Spinach is a nutritious, high-fibre food that adds volume, colour, texture, vitamins, and minerals to recipes. Whether eaten cooked or raw, spinach is a nutrient-packed vegetable. However, if you're on blood thinners or have a history of kidney stones, you may be wondering whether or not spinach is safe to eat. Luckily, there is no reason to restrict your spinach intake as long as you're consistent and mindful in managing lifestyle factors related to these conditions.

Spinach Nutrition Facts

The USDA provides the following nutrition information for 3 cups of fresh spinach (85 grams).

Calories: 20

Fat: 0g

Sodium: 64.6 mg

Carbohydrates: 3g

Fibre: 2g

Sugars: 0g

Protein: 2g

Vitamin K: 410mcg

Vitamin C: 24mg

Carbs

Most of the carbohydrates in spinach are from fibre, making it a very filling vegetable. In 3 cups of raw spinach, two out of the three total carbohydrates come from fibre.

Spinach and other leafy greens may be considered "free" foods on low-carbohydrate diets because they provide fibre and are so low in calories.

Protein

In 3 cups of fresh spinach, there are 2 grams of protein. Spinach has almost as much protein as it does carbohydrates.

Fat

There is no fat in spinach.

Vitamins and Minerals

Three cups of fresh spinach provide a whopping 340% of your vitamin K needs. You'll also get 35% of your manganese requirements, 25% of vitamin C, 15% of iron, and 10% of potassium. Cooking spinach increases its concentration of vitamin A. You get 64% of your daily value in 1/2 cup of boiled spinach.

Health Benefits

Like most dark, leafy greens, spinach has nutrients that offer several health benefits. Spinach is a non-starchy vegetable that's perfect for anyone who is watching their carbohydrate intake or trying to boost their health.

Promotes Weight Management

Intake of spinach and other vegetables is significantly associated with a lower risk of weight gain. Some studies have suggested that consuming four servings of vegetables per day, instead of two, may reduce the risk of weight gain by up to 82%.

Reduces Cancer Risk

In addition to being packed with vitamins, fibre, and minerals, spinach contains chlorophyll, which is responsible for its green pigment. Chlorophyll has high antioxidant effects, suggesting promising benefits for cancer prevention.

Protects Eye Health

The vitamin A found in spinach plays a vital role in protecting eye health from oxidative damage. Vitamin A is a fat-soluble vitamin, so sauteing spinach with some healthy fat (like olive oil), or eating with other foods that contain fat (like eggs in an omelette) will improve absorption of the vitamin A in spinach. Spinach's combination of both vitamin A and vitamin C helps prevent age-related macular degeneration.

Prevents Hair Loss

Spinach is an excellent non-animal source of iron. Iron deficiency is a common cause of hair loss for women, which may be avoidable with an adequate intake of iron-rich foods, like spinach. For vegetarians, in particular, spinach may serve as a vital source of this essential mineral.

Enhances Blood Functions

Iron is also required for the prevention of anemia. Spinach supports the blood's ability to carry oxygen (through the proper formation of hemoglobin). Furthermore, vitamin C in spinach enhances the body's ability to absorb iron. Perhaps even more significant than its iron levels, spinach is exceptionally high in vitamin K. Vitamin K clots the blood to reduce excessive bleeding after an injury.

Allergies

Spinach is not a major allergen. Allergic reactions to spinach are uncommon but not impossible. Common food allergy symptoms include hives, vomiting, teary eyes, sneezing, and trouble breathing. If you suspect you have a spinach allergy, see your doctor for a proper evaluation.

Adverse Effects

Coumadin (warfarin) is a medication that is prescribed to heart patients to avoid unwanted blood clots. Since vitamin K is a crucial factor for blood clotting, it is important to be mindful of your intake of green leafy vegetables, such as spinach. To help Coumadin work effectively, vitamin K intakes should remain as consistent as possible. Substantial fluctuations in spinach intake will impact vitamin K levels and may increase or decrease the effect of Coumadin.

If you've experienced kidney stones, your doctor may advise you to avoid overeating spinach. Certain foods, like spinach, are high in oxalates. Ask your doctor if oxalates cause your type of kidney stones. Depending on the type of kidney stone, drinking plenty of water, avoiding sodium, and reducing your intake of meat might have a more significant impact on your risk of kidney stones than spinach will.

Varieties

There are three main types of spinach: savoury, crinkled leaf, and plain leaf. Each has several varieties within its class that vary in size and shape. Different types of spinach lend themselves favourably to different kinds of climates; therefore, fresh spinach is available all year long. Frozen and canned spinach can also be purchased all year.

Some water-soluble vitamins, such as vitamin C and B vitamins, are lost when cooking spinach.

When It's Best

Spinach can be grown in the spring or autumn. Spinach is harvested whenever the leaves are big enough to eat. The outer leaves are usually picked at about 3 inches long, and the inner leaves are left to mature. Once spinach begins flowering, the leaves tend to fall apart, so it's important to pick the leaves before flowering.

Raw spinach shrivels down considerably when cooking. Typically, a 10-ounce bag of spinach, for example, will condense to about 1.5 cups of cooked spinach.

Storage and Food Safety

Like most leafy greens, leaves should be crisp, tender, and green. Avoid wilted leaves or those with blemishes. Any yellow or browning leaves should be thrown out. If you are purchasing spinach in a bag or box, buy it as fresh as possible. The fresher a product is, the more nutritious it will be. You'll know your spinach has gone bad when it begins to wilt or starts to smell. It's always a good idea to wash fresh spinach before eating or cooking with it.

Fresh spinach should be used right away, within about 3 days. You can also freeze fresh greens. To do so, blanch your spinach in boiling water for one minute and then place it in an ice bath to cool. Next, wring out as much water as possible and form the spinach into single-serving balls, place in a ziplock bag in the freezer. Keep blanched spinach in the freezer for 8–12 months.

How to Prepare

Rinse spinach in cold water to remove all traces of grit from the leaves.

Spinach works well with moist cooking methods, but steaming and sauteing are most common. Be careful when cooking with oil, as spinach can act like a sponge and soak up a large portion of fat.

Spinach can also be used raw as a salad green or an ingredient in smoothies. Get creative and use spinach as a replacement for bread when making wraps, or as an addition to egg scrambles. Chop it and add it soups and casseroles or stuff food protein sources with it for a fibre and protein filling meal. Use spinach to make anything and everything, from dips to salads to casseroles, the options are endless.