Stories about spinach often include the story of Popeye, the sailor who gained great powers by munching on whole cans of spinach. But if you need to bring a comic book character into the conversation about healthy eating, consider the Hulk.

In addition to their common color, spinach is one of the most nutritious plants of its kind.

“I think spinach is very unique,” says Dr. Joseph Roberts, assistant professor of nutrition at Arizona State University in Phoenix.

Dark leafy vegetables are recommended as part of a healthy eating pattern. “They’re primarily considered nutritious countries” because they’re nutritious, Roberts said. In other words, you can get plenty of nutrients without eating a lot of calories.

Roberts, lead author of an academic review on spinach published in the journal Food & Function in 2016, noted that spinach is a good source of vitamins A, C, and B9 (folate).

The nutritional value of spinach can be flashy. According to the United States Department of Agriculture, one cup of raw spinach has only 7 calories. However, it provides 121% of the vitamin K that men should consume daily and 161% of the amount recommended for women. The amount of vitamin K in spinach is about 4 times that of lettuce, about 5 times that of broccoli, and about 8 times that of cabbage.

Each cup of cooked spinach provides 129% of the daily recommended amount of vitamin A for women and 105% for men.

Spinach also contains more minerals, magnesium, potassium, and iron than cabbage, lettuce, or broccoli.

Leafy green vegetables are also rich in phytochemicals, which are compounds found primarily in plants that have a variety of health-promoting properties. They have long been known to function as antioxidants that help fight inflammation and aging, Roberts said. Only recently have researchers begun to seriously consider how they can do even more.

Spinach is one of the best plant sources of lutein, a type of plant-based pigment known as a carotenoid, which is associated with improved eye and brain health.

Some studies have focused on spinach’s thylakoids, the part of the plant cell that converts sunlight into energy. Extracts made from spinach thylakoids have been shown to increase satiety, or the feeling of being full after a meal, but Roberts said such effects have not been studied in detail with whole spinach.

But spinach is high in fiber and “most Americans need to increase their intake,” he said. Fiber has been shown to help prevent conditions such as heart disease and diabetes. Raw spinach contains just over 0.5 grams of fiber per cup. Boiled spinach provides more than 4 grams per cup. (Spinach is 91% water, and cooked spinach has more leaves than the same volume of raw spinach.)

So, unless you’re the kid in one of the New Yorker’s most famous cartoons, what’s not to like? “Spinach” was once used as a synonym for “nonsense,” but considering There are some serious issues that need to be addressed.

Roberts says spinach is high in oxalates, which can interfere with your body’s ability to absorb minerals. In fact, spinach is rich in calcium, and oxalate binds to calcium in the intestines, he said.

“This can lead to the formation of kidney stones in certain people,” he said. People who are prone to kidney stones may be given a low-oxalate diet. Roberts says boiling spinach can reduce oxalate intake.

Spinach also contains purines, which are converted to uric acid in the body. Professor Roberts said that although uric acid can trigger attacks in people with gout, “research shows that consuming spinach has little effect on the risk of gout attacks.”

Vitamin K, which plays an important role in blood clotting, can interfere with warfarin, which thins the blood. Roberts said it’s less of an issue with newer blood thinners, but people taking warfarin need to “consistently get vitamin K,” which helps stabilize warfarin levels.

And if you do decide to serve spinach, perhaps don’t use Popeye as a role model. Aside from the health risks associated with pipe smoking, he may be consuming unnecessary sodium. One cup of canned food contains nearly 440 to 750 milligrams. The American Heart Association recommends limiting sodium intake to 2,300 mg per day, and the ideal limit for most adults is 1,500 mg per day.

For all fruits and vegetables, Roberts said, “The fresher, the better.” So at the grocery store, I asked for fresh spinach bundles rather than bags or plastic containers, based on the assumption that the fresh spinach bundles were probably more recently harvested.

If you buy raw, consume it immediately, he said. “Don’t leave it in the refrigerator for too long, as the nutritional content will be reduced.” Frozen foods are typically processed closer to the point of harvest, so they may actually contain higher nutrient levels, he said. Ta.

How you prepare your spinach is important. “Cooking can affect the nutritional content of spinach,” he said. Boiling can reduce the content of vitamins B and C and some phytochemicals. These compounds end up in cooking water, so “one way to recover it is to use that cooking water as a base for soups,” he said.

Popeye will be happy to know that spinach pairs well with olive oil. Vitamins K and A, as well as lutein, require small amounts of fat to be absorbed by the body. So Roberts recommended sauteing spinach in a little oil or eating it raw with a little oil.

Then there are smoothies. “This is actually how I eat spinach every day,” said Roberts, who eats about 1 cup of spinach every morning. Chopping spinach may actually increase the bioavailability of lutein and other compounds, he said.

“But of course the important thing is to find a form of spinach that you enjoy, because they all offer some level of nutrition and benefit,” he said.