It's the perfect season to enjoy a leafy salad, however with many of us concerned about maintaining our summer bodies you may be tempted to save a few calories by skipping the dressing. However new research published in the American Journal of Clinical Nutrition has revealed that adding fat to your salad makes it's healthier.
Adding oil to your salad could increase the absorption of nutrients including vitamins A, E and K, which have been previously associated with cancer prevention and improved vision, say researchers.
It was observed that nutrient absorption increases proportionally to the amount of oil added. Professor Wendy White, lead author of the paper, says:
"The best way to explain it would be to say that adding twice the amount of salad dressing leads to twice the nutrient absorption."
Findings support previous research
These findings are supported by previous research that has shown that adding fat to vegetables in the form of oil, nuts or cheese gives the absorption of fat-soluble nutrients a boost - for example lycopene in tomatoes and beta carotene in carrots.
The study, funded by Unilever, comprised 12 healthy, non-smoking women between 19 and 39 years old. Only women were included in the trial due to their faster speed of nutrient absorption and metabolism.
The salads given to participants had equivalent vegetable composition including 48g of spinach, 48g of romaine lettuce, 66g of grated carrot and 85g of cherry tomatoes. All salads had different dressings containing different amounts of soybean oil. The amounts studied were 0, 2, 4, 8 or 32g.
Blood samples were taken and measured to identify the extent of nutrient absorption. Across the 0 - 32g range, the amount of oil was linearly related to the uptake of the key nutrients.
2 tablespoons of oil is needed for maximum absorption
Maximum absorption occurred at 32g, which is the equivalent of around two tablespoons (it is not recommended to drench your salad in any more than this!) Those participants who were asked to eat the same salad , the team found the absorption of nutrients was much lower.
"For most people, the oil is going to benefit nutrient absorption. The average trend which was statistically significant, was for increased absorption."