Fresh fruits and veggies aren't always healthier than frozen ones — here's why

Pip & Nut

If you need a reason to skip that trip to the farmer's market, this might be it.

A new study has debunked a commonly-held belief that the fresh, colorful fruits and veggies in the produce section are better for you than their frozen (often much cheaper) counterparts.

The paper, published last month in the Journal of Food Composition and Analysis, finds that frozen fruits and vegetables are, in many cases, more nutritious because fresh produce loses vitamins when left sitting in the fridge, even after just a few days.

For their study, the paper's authors tried to replicate how most people buy, store, and eat their fruits and veggies. Over two years, they measured the nutritional content of three types of produce: fresh, frozen, and "fresh-stored" (purchased fresh and stored in the refrigerator for five days). The items they examined were broccoli, cauliflower, corn, green beans, peas, spinach, blueberries, and strawberries.

The researchers compared the concentrations of three key nutrients in the fruits and vegetables: vitamin C, vitamin A, and folate. These nutrients are water-soluble and sensitive to heat, so they made good candidates to study when comparing frozen, fresh, and refrigerated foods.

Surprisingly, frozen fruits and veggies consistently outperformed "fresh-stored" ones in tests of these nutrients.

"The findings of this study do not support the common belief of consumers that fresh food has significantly greater nutritional value than its frozen counterpart," the authors write.

While fresh produce typically contains the highest amounts of nutrients at harvest, these nutrients start to degrade as soon as the foods are picked, packed, and assembled on produce displays. By the time we get them home and retrieve them from our refrigerators, many of these nutrients have fallen to levels lower than those seen in frozen produce, which are chilled almost as soon as they're picked from the fields.

ShutterstockWhen it comes to vitamin C, for example, fresh vegetables typically contain higher amounts than frozen or canned veggies, a study in the journal Food Chemistry found. But nutrients break down fast — a study in the journal Proceedings of the American Society of Horticultural Science found that green peas lost 52% of their wet weight in the first 24-48 hours after picking.

Another analysis, done roughly a decade ago by food scientists at the University of California Davis, came to a similar conclusion as the latest paper. "Depending on the commodity, freezing ... may preserve nutrient value," the authors wrote, adding, "exclusive recommendations of fresh produce ignore the nutrient benefits of ... frozen products."

One takeaway here is that buying fruits and veggies and eating them immediately is probably your best bet, since the nutrients inside won't have had too much time to degrade since harvesting. In most cases, however, the nutritional content of fresh and frozen produce is so similar that it won't make a meaningful difference for your health to prioritize one or the other. And in some cases — especially when we store food in the fridge for a while — frozen produce wins altogether.

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