Low-fat salad dressings are made with soybean oil or butter bases. They don’t taste half bad, but they aren’t very helpful with nutrient absorption. The polyunsaturated fats in the bases interfere with the body’s ability to absorb nutrients from fruits and vegetable in salads.
Conversely, regular salad dressings are made with either canola or olive oil. These oils contain good fats that aid the body in nutrient absorption.