Don't bother asking for your dressing on the side. A new study published in the American Journal of Clinical Nutrition shows that salads are healthier and more nutritious when they're covered in full-fat dressing, rather than reduced- or low-fat versions.
The study assessed the vegetables' bioavailability - the proportion of the nutrients that are actually absorbed by your digestive system after you eat a certain food. A food with a low bioavailability wouldn't provide your body with much nutrition, while a food with higher bioavailability gives you more bang for your buck.
The bioavailability of vegetables dressed with full-fat dressings was much higher than that of vegetables without fatty dressing. So eating those under-dressed vegetables could be less efficient for you than enjoying a fattier bed of greens.
The salad with full-fat oil-based dressing allowed for better absorption of eight different micronutrients: alpha- and beta-carotene, lutein, lycopene, two forms of vitamin E, vitamin K, and vitamin A.
"The question remains as to how much fat is needed," the results of the study read. The exact number of grams of the macronutrient remains a mystery for optimal nutrient absorption. But the study did determine that an addition of fat helped.
"In the absence of other sources of fat," the results continued, "the amount of fat in fat-free and reduced-fat salad dressings can be limiting in terms of the bioavailability of carotenoids." In other words, limiting the fat in your salad is limiting the health of your vegetables, too.
If you hate salad dressing, there are other ways to add dietary fat to your healthy meal. Avocados, nuts and seeds, and full-fat cheeses could add additional benefit to your salad in the absence of oil or dressing. But if you're a fan of a nice, creamy Caesar, the fatty, rich version could be your healthiest option.