Why Adding Olive Oil to Kale Helps Maximize Its Nutrients

Key Takeaways

• Pairing kale with olive oil helps the body absorb more of its fat-soluble carotenoids and vitamin A.
• Olive oil improves carotenoid absorption more effectively than coconut oil.
• Using 1–2 tablespoons of olive oil can boost nutrient absorption and make kale easier to digest.

There is a simple way to make kale even more nutritious: pair it with olive oil. 

Kale, often called a “superfood,” has high amounts of vitamins A, C, and K. A new study published in the journal Food Nutrition showed that eating kale with olive oil helps your body absorb more of the leafy green’s nutrients.

Why Olive Oil Helps You Absorb Nutrients in Kale

Using a simulated human gastrointestinal tract, researchers found that pairing either raw or cooked kale with oil enhances the absorption of carotenoids—antioxidants that can protect the body against free radicals and oxidative stress.

“The key nutrients in kale—especially carotenoids—are fat-soluble. That means they don’t dissolve well in the watery environment of the gastrointestinal tract when kale is eaten on its own, which greatly limits how much our bodies can absorb,” Ruojie Vanessa Zhang, PhD, co-author of the study and assistant professor in the Division of Food, Nutrition, and Exercise Sciences at the University of Missouri-Columbia, told Verywell in an email.

An easy way to get these benefits is to pair kale with an oil-based dressing or sauce. Oil facilitates the absorption process because, after it is broken down in the gut, it forms structures called “mixed micelles” that help solubilize and transport carotenoids across the intestinal lining, thereby boosting absorption, Zhang explained.

Olive Oil Has a Slight Edge Over Coconut Oil

You may not get the same absorption boost if you pair your kale with a medium-chain fatty acid like coconut oil instead of a long-chain fatty acid like olive oil.

Long-chain fatty acid oils form larger mixed micelles, which help make the nutrients in kale soluble. Medium-chain triglyceride oils don’t have this effect, Zhang said.

A small 2023 study compared coconut oil and olive oil on the absorption of carotenoids from a spinach and tomato salad. The findings showed that olive oil improves carotenoid absorption more than coconut oil.

“People often think adding oil makes vegetables ‘less healthy,’ but healthy fats actually help the body absorb key nutrients. The goal isn’t to avoid fat, it’s to choose the right kind and use it in moderation,” Melissa Mroz-Planells, DCN, RDN, a Seattle-based registered dietitian and spokesperson for the Academy of Nutrition and Dietetics, who was not involved in the research, told Verywell in an email.

How Much Oil Should You Use?

Although the research did not specify exactly how much olive oil to use, you don’t need to saturate the kale in oil for the nutrient boost.

One to two tablespoons of oil is generally enough. Try massaging a few handfuls of kale with this amount of olive oil before adding the greens to a salad, said Elizabeth Traxler, MS, RDN, LD, an outpatient clinical dietitian at University Hospitals in Cleveland.

In addition to the absorption boost, massaging kale with oil provides additional benefits.

“This method helps to break down the fibers of the kale, making it easier to digest and more palatable than eating the kale without the oil,” Traxler said.

Healthy Fat Helps You Absorb Certain Vitamins

Since the new research was conducted in a laboratory with a model GI tract, more human studies are needed to confirm exactly what happens when you eat and digest kale and olive oil.

“In general, most fat-soluble nutrients are better absorbed when paired with a little dietary fat,” said registered dietitian Mroz-Planells.

Vitamins A, D, E, and K are all fat-soluble. Lycopene, a fat-soluble antioxidant in tomatoes and red bell peppers, also benefits from being paired with olive oil.

But, even if you don’t want to use oil, you can still get plenty of vitamins, minerals, and fiber from kale without the oil, she added.

“Enjoy them in a variety of ways. Eating greens both raw and cooked, and pairing them with small amounts of healthy fats, helps you get a wider range of nutrients and flavors,” Mroz-Planells said.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

1. Zhu H, McClements DJ, Zhang Z, Zhang R. Culinary strategies for improving carotenoid bioaccessibility in kale: the role of thermal processing and excipient emulsions. Food Nutr. 2025;1(2):100049. doi:10.1016/j.fnutr.2025.100049

2. Yao Y, Yang Z, Yin B, Goh HM, Toh DWK, Kim JE. Effects of dietary fat type and emulsification on carotenoid absorption: a randomized crossover trial. The Am J Clin Nutr. 2023;117(5):1017-1025. doi:10.1016/j.ajcnut.2023.03.011

3. Harvard Health Publishing. Nutritional power couples.

4. Harvard T.H. Chan School of Public Health. Vitamins and minerals.

By Stephanie Brown

Brown is a nutrition writer who received her Didactic Program in Dietetics certification from the University of Tennessee at Knoxville. Previously, she worked as a nutrition educator and culinary instructor in New York City.

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