Kale
Kale is considered a "superfood" with a significantly high calcium content. According to the United States Department of Agriculture (USDA), every 100 grams of kale contains about 150 mg of calcium. In particular, the calcium in kale is better absorbed than milk because it does not contain oxalic acid - a calcium absorption inhibitor commonly found in green leafy vegetables.
Spinach
Spinach provides about 99 mg of calcium per 100 grams. In addition, this vegetable is rich in vitamin K and magnesium, which aids in calcium absorption and maintains bone density. Research in the Journal of Bone and Mineral Research highlights that regular intake of spinach in the diet can improve bone health.
Broccoli
Broccoli is not only rich in antioxidants, but also contains a significant amount of calcium, about 47 mg/100 grams. According to the Harvard Nutrition Institute, this vegetable has a high calcium absorption rate and is a great choice for people with allergies or lactose intolerance.
Bok choy
Bok choy provides about 105 mg of calcium per 100 grams. A study in the American Journal of Clinical Nutrition shows that Bok choy is not only rich in calcium but also contains vitamin C and beta-carotene, which helps strengthen the immune system and protect bones and joints.
Spinach
Amaranth contains up to 215 mg of calcium per 100 grams, much higher than cow's milk (only about 125 mg of calcium per 100 ml). According to the World Health Organization (WHO), amaranth also provides iron and potassium, helping to maintain cardiovascular and bone health.
Collard greens
Collard greens are a rich source of calcium, with about 232 mg/100 grams, far exceeding many animal food sources. Research from the National Institutes of Health (NIH) shows that this vegetable is also rich in vitamin K, which helps activate osteocalcin, an important protein in bone building.
