Broccoli (Brassica oleracea) is a cruciferous vegetable related to cabbage, kale, cauliflower, and Brussels sprouts.

These vegetables are known for their beneficial health effects.

Broccoli is high in many nutrients, including fiber, vitamin C, vitamin K, iron, and potassium. It also boasts more protein than most other vegetables.

This green veggie can be enjoyed both raw and cooked, but recent research shows that gentle steaming provides the most health benefits (1, 2).

This article tells you everything you need to know about broccoli.

Raw broccoli contains almost 90% water, 7% carbs, 3% protein, and almost no fat.

Broccoli is very low in calories, providing only 31 calories per cup (91 grams).

The nutrition facts for 1 cup (91 grams) of raw broccoli are (3):

  • Calories: 31
  • Water: 89%
  • Protein: 2.5 grams
  • Carbs: 6 grams
  • Sugar: 1.5 grams
  • Fiber: 2.4 grams
  • Fat: 0.4 grams

Carbs

Broccoli’s carbs mainly consist of fiber and sugars.

The sugars are fructose, glucose, and sucrose, with small amounts of lactose and maltose (4).

However, the total carb content is very low, with only 3.5 grams of digestible carbs per cup (91 grams).

Fiber

Fiber is an important part of a healthy diet.

It can promote gut health, help prevent various diseases, and aid weight loss (5, 6).

One cup (91 grams) of raw broccoli provides 2.3 grams of fiber, which is about 5–10% of the Daily Value (DV) (7).

SUMMARY Broccoli is low in digestible carbs but provides a decent amount of fiber, which promotes gut health and may reduce your risk of various diseases.

Proteins are the building blocks of your body, necessary for both growth and maintenance.

Broccoli is relatively high in protein, which makes up 29% of its dry weight, compared to most vegetables.

However, because of its high water content, 1 cup (91 grams) of broccoli only provides 3 grams of protein.

SUMMARY Broccoli is higher in protein than most vegetables. That said, the amount of protein in each serving is relatively low.

Broccoli contains a variety of vitamins and minerals, including (8, 9, 10, 11, 12, 13):

  • Vitamin C. An antioxidant, this vitamin is important for immune function and skin health. A 1/2-cup (45-gram) serving of raw broccoli provides almost 70% of the DV.
  • Vitamin K1. Broccoli contains high amounts of vitamin K1, which is important for blood clotting and may promote bone health.
  • Folate (vitamin B9). Particularly important for pregnant women, folate is needed for normal tissue growth and cell function.
  • Potassium. An essential mineral, potassium is beneficial for blood pressure control and heart disease prevention.
  • Manganese. This trace element is found in high amounts in whole grains, legumes, fruits, and vegetables.
  • Iron. An essential mineral, iron has many important functions in your body, such as the transport of oxygen in red blood cells.

Broccoli also contains numerous other vitamins and minerals in smaller amounts. In fact, it provides a little bit of almost every nutrient you need.

SUMMARY Broccoli is high in many vitamins and minerals, including folate, potassium, manganese, iron, and vitamins C and K1.

Broccoli is rich in various antioxidants and plant compounds, which contribute to its health benefits. These include (14, 15, 16, 17, 18, 19, 20):

  • Sulforaphane. One of the most abundant and extensively studied plant compounds in broccoli, sulforaphane may protect against various types of cancer.
  • Indole-3-carbinol. A unique nutrient found in cruciferous vegetables, this compound may help fight cancer.
  • Carotenoids. Broccoli contains lutein, zeaxanthin, and beta carotene, which may all contribute to better eye health.
  • Kaempferol. An antioxidant with many benefits for health, this compound may protect against heart disease, cancer, inflammation, and allergies.
  • Quercetin. This antioxidant has numerous benefits, including lowering blood pressure in people with high levels.
SUMMARY Broccoli is high in many plant compounds that have been associated with health benefits. The most abundant one is sulforaphane.

Cruciferous vegetables like broccoli provide sulfur-containing compounds that are responsible for their often pungent taste (21).

These bioactive compounds may have numerous health benefits.

Cancer prevention

Cancer is characterized by the rapid growth of abnormal cells and is often linked to oxidative stress (22).

Broccoli is loaded with compounds that are believed to protect against cancer.

Observational studies suggest that the consumption of cruciferous vegetables, including broccoli, is linked to a reduced risk of many cancers, including lung, colorectal, breast, prostate, pancreatic, and gastric cancers (23, 24, 25, 26).

A unique family of plant compounds called isothiocyanates sets cruciferous vegetables apart from other veggies.

Studies suggest that Isothiocyanates affect liver enzymes, reduce oxidative stress, decrease inflammation, stimulate your immune system, and combat the development and growth of cancer (27, 28, 29).

The main isothiocyanate in broccoli, sulforaphane, acts against the formation of cancer at the molecular level by reducing oxidative stress (16, 30, 31).

Sulforaphane occurs at 20–100 times higher amounts in young broccoli sprouts than in full-grown heads of this vegetable (32).

Though broccoli supplements are also available, they may not contribute an equivalent amount of isothiocyanates and thus may not give the same health benefits as eating whole, fresh broccoli (33, 34).

Lower cholesterol levels

Cholesterol has many important functions in your body.

For example, it is a key factor in the formation of bile acids, which help you digest fat. Bile acids are formed in your liver, stored in your gallbladder, and released into your digestive system whenever you eat fat.

Afterward, the bile acids are reabsorbed into your bloodstream and used again.

Substances in broccoli bind with bile acids in your gut, increasing their excretion and preventing them from being reused (35).

This results in the synthesis of new bile acids from cholesterol, reducing total levels of this marker in your body.

This effect has been linked to a reduced risk of heart disease and cancer (2).

According to one study, steamed broccoli is particularly useful for lowering cholesterol levels (2).

Eye health

Impaired eyesight is a common consequence of aging.

Two of the main carotenoids in broccoli, lutein and zeaxanthin, are associated with a decreased risk of age-related eye disorders (36, 37).

Vitamin A deficiency may cause night blindness, which can be reversed with improved vitamin A status (38).

Broccoli contains beta carotene, which your body converts into vitamin A. This vegetable may thus boost eyesight in individuals with a low vitamin A intake.

SUMMARY Broccoli’s isothiocyanates may improve many risk factors for disease and reduce your risk of cancer. What’s more, this vegetable may help lower cholesterol and boost eye health.

Broccoli is usually well tolerated, and allergy is rare. However, some considerations are worth mentioning (39).

Thyroid problems

Broccoli is considered a goitrogen, which means that high amounts may harm the thyroid gland in sensitive individuals.

Cooking this vegetable on high heat can reduce these effects (40).

Blood thinners

Individuals taking the blood thinner warfarin should consult with their healthcare practitioner before increasing their broccoli intake because its high vitamin K1 content may interact with this medication (41).

SUMMARY Broccoli is usually well tolerated. Still, it may have undesirable effects on the thyroid in some people and may interfere with blood-thinning medicine.

Broccoli is one of the world’s most popular vegetables. It is easy to prepare and edible both raw and cooked.

It is high in many nutrients, including a family of plant compounds called isothiocyanates, which may have numerous health benefits.

It is also a decent source of fiber and higher in protein than most other vegetables.

If you’re looking for a health boost, consider adding this cruciferous vegetable to your diet today.