Broccoli is is a cruciferous vegetable, known scientifically as Brassica oleracea.
It is related to cabbage, kale, cauliflower and Brussels sprouts.
These vegetables are known for their beneficial health effects, and are sometimes referred to as the "super veggies."
Broccoli is high in many nutrients, including fiber, vitamin C, vitamin K, iron and potassium. Broccoli also contains more protein than most other vegetables.
Broccoli can be enjoyed both raw and cooked, but recent research shows that gentle steaming provides the most health benefits (, ).
Raw broccoli contains almost 90% water, 7% carbs and 3% protein, and almost no fat.
Broccoli is very low in calories, providing only 31 calories per cup.
The table below contains information on all the main nutrients in broccoli ().
The carbohydrates in broccoli mainly consist of fiber and sugars.
The sugars are fructose, glucose and sucrose, with small amounts of lactose and maltose ().
However, the total carbohydrate content is very low, with only 3.5 grams of digestible carbohydrate per cup.
Fiber is an important part of a healthy diet.
It can promote gut health, help prevent various disease, and is linked to reduced body weight (, ).
1 cup of raw broccoli (91 g) provides 2.3 grams of fiber, which is about 5-10% of the recommended daily intake ().
Bottom line: Broccoli is low in digestible carbs, but provides a decent amount of fiber. Fiber promotes gut health and may reduce the risk of various diseases.
Proteins are the building blocks of the body, and are needed for both growth and maintenance.
Broccoli is relatively high in protein compared to most commonly consumed vegetables (29% of its dry weight).
However, because of the high water content of broccoli, a cup of broccoli only provides 3 grams of protein.
Bottom line: Broccoli is higher in protein than most vegetables. However, because of its high water content, the amount of protein in each serving is relatively low.
Vitamins and Minerals
Broccoli contains a variety of vitamins and minerals.
The most abundant ones are listed below.
- Vitamin C: An antioxidant, important for immune function and skin health (). Half a cup of raw broccoli (45 grams) provides almost 70% of the recommended daily intake.
- Vitamin K1: Broccoli contains high amounts of vitamin K1, which is important for blood clotting and may promote bone health (, ).
- Folate (B9): Particularly important for pregnant women (), folate is important for normal tissue growth and cell function ().
- Potassium: An essential mineral, beneficial for blood pressure control and preventing cardiovascular disease ().
- Manganese: This trace element is found in high amounts in whole grains, legumes, fruits and vegetables.
- Iron: An essential mineral, which has many important functions in the 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 contains a little bit of almost everything we need.
Bottom line: Broccoli is high in many vitamins and minerals. These include vitamin C, vitamin K, folate, potassium, manganese and iron.
Other Plant Compounds
Broccoli is rich in various antioxidants and plant compounds, which contribute to its health benefits.
- Sulforaphane: One of the most abundant and extensively studied plant compounds in broccoli. It can have protective effects against various types of cancer (, , ).
- Indole-3-carbinol: A unique nutrient found in cruciferous vegetables, which may have beneficial effects against 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. It may protect against heart disease, cancer, inflammation and allergy ().
- Quercetin: An antioxidant with numerous benefits, including lower blood pressure in people with high blood pressure ().
Bottom line: Broccoli is high in many plant compounds that have been associated with health benefits. The most abundant one is called sulforaphane.
Health Benefits of Broccoli
Cruciferous vegetables like broccoli contain sulfur-containing compounds that are responsible for their often spicy and bitter taste ().
These are bioactive compounds that may have numerous beneficial effects on health.
Cancer is characterized by the rapid growth of abnormal cells, beyond their normal boundaries, and is often linked to oxidative stress ().
Broccoli is loaded with compounds that are believed to have protective effects against cancer.
Observational studies suggest that consumption of cruciferous vegetables, including broccoli, is linked to reduced risk of many cancers. This includes lung, colorectal, breast, prostate, pancreatic and gastric cancer (, , , ).
The factor that sets cruciferous vegetables apart from other vegetables, is a unique family of plant compounds called isothiocyanates.
Isothiocyanates have been shown to affect liver enzymes, reduce oxidative stress, decrease inflammation, stimulate the immune system and decrease the development and growth of cancer (, , ).
The main isothiocyanate in broccoli is sulforaphane, which acts against formation of cancer at the molecular level, such as by reducing oxidative stress (, , ).
Sulforaphane is found in 20-100 times higher amounts in young broccoli sprouts than in full-grown broccoli heads ().
Broccoli supplements are also available in powder form, but supplemental intake may not contribute an equivalent amount of isothiocyanates, and thus may not give the same health benefits as eating whole broccoli (, ).
Bottom line: Broccoli contains a unique family of plant compounds called isothiocyanates, the most abundant of which is called sulforaphane. They improve many risk factors for disease, and may reduce the risk of cancer.
Lower Cholesterol Levels
Cholesterol has many important functions in the body.
For example, it is a key factor in the formation of bile acids, which are substances that help us digest fats.
Bile acids are formed in the liver, then stored in the gallbladder and released into the digestive system whenever we eat fat.
Afterwards, the bile acids are reabsorbed into the bloodstream and used again.
Substances in broccoli have the ability to bind with bile acids in the gut, increasing their excretion out of the body and preventing them from being reused ().
This results in the synthesis of new bile acids from cholesterol, reducing the total level of cholesterol in the body.
This effect has been linked to reduced risk of heart disease and cancer ().
According to one study, steamed broccoli is particularly effective for lowering cholesterol levels ().
Bottom line: Broccoli may lower cholesterol levels by binding to bile acids in the gut, causing them to be expelled from the body. This reduces total cholesterol in the body.
Impaired eyesight is a common consequence of aging.
Two of the main carotenoids in broccoli, lutein and zeaxanthin, have been associated with decreased risk of age-related eye disorders (, ).
Vitamin A deficiency may cause night blindness, which can be reversed with improved vitamin A status ().
Broccoli contains beta-carotene, which is converted into vitamin A in the body. It may therefore have beneficial effects on eyesight in individuals with a low vitamin A intake.
Bottom line: Broccoli contains several carotenoids. These are plant compounds that may improve eye health and reduce the risk of eye-related diseases.
Broccoli is usually well tolerated, and allergy is rare ().
Broccoli is considered a goitrogen, which means that high amounts may have harmful effects on the thyroid gland in sensitive individuals.
Cooking (high heat) can alleviate these effects ().
Individuals who are on the drug warfarin (blood thinner) should consult with a doctor before increasing their broccoli consumption, because the high amount of vitamin K may interact with the medication ().
Bottom line: Broccoli is usually well tolerated. It may have undesirable effects on the thyroid in some people, and those taking blood thinners should consult with a doctor before incorporating large amounts of broccoli into the diet.
Broccoli is one of the most popular vegetables in the world. It is easy to prepare, and can be eaten 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.
The consumption of broccoli has been linked with reduced risk of cancer and heart disease, as well as improved eye health.