Wendy White, an associate professor in food science and human nutrition at Iowa State University, led a recent study that suggests eating salad greens and vegetables with added fat—in the form of soybean oil—enhances the absorption of various micronutrients that promote human health. Soybean oil is a common ingredient in commercial salad dressings.
Salad vegetables with added oil aided in the absorption of several micronutrients: alpha and beta carotene, lutein, and lycopene; two forms of vitamin E and vitamin K; and vitamin A. White said better absorption of these nutrients promotes a range of health benefits, including cancer prevention and eyesight preservation.
The study also found that the amount of oil added to the vegetables had a proportional relationship with the amount of nutrient absorption. White said, “The best way to explain it would be to say that adding twice the amount of salad dressing leads to twice the nutrient absorption.” This doesn’t mean salad eaters should drench their greens in dressing! White indicates that consumers should be comfortable with the U.S. dietary recommendation of about two tablespoons of oil per day.
The research study showed eating the same salad without the added oil lessened the likelihood that the body would absorb the nutrients.