Kale has become the darling of the health food world in recent years, but its superfood predecessor spinach still has some significant advantages over the trendy green leafy vegetable. Though both spinach and kale are nutrient dense foods, spinach packs more of a nutritional punch for fewer calories per serving. Here’s a detailed comparison of the two to help you decide which one deserves more real estate in your fridge.
Let’s start by looking at the basic nutritional profiles of raw spinach and kale. Here’s how they stack up per 100 grams (about 3.5 ounces):
|Vitamin A||469% DV||206% DV|
|Vitamin C||28% DV||134% DV|
|Vitamin K||482% DV||704% DV|
|Calcium||10% DV||18% DV|
|Iron||20% DV||7% DV|
|Potassium||24% DV||17% DV|
As you can see, spinach has significantly fewer calories per serving compared to kale. It also has nearly double the amount of vitamin A and iron. Kale beats out spinach in vitamin C and vitamin K, but spinach is still a very good source of both nutrients.
One area where spinach trumps kale is in its content of cancer-fighting compounds. Spinach contains a flavonoid called quercetin, which has strong anti-inflammatory and antioxidant properties. Quercetin has been shown to help reduce damage caused by free radicals in the body and inhibit the growth of cancer cells.
Spinach is also high in carotenoids such as beta-carotene, lutein, and zeaxanthin. These compounds are associated with a decreased risk of lung, breast, uterine, and skin cancers.
While kale does contain some quercetin and carotenoids as well, the total quantities are significantly higher in spinach. Adding more spinach to your diet can help boost your intake of these protective plant nutrients.
Managing Blood Sugar
Spinach has an edge over kale when it comes to managing blood sugar levels and preventing type 2 diabetes. It has a very low glycemic index, meaning it doesn’t cause large spikes in blood sugar. The alpha-lipoic acid and magnesium in spinach also help regulate glucose metabolism.
A 2013 study found that individuals with type 2 diabetes who consumed puréed spinach as part of a mixed vegetable juice saw significant reductions in fasting blood glucose levels and A1c levels compared to those drinking vegetable juice without spinach.
Kale is certainly a diabetic-friendly vegetable as well, but spinach packs a greater overall anti-diabetic punch. Adding generous amounts of spinach to your diet can benefit blood sugar control, especially for those managing diabetes.
Here’s another win for spinach. Its rich supply of carotenoids like lutein and zeaxanthin promote eye health and help prevent age-related macular degeneration and cataracts. These compounds protect the eyes from damage caused by UV light and blue light from digital devices.
Kale has a respectable amount of lutein and zeaxanthin, but spinach serves up way more. Aim for 1-2 servings of spinach per day to keep your eyes in tip-top shape.
Spinach delivers more bone-strengthening vitamin K and magnesium than kale. One cup of raw spinach has over three times as much vitamin K as an equal amount of kale.
Vitamin K promotes osteotrophic activity, meaning it stimulates bone growth and increases bone density. This makes your bones stronger and less likely to fracture. Magnesium also plays a role in preventing bone loss.
If you’re looking to reduce your risk of osteoporosis, be sure to include spinach in your vegetable rotation. The more often you eat it, the better for your bone health.
Chronic inflammation is at the root of most modern diseases, including heart disease, autoimmune disorders, and even depression. Spinach contains specialized metabolites called glycoglycerolipids that have a potent anti-inflammatory effect in the body.
Animal studies have found spinach glycoglycerolipids can reduce levels of inflammatory cytokines, nitric oxide, and other inflammatory markers. The omega-3 fatty acid alpha-linolenic acid found in spinach also fights inflammation.
Kale has minimal amounts of glycoglycerolipids compared to spinach. So spinach is arguably the better choice for natural anti-inflammatory benefits.
Here’s another feather in spinach’s cap – it excels at helping remove toxins from the body. Spinach is rich in glutathione, a special antioxidant that is crucial for liver detoxification. It helps bind to heavy metals and other toxic substances so they can be safely eliminated.
Spinach also activates Phase II detox enzymes to further speed up the detox process. The folate in spinach helps rid the body of unnatural chemicals and pollutants as well.
Kale promotes detox too, but spinach is the winner for superior detox-boosting abilities. Working more spinach into your diet enhances your natural detoxification system.
Storage and Preparation
When it comes to storage, kale tends to outlast spinach. Kale leaves are heartier and stand up better to time in the fridge. Spinach is more delicate and prone to wilting after 4-5 days.
However, spinach has an advantage when cooking. It reduces down in size more than kale when sautéed or steamed. A giant pile of raw kale can cook down to a small side portion. Kale also takes longer to become tender.
Spinach has great versatility in preparations. Both raw and cooked spinach is delicious and adapts well to any dish. It blends smoothly for green smoothies, while sturdy kale requires more liquid for smooth results.
When all is said and done, spinach beats out kale in several nutritional categories. It has a lower calorie count, more iron, more vitamin A, and higher anti-cancer and anti-diabetic properties. Kale does excel at a few specific nutrients like vitamin C and vitamin K, but spinach still contains respectable amounts.
This isn’t to say you should abandon kale completely. Both spinach and kale are extremely healthy foods that should be regularly included in a balanced diet. But if you had to choose one as the “most nutritious” vegetable, spinach would take the prize.
Add spinach to an omelet, blend into a smoothie, sauté it with garlic, or simply use it as the base of a fresh salad. However you enjoy it, upping your spinach intake will provide your body with an abundance of nutrition and health benefits.