Stress can provide an antioxidant boost to fruits and vegetables
The amount of flavonoids – antioxidants found in fruits, nuts and vegetables linked to disease prevention – depends on how much stress the plant has endured, says a US government report.
In its most comprehensive study yet on the healthy compounds, the US Department of Agriculture suggests that certain varieties of fruits, nuts and veggies contain more antioxidants than others.
The research shows that the difference may be due to stress, which appears to increase the healthful properties of produce. Nutritionist David Haytowitz, one of the study’s authors, said that taxing conditions, such as those created by more natural farming methods, appeared to force plants to release greater amounts of flavonoids and other beneficial compounds.
“Insect attacks and weather conditions can be stressful to plants,” he said. “Even harvest times are important, as early morning harvests are less stressful than those conducted around noon, since the midday sun adds to a plant’s stress.”
Another positive factor was colour, which was chemically linked to many antioxidants. Raw blueberries, blackberries, cranberries and strawberries all ranked very highly for several flavonoids that have been shown to reduce inflammation and to rid the body of damaging free radicals.
Mr.Haytowitz said that “we are very interested, because they may help to prevent coronary vascular disease, cancer and other diseases”.