WHICH VEGETABLES ARE GOOD FOR YOU?

It's the time of the year when I start to think about my allotment and begin to thumb through the seed catalogues to decide which vegetables I will grow in the spring, for a summer harvest. Well, what are the healthiest vegetables to grow? I know that all vegetables are good for you, but according to the Nutrient Rich Foods index, some are even healthier than others.

So what decides what you grow in your garden or allotment? It may be what tastes best, or it may just be just what grows with the least effort; it's certainly hard to resist the sheer bounteousness of courgettes, even if they're not my favourite vegetable. We are still eating our way through a freezer full of last summers homemade courgette fritters and courgette soup! It's a running joke with our grandson, that almost everything we eat contains courgette in some form.     

Another consideration, especially at this health-conscious time of year, is nutrition. Plants differ in their ability to deliver the essential nutrients needed for a healthy diet. A recent paper in the Journal of the Academy of Nutrition and Dietetics looked at this question, using the Nutrient Rich Foods (NRF) index. For each food, the NRF index adds up all the per cent daily values (per serving) for nine “good” nutrients, then subtracts the sum of per cent daily values for three “bad” nutrients that we eat too much of. “Daily values” are worked out by the US Food and Drug Administration, but are similar to Britain’s “guideline daily amounts”. The nine good nutrients are protein, fibre, vitamins A, C and E, calcium, magnesium, potassium and iron, while the three bad guys are the usual suspects: saturated fat, sugar and salt. The more of the former and the less of the latter, the higher a food scores.

But that’s enough of the complex nature of nutrients - if we look just at vegetables, very near the top are “dark green” varieties of all kinds, including leafy salads, chard, cabbage and broccoli. The king of healthy veg, an excellent source of nearly everything, is spinach. My wife has just made up some butternut, mushroom and spinach pies. They are delicious and good for us. So, if maximising healthy nutrients per square yard is your aim, then salads leaves, cabbage, spinach and broccoli are the things that should fill your veg plot.

Next come squashes, pumpkins and carrots, closely followed by a large group of “other vegetables” (including asparagus, beetroot, cauliflower, green beans, iceberg lettuce, courgettes, onions and turnips); all good for you, but not quite up there with cabbage. All these vegetables are slightly better for you raw than cooked, largely owing to the loss of vitamins and minerals on cooking.

Next come potatoes, although here there’s a lot of variation in how you choose to eat them; baked or boiled, sadly, is much better for you than chips. And don’t forget certain potato varieties are better for mashing or roasting than others. We swear by Maris Piper as a good all round cooking potato. However, sweet potatoes have the highest NRF index of all, above even leafy vegetables; sweet potatoes are a particularly good source of vitamins and also of potassium, which can help to lower your blood pressure. Incidentally, the definitive answer to whether potatoes count as one of your five a day is no, but sweet potatoes do. It’s just a pity that, despite new hardier cultivars becoming available, sweet potatoes are still not all that easy to grow in Britain.

But don’t get too carried away by differences between individual vegetables. If we take a step back and look at the bigger picture, all fruit and veg have high NRF scores. Dry beans, pulses, nuts and seeds have similarly high scores. Both outscore meat, which, though it has plenty of nutrients, is let down by lack of fibre and high levels of saturated fat. A bit below meat come eggs, then dairy products and grains, and finally (with negative nutrient scores) pure processed things such as sugar and fats. In short, compared with all the other foods you could be eating, any fruit and veg is a healthy option, and, of course, growing them is in itself good for you. This reminds me, I have to get down to the allotment and get the soil turned over before the frost and snow arrives to help break down the clay filled sod.