Oils, such as extra virgin olive oil and soybean oil, help our body absorb the nutrients in greens and salads.
As a rule, the more oil you put on your salads and greens, the greater the absorption of the nutrients—up to a point. The optimal amount seems to be around 32 grams of oil, which is two tablespoons, say researchers from the Iowa State University.
The oils unlock eight micronutrients in greens and vegetables, but the body doesn't seem able to process them properly when the oil isn't added, the researchers have discovered.
The micronutrients include four carotenoids—alpha and beta carotene, lutein and lycopene—two forms of vitamin E and vitamin K. They help prevent cancer and improve eyesight among many health benefits, the researchers say.
They checked the blood of 12 volunteers after they ate greens, first without any dressing, and then with soybean oil added first. Soybean oil is common in prepared dressings bought in stores.
The nutrient levels were far higher after eating greens with the oil, the researchers discovered.