If you've never tried it, now's the time to consider this simple bean as a boon to your health, says Dr Wynnie Chan

The soya bean has been an important ingredient in Chinese cooking for thousands of years, yet its role in protecting us against osteoporosis, heart disease, breast cancer and other cancers has been the subject of research only in the last decade.

Some studies have suggested that plant oestrogens, in particular isoflavones (oestrogens similar in structure to the female oestrogen hormone called oestradiol) found in soya, may have the same effect as female oestrogens and help alleviate some symptoms of menopause including fractures, osteoporosis, hot flushes, aching joints and depression.

A study published in the journal Obstetrics and Gynaecology looked at the dietary intake of isoflavones among 478 post-menopausal Japanese women. The findings suggest that a diet rich in soya may help women retain stronger bones after menopause, thus reducing their risk of osteoporosis, a condition where bones become weak and brittle and may break. Women are much more vulnerable to osteoporosis than men because our levels of oestrogen, the hormone that helps bones stay strong, decrease substantially at menopause at the same time the rate of bone and calcium losses increases.

In this study, women in early and late stages of menopause who consumed the highest amount of isoflavones in foods from tofu, boiled soyabeans and soya milk had significantly thicker bones than those who consumed the lowest levels of isoflavones. In addition, women who consumed the largest amount of isoflavones in an early post-menopausal stage had significantly fewer backaches and aching joints. Isoflavones did not have an effect on menopausal symptoms in late stages of menopause.

Although this research does suggest that high intakes of soya products are associated with an increase in bone density in post-menopausal women, there is scientific evidence that our bones will benefit and increase in mass from adequate calcium in the diet, particularly during childhood and adolescence. In addition, regular weight-bearing exercises like jogging and brisk walking will slow down the rate at which calcium in the bones is lost.

Tips for increasing soy in your diet

• Replace fruit juice at breakfast with a glass of sweetened soya milk.
• Top your bowl of muesli with a pot of soy yoghurt instead of milk.
• Make your own sandwich spread with tofu (combine in a blender 250g tofu, 70g onion, 60g celery, 20g soya sauce, 1 tsp paprika, 5g coriander and 130g reduced fat mayonnaise).
• Eat Burgen bread (containing soya and linseeds) instead of your normal wholemeal or white bread.
• Make tofu burgers (mix 350g tofu, 75g rolled oats, 45g grated carrots, 90g chopped onion, 1 tsp chopped coriander, 1 chopped red chilli, 20g soy sauce and 1 egg. Then, shape into 8 burgers, coat with breadcrumbs, and bake at 180C/350F/gas mark 4 for 20 minutes or shallow fry for 10-15 minutes.
• Serve tofu satay with peanut dip as a starter or appetiser (drain a packet of firm tofu on kitchen paper for one hour to remove excess water, then cut into 2-inch cubes. Thread each cube onto a bamboo stick, grill on a high heat for 3 minutes on each side. Serve with satay sauce of peanut dip (blend together 8 tbsp peanut butter, 8tbsp water, 4tbsp cider vinegar, 2 tbsp soya sauce and 2 tbsp brown sugar).
• Use tofu dressing instead of your normal salad dressing (mash up: pack soft tofu with 1 tbsp sugar, 1 tsp salt, 1 tsp soya sauce, 1 tbsp rice wine vinegar or cider vinegar).
• Add soya beans to stews, casseroles or soups. Because they contain very little carbohydrates, dried soya beans need a long time to cook and prepare. Soak them for 5-8 hours, then boil rapidly for an hour and simmer for another 3-4 hours.
• Stir-fry tofu, vegetables and noodles for a quick supper (eg: a packet of boiled egg noodles with chunks of tofu, one tbsp vegetable oil, a couple of handfuls of beansprouts, 1 shredded carrot and 1 thinly sliced green pepper. Then add 2 tbsp soya sauce and1 tsp sesame oil. Cook for about 5 minutes, then sprinkle over 1 tbsp toasted sesame seeds, 2 tbsp toasted cashew nuts and 1 tbsp chopped spring onion before serving.
• Add sprouted soya beans to salads for extra crunch.