Broccoli packs a powerful health punch. Photo / 123rf
Broccoli packs a powerful health punch. Photo / 123rf
Broccoli boasts numerous benefits, from boosting our gut health to warding off dementia. Here’s how to eat more.
There is a humble vegetable lurking in all our fridges that packs a powerful health punch. From the earthy stems to the crunchy florets, from Tenderstem to purple-sprouting varieties, broccoli is full of vitamins, antioxidants and polyphenols that not only build up our heart and brain health but also may halt cancerous cells from taking hold.
Many of these attributes are a result of broccoli being a cruciferous vegetable, explains nutritionist Dominique Ludwig. “This means that it contains natural sulphur-containing bioactive plant compounds known as glucosinolates. This not only gives them a unique pungent aroma and slightly bitter flavour, but also has benefits for us when we eat them.”
Repeatedly, studies have found that broccoli is excellent for our hearts.
One recent paper found that participants who ate a soup made with broccoli and other cruciferous vegetables for lunch for a fortnight saw their blood pressure drop, in turn lowering their risk of a heart attack or stroke by 5%.
Studies have found that broccoli is excellent for our hearts. Photo / 123rf
An earlier study from Imperial College London found the sulforaphane in broccoli, which gives it its strong smell and bitter flavour, activated a protective protein in the arteries, reducing inflammation and lowering the risk of atherosclerosis (a build-up of fatty plaques in the arteries).
Broccoli also contains potassium, a mineral that can support cardiovascular health and can help manage blood pressure, and vitamin K, which regulates blood clotting and circulation, Ludwig notes.
2. Protects against prostate and colon cancer
Some studies have found men who ate a broccoli-rich diet (400g a week) had a lower risk of developing prostate cancer.
It is thought this effect is due to isothiocyanate, compounds created by the body as it breaks down broccoli. These have been shown to act as antioxidants; help rid the body of cancer-causing toxins; and interfere with pathways in the body that trigger inflammation.
A separate paper from Imperial College London found for every extra 260 micrograms of folate in a person’s diet each day — which is in broccoli and leafy greens — the risk of colon cancer fell by 7%.
Additional research has found mice fed a diet rich in indole-3-carbinol, which is produced when the body breaks down the glucosinolates in broccoli, were protected from gut inflammation and colon cancer. The scientists behind that study, from the Francis Crick Institute, concluded that, while we can’t protect against genetic factors that increase our risk of cancer, “we can probably mitigate these risks by adopting a diet with plenty of vegetables”.
3. Boosts brain power
Broccoli’s high folate content is thought to support the health of our brains. “Folate helps to lower levels of homocysteine (an amino acid) in our blood, which is beneficial for our cardiovascular health and therefore our long-term brain health,” Ludwig says.
The hit of iron that broccoli offers may also play a part in protecting our cognition (it contains 0.7mg per 100g). “Iron is necessary for our brain chemistry and neurotransmitter formation,” she says.
While there’s a lot of evidence that a diet rich in plant compounds, called flavanols, protects the brain, eating one particular flavanol found in broccoli called kaempferol has been linked to a 51% lower risk of dementia.
The sulforaphane in broccoli is thought to slow the progression of arthritis and maybe even prevent it. Lab studies involving mice show the compound blocks the inflammatory process in joints that fuels conditions and might slow cartilage damage in osteoarthritis.
A study in people who followed a diet high in broccoli experienced lower levels of pain caused by arthritis. Photo / 123rf
A separate study in people who followed a diet high in broccoli — the equivalent of three portions day in the form of a soup — experienced lower levels of pain caused by arthritis.
4. Protects eye health
Broccoli also works to protect our sight. “Broccoli contains carotenoids, antioxidants that protect the eye from oxidative damage,” Ludwig says.
This antioxidant is also thought to reduce the risk of developing cataracts, and slow the progression of the condition if it does occur, she says. Additionally, the body converts carotenoids into vitamin A, which is needed to produce pigments that are needed to see.
Vegetables are one of the richest sources of fibre, which is essential for a healthy gut.
Broccoli is a powerhouse in this regard as it contains both soluble and insoluble fibre. Soluble fibre absorbs water from the large bowel, making stools softer, while insoluble fibre stimulates the gut to release water and mucus to help stool move through the gut.
For every 80g portion, it contains 2g of the 30g of fibre we should be eating each day.
What’s more, different types of broccoli — whether standard, Tenderstem or purple sprouting varieties — each count as different plants, Ludwig notes. Including a diverse mix of vegetables, such as swapping between different broccoli varieties, can enhance the diversity of microbes in the gut, as well as overall health.
The different types of broccoli
Broccoli
Tenderstem (broccolini)
Purple sprouting broccoli
Broccoli sprouts
Standard broccoli — with a thick stem and lots of florets, technically called calabrese — and Tenderstem, which is also known as broccolini and is a hybrid of broccoli and Chinese kale, are the two most common types of broccoli sold in the UK.
Broccoli sprouts may top the list when it comes to health. Photo / 123rf
“Both have a similar nutrition profile,” Ludwig says, though some research suggests Tenderstem has slightly more folate, a vitamin that keeps red blood cells and the nervous system healthy, and carotenoids, an antioxidant that protects cells from damage.
The less popular purple sprouting broccoli may be even better for our health. “It contains the additional benefits of the purple plant compounds called anthocyanins,” Ludwig explains. Essentially, it lends a bigger antioxidant punch for each bite.
But broccoli sprouts (broccoli plants that are three to five days old and resemble cress) may top the list when it comes to health. “They have the highest amount of sulforaphane (a powerful antioxidant) than any other type of broccoli,” she says.
The healthiest ways to eat broccoli
Before you even get to eating broccoli, there are ways of upping its health benefits.
“When we chop broccoli we encourage the development of sulforaphane,” explains Ludwig. So, cutting the vegetable and leaving it for a short while is beneficial.
“This may not be very practical in everyday cooking, but can be great if chopped into a salad, for example,” she says. Eating broccoli raw as part of a salad, or crudités, also preserves more vitamin A, as well as folate.
When it comes to cooking broccoli, the goal is to preserve the water-soluble vitamins (those that dissolve in water) and plant compounds (such as polyphenols) as much as possible.
Steam, fry or boil: which way is best?
Steaming or stir-frying are the best ways to do this, as opposed to boiling. These cooking methods will also make it easier for the body to absorb the carotenoids within broccoli, Ludwig says.
“Cooking in too much water or for too long can lead to the greatest reductions in vitamin C — an 80g serving contains 63mg, over two thirds of our daily recommended amount of glucosinolates and folate,” she notes.
Steaming or stir-frying broccoli is the best way to get their health benefits. Photo / 123rf
Frozen broccoli should not be disregarded, however. “Since broccoli loses its nutrients over time, freezing can act like a time capsule, trapping the nutrients in place and preserving them for longer,” Ludwig notes. “While losses can still occur, the broccoli is usually frozen at peak ripeness when nutrients are at their highest.”
“The key is not to overcook your broccoli and to enjoy it al dente wherever possible,” she adds. “Broccoli not only loses nutrients as we cook it, but also it can become unappealing and soggy.”
Verdict: Is broccoli healthy?
“I try not to put any one food on a pedestal over others as the key to a healthy diet is diversity,” Ludwig says. “But broccoli is versatile, inexpensive and widely available and definitely has an important place in a healthy diet.”
While leafier green vegetables such as spinach, kale or chard technically beat broccoli in terms of nutrient density per bite, the special plant compounds all broccoli varieties contain means that the vegetable is excellent for our health.
