A number of studies have explored the phenomenon of declining nutrients in fruits and vegetables, but the one that garnered the most media attention was led by Donald R. Davis, PhD, at the University of Texas in Austin, and was published in HortScience. Among Davis’s findings, one of the most consistent was that a higher yield of crops — in other words, more crops grown in a given space — almost always resulted in lower nutrient levels in the fruits and vegetables. What’s more, the median mineral declines among a variety of fruits and vegetables could be fairly significant, ranging from 5 to 40 percent, with similar declines in vitamins and protein levels.
Higher yield is one reason behind the decline, but several nutrition experts say it's not the only one. “The soil itself has been over-harvested, meaning that over years of use and turnover of soil, it becomes depleted in nutrition,” says Michael Wald, MD, an integrated medicine specialist in Mount Kisco, N.Y. “All crops growing upon depleted soil must therefore be depleted in nutritional content.”
Cherie Calbom, MS, a clinical nutritionist and author of The Juice Lady's Living Foods Revolution, sees it as a bigger problem that extends to many aspects of modern farming. “Our poor farming practices are leading to sick plants, depleted soil, and a need to use higher and higher doses of pesticides and herbicides to ward off what healthy plants would naturally ward off,” she says. “We are heading toward a dust bowl in many parts of the country if nothing changes.”
Despite these concerns, Janet Brill, PhD, RD, a nutritionist and author of Cholesterol Down, it’s still critically important to eat lots and lots of fruits and vegetables, and these developments shouldn’t discourage you from doing just that. “People should be concerned about one area of fruits and vegetables and one area only: to eat lots more of them each day, cooked and raw,” she says. “After we have solved that problem [of consumption], then we can move on to any nutrition concerns about growing them.”
5 Ways to Get the Most Out of Your Fruits and Veggies
There are still many steps you can take to ensure a healthy nutrient punch every time you include fruits and vegetables in your diet.
Go with locally grown. The key to getting more nutrients is eating food that spends less time traveling from the field to your table. The way to accomplish that goal is with locally grown produce, either from your own garden or from a local farmer’s market. “Buy fresh, whole, and locally grown seasonal produce,” Brill suggests. “Try to purchase produce with the least amount of time from farm to table, as vitamins and minerals are lost over time as well as with cooking and handling.”
Choose frozen. Your natural instinct when eating produce is to think that fresh is always better than frozen. But Brill says that this isn’t necessarily the case. “Sometimes the veggies frozen right after harvest have retained more nutrients than those ‘fresh’ veggies that have taken forever to get to your plate,” she explains.
Don’t judge a book by its cover. Big, shiny fruits and vegetables sure look good and grab your attention in the supermarket, but just because they’re beautiful doesn’t mean they’re better for you. For example, organic apples may be smaller and not quite as pretty, but their pesticide levels are likely to be lower.
Keep them rough. When it comes time to prepare those fruits and vegetables for eating, bigger, rougher pieces of produce may have the nutritional edge over finely chopped and sliced options. “Keep chopping to a minimum,” Brill advises. “The greater the exposure of the fruit or vegetable to air, the greater the loss of nutrients.”
Minimize cooking time. Though there are some exceptions (the lycopene in tomatoes, for example), the less most fruits and vegetables are cooked, the more nutrients they retain. So eat your fruits and vegetables raw whenever possible. When you do cook them, keep the cooking time to a minimum and avoid too much contact with water. “Cooking methods that are quick, with a minimum amount of liquid, will help to preserve nutrients,” Brill says. “Steaming, blanching, and stir-frying are all great ways to cook vegetables quickly and retain valuable nutrients. Keep veggies crisp — never overcook or boil in water until soggy.”
It may take a bit more effort to find fruits and vegetables as nutrient-rich as they were 50 years ago, but with more local farm stands cropping up, seasonal choices are getting easier to find and are certainly more delicious.