Spinach is a leafy green vegetable.

Scientifically known as as Spinacia oleracea, spinach belongs to the amaranth family and is related to beets and quinoa.

Spinach originated in Persia, but is now produced mostly in the US and China.

It is loaded with nutrients and antioxidants, and considered to be very healthy.

Eating spinach may benefit eye health, reduce oxidative stress, help prevent cancer and reduce blood pressure levels.

There are many ways to prepare spinach. You can buy it canned or fresh, and then eat it cooked or raw. It is delicious either on its own or in other dishes.

By weight, spinach consists of 91.4% water, 3.6% carbs and 2.9% protein. There are 23 calories in 100 grams (3.5 oz) of spinach.

The table below contains information on the nutrients found in spinach ().

Nutrition Facts: Spinach, Raw — 100 grams

Water91 %
Protein2.9 g
Carbs3.6 g
Sugar0.4 g
Fiber2.2 g
Fat0.4 g
Saturated0.06 g
Monounsaturated0.01 g
Polyunsaturated0.17 g
Omega-30.14 g
Omega-60.03 g
Trans fat~

Most of the carbs in spinach consist of fiber.

Spinach also contains 0.4% sugar, mostly glucose and fructose ().


Spinach is high in insoluble fiber, which may benefit health in several ways ().

Insoluble fiber adds bulk as food passes through the digestive system. This may help prevent constipation.

Bottom Line: Spinach is low in carbs, but high in insoluble fiber. This type of fiber may have benefits for digestion.

Spinach is an excellent source of many vitamins and minerals:

  • Vitamin A: Spinach is high in carotenoids, which the body can turn into vitamin A (3).
  • Vitamin C: Vitamin C is a powerful antioxidant that promotes skin health and immune function.
  • Vitamin K1: Vitamin K is essential for blood clotting, and one spinach leaf contains over half of your daily need.
  • Folic acid: Also known as folate, or vitamin B9. It is essential for normal cellular function and tissue growth, and is very important for pregnant women.
  • Iron: Spinach is an excellent source of this essential mineral. Iron helps create hemoglobin, which brings oxygen to the body's tissues.
  • Calcium: Calcium is essential for bone health. This mineral is also a crucial signalling molecule for the nervous system, heart and muscles.

Spinach also contains several other vitamins and minerals, such as potassium, magnesium, and vitamins B6, B9 and E.

Bottom Line: Spinach is an extremely nutrient-rich vegetable. It contains high amounts of carotenoids, vitamin C, vitamin K, folic acid, iron and calcium.

Spinach contains several important plant compounds, including:

  • Lutein: Lutein is linked to improved eye health ().
  • Kaempferol: This antioxidant is linked to a decreased risk of cancer and chronic disease ().
  • Nitrates: Spinach contains high amounts of nitrates, which may promote heart health (, ).
  • Quercetin: This antioxidant may ward off infection and inflammation. Spinach is one of the richest dietary sources of quercetin (8, , ).
  • Zeaxanthin: Like lutein, zeaxanthin can also improve eye health ().
Bottom Line: Spinach contains many plant compounds that can improve health. These include lutein, kaempferol, nitrates, quercetin and zeaxanthin.

Spinach is extremely healthy and has been linked to numerous health benefits.

It has been shown to help decrease oxidative stress, improve eye health, aid in cancer prevention and help regulate blood pressure levels.

Oxidative Stress

Free radicals are byproducts of metabolism. They can cause oxidative stress, which triggers accelerated aging. This also increases the risk of cancer and diabetes ().

However, spinach contains antioxidants, which fight oxidative stress and help reduce the damage it causes.

One controlled trial on 8 healthy people found that spinach helped prevent oxidative damage ().

Although the study mentioned above was quite small, the findings are backed up by other animal and human studies (, ).

Bottom Line: Spinach has been shown to reduce oxidative stress. The antioxidants found in spinach may help fight aging and reduce the risk of cancer and diabetes.

Eye Health

Spinach contains high amounts of zeaxanthin and lutein, which are the carotenoids responsible for color in some vegetables.

Human eyes also contain high quantities of these pigments. They help protect our eyes from the damage caused by sunlight ().

Additionally, several studies have indicated that zeaxanthin and lutein work to prevent macular degeneration and cataracts, which are the leading diseases that cause blindness (, , , ).

These compounds may even be able to reverse existing damage (, ).

Bottom Line: Spinach contains lutein and zeaxanthin, which are beneficial for eye health. These compounds may help block or reverse the damage caused by sunlight.

Cancer Prevention

Spinach contains two components, MGDG and SQDG, which may slow down cancer growth.

In one study, these compounds helped slow tumor growth in a human's cervix. They also decreased the size of the tumor (22, ).

Several human studies link spinach consumption to a reduced risk of prostate cancer. Eating this leafy green may also help prevent breast cancer (, ).

Another animal study supports this claim. Its findings indicate that spinach might help suppress cancer formation ().

Additionally, spinach contains high amounts of antioxidants, which may also aid in cancer prevention ().

Bottom Line: Spinach contains high amounts of antioxidants and other compounds that may suppress the growth of human cancer cells.

Blood Pressure

Spinach contains high amounts of nitrates, which have been shown to help moderate blood pressure levels and decrease the risk of heart disease (28, 29).

One randomized, controlled crossover trial of 27 people found that eating spinach effectively lowered blood pressure levels ().

Several other studies also indicate that spinach may help moderate blood pressure levels, which leads to improved heart health (, ).

Bottom Line: Spinach contains high amounts of nitrates, which may help regulate blood pressure levels. This should lead to improved heart health and a reduced risk of heart disease.

Spinach is generally considered to be very healthy. However, it may cause adverse effects in some individuals.

Kidney Stones

These small stones are caused by acid and mineral salt buildup. The most common variety is calcium stones, which often consist of calcium oxalate.

Spinach is high in both calcium and oxalates, so people who tend to develop kidney stones should not eat large amounts (, ).

Blood Clotting

Spinach contains very high amounts of vitamin K1.

Vitamin K1 serves several functions in the body, but is best known for its role in blood clotting.

People who are taking blood-thinners, such as warfarin, may want to closely monitor their vitamin K intake or avoid leafy greens altogether ().

Bottom Line: People who are prone to kidney stones may want to avoid spinach. It is also very high in vitamin K1, which can be a problem for people who take blood thinning medications.

Spinach is a nutritious, leafy green vegetable.

Eating spinach has been shown to benefit health in several ways, and it contains high amounts of all sorts of powerful nutrients.

Spinach may decrease oxidative stress, improve eye health and help prevent heart disease and cancer.

Without a doubt, spinach is an incredibly healthy food.