winter wonder foods to keep you healthy

There are some foods we can eat this winter that will genuinely do us good. Two front runners – beetroot and broccoli – we can grow ourselves. Another two – pomegranates and blood oranges – are in supermarkets now, and they're all ideal cold-weather fare.

Broccoli in general is good for us. It is rich in the fibre and nutrients associated with all green veg, but it has another value. The florets are packed full with glucoraphanin, a compound used in the plant's defence system that is especially beneficial for our health. The only other vegetable it is found in is cauliflower. Eat broccoli and you are likely to reduce your chances of cardiovascular disease and certain cancers. With most varieties, you'll need to eat platefuls to derive the benefits, but now a newly bred form, Beneforté broccoli, contains more than twice the level of the good stuff.

From analysis of wild brassicas collected in Sicily, scientists at the John Innes Centre and the Institute of Food Research in Norwich found that these native forms had exceptionally high levels of glucosinolates, many times greater than their long-cultivated cousins. But the wild varieties are insubstantial, weedy things you'd hardly want to eat, so how are we to get the best of both worlds, a tender and tasty broccoli, with high levels of protective chemicals in every meal? That's Beneforté, the result of 30 years of research and crossbreeding cultivated broccolis with their wildflower ancestors. This new form has glucoraphanin levels high enough that eating only two portions a week will help protect against disease.

There are ongoing clinical trials taking place in Norwich with Beneforté broccoli. Earlier pilot studies have suggested that eating this type of broccoli can improve your metabolism and reduce the levels of LDL cholesterol in your blood, as well as slowing the progression of early-stage prostate cancer. Larger studies are now in progress to confirm these results.

Seeds and plants of Beneforté broccoli are not yet available, but they should be soon, so let's hope we'll be growing our own within the next couple of years. For now, we can buy it by the bag from some supermarkets.

juice the job

Interesting things have also recently emerged about the health benefits of beetroot. As well as containing calcium, magnesium, iron, phosphorous, potassium, manganese, folic acid and vitamin C, the natural dietary nitrates in beetroot – more specifically in beetroot juice – have been found to have two powerful physiological effects. They dilate (widen) the blood vessels, which can both reduce blood pressure and increase blood flow to muscles and the brain. In turn, this increases oxygen supply to the muscles for energy production which is especially beneficial during intensive exercise.

Team GB put the properties of beetroot to good use in the 2012 Olympics, with athletes supplied with small shots (7cl) of concentrated juice a day. Many international rugby teams also use it. However, besides sport, beetroot juice is expected to have widespread implications for the treatment of high blood pressure. Most currently available antihypertensive drugs work in just this way – dilating blood vessels and so decreasing the pressure within them. I know which I'd rather consume.

You can make your own beetroot juice, or buy James White Beet It or Cawston Press Brilliant Beetroot, or try the concentrated shots which have the great advantage of a controlled nitrate dose (0.4g), about the equivalent of 400ml juice. I like it straight, just as it is, but for the doubters, pre-dinner, add a shot of vodka and a splash of Tabasco and you'll have a delicious Crimson Mary. The beneficial nitrates are very soluble and easily lost in cooking, so either eat it raw (peel, grate and dress) or roast the roots, making sure that you do not waste the juice.

season's winners

This is also the season for pomegranates, ripe now all around the Mediterranean, and these are emerging as another natural wonder-food. Originally from Persia (Iran), the pomegranate is one of the oldest known fruits, long revered as super-healthy, but is there a scientific base for this claim?

Pomegranate juice is rich in potassium, Vitamin C, polyphenols and Vitamin B6. Clinical trials have shown it to reverse atherosclerosis – arterial disease from the formation of sticky plaques in our blood vessels – which leads to heart attacks and strokes.

Compounds called punicalagins, found only in pomegranates, lower cholesterol and blood pressure and increase the speed at which arterial blockages melt away. Half a cup a day – or the seeds of a fruit – is recommended for those with cardiovascular disease. Eat a couple of tablespoons of pomegranate for breakfast with yogurt, scattered with a few walnuts and a drizzle of honey and add them over the top of a winter salad.

Coming into season early in the new year is the final winter wonder-food, the blood orange. The red colouring comes mostly from anthocyanin pigments – important antioxidants – not usually found in citrus fruits. The same pigment gives blueberries their intense colour and antioxidant properties. Anthocyanins help to prevent cancer and decrease arterial disease, keeping blood vessels flexible and strong, so improving the outcome for those with cardiovascular illness. Peel and eat them as they are, drink their juice, or slice them into a salad with watercress and avocado.

Integrating these four foods into our diet seems to be not just delicious but a wise thing to do. And as with all produce, the fresher the better, so where possible, grow your own.