guide from FamilyFarmed.org and the Minnesota Institute for Sustainable Agriculture is below, but if you don't know the respiration rate of your produce, think logically. "Always eat the produce that doesn't have skin first—broccoli before squash, spinach before orange," says Kelly. And just observe what's going on in your fridge: "Watch how fast produce goes bad, you know, the ones that don't last as long—asparagus will go bad before carrots," reminds Kelly. 

Very Low: Dates, dried fruits and vegetables, nuts

Low: Apple, beet, celery, cranberry, garlic, grapes, honeydew melon, onion, papaya, potato, sweet potato, watermelon

Moderate: Apricot, banana, blueberry, cabbage, cantaloupe, carrot, celeriac, cherry, cucumber, fig (fresh), gooseberry, lettuce (head), nectarine, olive, peach, pear, pepper, plum, potato (immature), radish (with tops), summer squash, tomato

High: Blackberry, carrot (with tops), cauliflower, leeks, lettuce (leaf), lima beans, radish (with tops), raspberry, strawberry

Very High: Artichoke, bean sprouts, broccoli, Brussels sprouts, endive, green onions, kale, okra, snap bean, watercress

Extremely High: Asparagus, mushroom, parsley, peas, spinach, sweet corn

There's no one right way to meal plan, but if you have a fridge full of food, taking respiration rate into account may be a good way to ensure you'll get the most from what you bought—before it goes bad.