With up to 90% of our bone strength established by around the age of 18, it’s essential that parents do all they can to help their children develop strong, healthy bones during the all-important development years.

As national interest in childhood nutrition booms and parents are becoming more focussed on encouraging healthy eating practices, it comes as a shock to find out that a study of 1,783 parents, carried out by www.raisingkids.co.uk , reveals while ‘healthy growth and development’ tops parents list of concerns for their children, many simply don’t know the facts about bone health.

Calcium and Vitamin D, as part of a healthy balanced diet and lifestyle, are essential nutrients for strong bones.

Calcium is especially important for growing children and young people, to help build healthy bones and teeth.

Adults also need plenty of calcium. If you have one glass of semi-skimmed milk, a small pot of low-fat fruit yoghurt and 40g of hard cheese, it will provide the approximate amount of calcium an adult needs in one day.

Although most parents understand that calcium is needed to add strength to bones and teeth, less than one in ten realise that vitamin D is important because it helps the body absorb calcium.

“While genetics play a big part in the development of strong bones, parents can help by ensuring their children have a healthy diet and lifestyle, with sufficient calcium and vitamin D, and weight-bearing exercise on a regular basis,” says dietician Penny Hunking.

There is also confusion as to how parents can make sure their children get enough of these two important bone nutrients.

While calcium is available in a wide range of foods, including soya beans, tofu, milk, cheese, green vegetables especially watercress and okra (but not spinach) and dried fruit, particularly dried figs, our main source of vitamin D is sunshine.

But with increasing concerns about safe sun exposure – especially with little ones – experts are concerned that we may need to top up our vitamin D supply through diet.

The richest source of this important nutrient is oil-rich fish such as salmon, mackerel and sardines, in eggs, some breakfast cereals and margarines.

Canned sardines, and other fish, where it is possible to eat the bones are good sources of calcium and vitamin D.

Another option when it comes to upping your intake of vitamin D is in foods that are fortified with the nutrient.

If you and your little ones aren’t getting enough vitamin D, there is a risk of the harmful effects of too much vitamin A (found in cheese and liver-rich food products, for example) which, over many years, will affect your bones and make them more likely to fracture when you’re older.

So if you're short on vitamin D, it might be a good idea to boost the amount you're getting by taking supplements.