What makes green foods so special?

We’ve all heard that greens are important for our health and diet. Ever wondered exactly what makes them good for us? We turn to doctors and dietitians to understand their power.

A diet high in green vegetables lowers the risk of high blood pressure, thereby reducing the chances of health problems such as heart attack and stroke. Image Source

On a recent evening, I sat with my family and feasted on slow-cooked lamb, pan-fried mushrooms and the sweetest honey-roast parsnips. I even ate some sprouts, not because I enjoy the flavour – I don’t – but because I want to embrace a healthy, balanced lifestyle, and to do that I must eat my greens.

But what is it about these little vegetables – and indeed all green produce – that makes them such a vital dietary component?

According to Fatima Sadek, a dietitian at Abu Dhabi’s Imperial College London Diabetes Centre, green foods are packed with goodness and innumerable health benefits.

“Leafy greens are full of vitamins, minerals and disease-fighting phytochemicals,” she says. “They are also rich in fibre, an important nutrient for weight loss, because you feel full for longer.”

The most nutritious greens include broccoli, cabbage, spinach and, you guessed it, Brussels sprouts. Love them or loathe them, few vegetables beyond this list offer more health benefits.

Health experts from Cleveland Clinic Abu Dhabi agree that eating greens has many advantages. Dr Yasir Akmal, general surgeon at the clinic’s Digestive Disease Institute, says: “Green vegetables are good for your digestive system as they are rich in dietary fibres, which help get rid of waste and gastric irritants. They also relieve constipation by promoting bowel movement.”

Dr Thomas Bartel, of the Heart & Vascular Institute at the clinic, adds that vegetables and legumes protect against strokes and coronary heart disease.

“Try to eat green leafy vegetables such as lettuce, spinach, broccoli and cabbage to lower your risk of cardiovascular disease,” he says. “Eating them raw has also been shown to lower blood pressure.”

The way we prepare our greens is important, too. Sadek recommends washing all fruit and vegetables in a vinegar solution to reduce our exposure to pesticides and bacteria by up to 98 per cent.

“You can easily make your own mixture at home,” she says. “In a bottle, mix three parts water to one part white vinegar. Spray onto the vegetables to remove the pesticide residue and then rinse with water.”

The next step is to choose a healthy cooking technique to reap full nutritional benefits. Don’t, for example, pull out the deep fryer. Likewise, unless you want to put your children off greens for life, avoid boiling your veggies to a pulp, and be aware that a food’s cooking method affects its nutritional value.

Heat can destroy up to 20 per cent of some vitamins, in particular vitamin C, folic acid and potassium, which is why some nutritionists swear by raw ingredients, believing that uncooked food retains all its nutrients and is therefore the healthiest option.

Conversely, heat can trigger the release of antioxidants, leading some experts to consider cooking a great benefit.

Steaming is arguably the healthiest option, with food retaining a much greater percentage of its nutritional make-up than boiling or microwaving.

“One major way to take control of the food you, your family and your guests eat is to cook at home,” says Sadek. “Often this means rediscovering the simple pleasures of preparing and cooking your own meals.

“Also, feedback suggests that if you plan your meals, you cut down on wastage because you shop smarter,” she says.

While countless experts extol the virtues of eating green vegetables, is it possible to consume too many?

In terms of weight gain, no, as most greens are only about 35 calories per serving. They can, however, temporarily discolour the skin, as large quantities of carotenoids – the vegetable’s pigmentation – can cause a harmless orange hue. Excessive consumption can also cause bloating and gas. If you’re experiencing either symptom, simply reduce your daily serving.

According to Health Canada, the Canadian government’s public health department, half a cup of broccoli or green beans or one cup of raw kale, spinach or lettuce are regarded as one helping. So, too, are half a cup of peas or cucumber or one medium stalk of celery.

Dr Bartel adds: “People who eat at least five servings of fruit and vegetables daily have a 28 per cent lower risk of cardiovascular disease than people eating fewer than 1.5 servings per day, and a 20 per cent lower risk of stroke compared to those who eat less than three servings per day.

“A diet high in green vegetables lowers the risk of high blood pressure, which can be attributed to severe health effects, including heart attack and stroke.”

On that note, I’m off to the supermarket to buy some Brussels sprouts, which will be steamed, of course.