Lighting Improves Nutrient Content in Spinach

Supermarket lighting not only keeps your spinach fresh but it can also help produce new vitamins, according to U.S. Government researchers. These surprise findings may apply to other fresh produce and may offer insights on how we can keep our produce fresher for longer periods of time.

Reporting in the Journal of Agricultural and Food Chemistry, the researchers kept spinach under continuous light or darkness for three to nine days.

The spinach that was exposed to light for as little as three days had significantly higher amounts of vitamins C, K, E, and folate, in addition to healthy antioxidants such as lutein and zeaxanthin, both considered excellent for eye health. The spinach stored in the dark lost nutrients.

"These vitamins are basically in the plant for photosynthesis and we humans, being the biggest predator of plants, have evolved over time to utilize them as opposed to we having to manufacture them," said Gene Lester of the U.S. Department of Agriculture's Agricultural Research Service.

Even after the spinach is picked, the leafy greens continue to photosynthesize as long as there is moisture, gas exchange and light.

His team decided to use fresh spinach as it is "arguably one of the most nutritionally complete vegetables commonly consumed." A serving of spinach provides 20 percent or more of the recommended dietary intake of vitamins C, A, B9, K and E.

As we often store our produce in a dark refrigerator, we can apply this research and greatly improve the nutrient content of the foods we eat simply by exposing them to light. Place your fruits and veggies in front of a window or areas of high light and you'll be able to reap the benefits of more healthful, nutrient-dense food.