Once merely a decorative addition to Pizza Hut salad bars in the 1990s, kale has skyrocketed in popularity over the past twenty years. It is now a staple ingredient known for its impressive nutritional benefits, often featured in salads, kimchi bowls, pasta, soups, and smoothies.

“Kale’s popularity stems from both its health benefits and its versatility; it can be eaten raw, baked, blended, or sautéed,” explains Caroline Susie, a registered dietitian and national spokesperson for the Academy of Nutrition and Dietetics. “It is packed with vitamins and minerals while being low in calories, plus it’s tasty and visually appealing.”

These benefits contribute to a thriving global kale market estimated to be worth over $120 million, much of which can be attributed to the popularity of kale chips.

Let’s explore what kale is, its numerous health advantages, and why some individuals should be cautious about consuming it in large amounts.

Understanding Kale

Kale belongs to the Brassica family of cruciferous vegetables, which includes cabbage, cauliflower, and broccoli. “It represents a leafy green with numerous varieties,” says Susie. There are over 150 kale types, with curly kale being the most common for salads, lacinato kale (also called dinosaur or Tuscan kale) often used for kale chips, and Redbor kale typically found in smoothies, pasta, and soups. Ornamental kale is popular as a decorative feature in floral arrangements. Other notable varieties include red Russian, blue ridge, scotch, and winterbor, as well as dwarf and baby kale.

Kale is a relatively simple crop to cultivate and is available all year round. China is the leading producer globally, with Canada and the U.S. also growing significant amounts. Within the U.S., California is the top producer, followed closely by Georgia, New Jersey, and Texas, according to The Produce Reporter.

Is Kale Beneficial for Your Health?

Regardless of its source or variety, kale is packed with health benefits. A single cup of raw kale provides protein, fiber, magnesium, phosphorus, zinc, and an especially high amount of calcium and potassium, according to the U.S. Department of Agriculture.

“The significant calcium content in kale helps maintain strong bones and teeth, while potassium aids in cell hydration and supports energy production for daily activities,” notes Dr. Carolyn Newberry, an attending physician and nutrition scientist at Weill Cornell Medical Center in New York City.

“Kale is also rich in vitamins A, C, and K and contains numerous antioxidants,” adds Susie. Vitamin A supports eye health, vitamin C enhances your immune system, and vitamin K is crucial for blood clotting and healing, as well as maintaining bone health. “Additionally, kale is beneficial for weight loss since it is very low in calories (just 8 calories per cup!) and high in fiber, which helps you feel full longer.”

Studies suggest that kale may also assist in lowering LDL (bad) cholesterol levels and is abundant in compounds like sulforaphane and indole-3-carbinol, which may help reduce cancer risk.

Is Daily Kale Consumption Safe?

Even with its many advantages, some individuals should avoid excessive kale consumption. It contains raffinose, a sugar that can be hard for the body to digest, and its high fiber content may lead to bloating, constipation, and stomach discomfort in large quantities—particularly in those with sensitive digestive systems or conditions like IBS.

“Individuals with advanced kidney disease or kidney stones should also be careful regarding their kale intake due to its oxalate and potassium levels,” advises Newberry. “Moreover, many medications can interact with vitamin K, including antacids, blood thinners, and antibiotics,” adds Susie; “it’s best to consult your pharmacist, doctor, or dietitian for tailored advice.”

As long as these considerations are taken into account, “kale is safe for most healthy individuals,” she concludes, “and it’s a fantastic addition to a balanced diet.”