Nutrition facts label: A good salad has a lot of kale, according to a study in the American Journal of Clinical Nutrition.
And while the amount of kale per serving is not as important as the total amount of the food in it, the nutrition content can be an important factor, the authors write.
“It seems that the amount you get from a single serving of salad is more important than the total weight of the salad, and that’s because the amount in a single salad is not the same as the amount added to the salad,” says senior author Christopher J. Lutz, a professor of nutritional sciences and director of the Center for Nutritional Neuroscience at the University of Illinois at Chicago.
“For example, if you eat two cups of salad and one cup of dressing, you’ll get more than twice as much vitamin K as if you ate a single cup of salad.”
Kale has a high protein content, which is not surprising, says Lutz.
“But the protein content of kale varies depending on the cultivar, which also means that you can get more or less protein than you think you’re getting,” he says.
“Kale is also high in phytonutrients, which can help with some aspects of inflammation and inflammation-related disease.
That’s one reason that people who are overweight and obese can get better health outcomes than people who don’t have diabetes.”
“We found that the best way to eat kale is to eat it all,” says Lutz.
“If you want to get more vitamin K, you have to eat a lot more kale than you’d think.”
Lutz and his colleagues found that eating kale with pasta and rice instead of plain rice or pasta could provide more vitamin E and C than kale, and kale with tomatoes instead of spinach could provide a higher total protein content.
The researchers also found that kale can be consumed in small quantities in salads.
“You could eat a couple of ounces of kale in a bowl of soup or a bowl with salad and a little salad in the middle,” Lutz says.
To get the most nutrition out of kale for a meal, the researchers suggest eating a serving at a time and counting the total of the servings, which could include vegetables, whole grains, and fruit.
To measure the nutritional content of a given salad, the team measured the amounts of fat and protein in each serving, as well as its composition.
“This is an important step in understanding the health effects of different types of vegetables,” says study co-author Rachael Pugh, an associate professor of food science and nutrition at the Johns Hopkins Bloomberg School of Public Health.
The authors found that a serving of kale provided about half the nutritional value of a serving with spinach, as did a serving that included half a cup of white potatoes, half a small handful of almonds, and two cups hot sauce.
The team also found a similar relationship between the protein and fat content of individual kale varieties and the amount, but not the total volume, of kale.
“That’s interesting,” says Pugh.
“We’re seeing that some types of kale can provide more than others.
It seems like it’s important to be able to measure the different types in a lot smaller doses.”
“There’s more to kale than just the vitamin K content,” adds Lutz with a laugh.
“In terms of health, it’s a really important source of calcium and vitamin D, which are important for good eye health.”