Of course, cancer is not the only critical illness but it's forms vary widely from those which are considered virtually always curable to the more serious ones where the prognosis is poor. Advances in prevention and treatment of the disease are happening all the time and a survey from one of the major insurers shows that claims for critical illness are rising considerably.

Once you have a mortgage and people who depend on you, you normally have life insurance. This will give security to the family in the event of your death, but won't be any help at all if you're diagnosed with a serious illness. Very many more people are likely to survive illnesses which were formerly death sentences. Some types of leukemia, for example, respond well to treatment but this can be spread over anything up to 18 months and a lot of that time will be spent in hospital, returning home for brief spells between treatments. Obviously it would be impossible to continue with your job and even after recovery from a serious illness, you could have to change the type of job you're able to do.

Many advisers consider that critical illness cover is essential and should be seriously considered. As people are living longer, the likelihood of one of the serious illnesses occurring is higher. If you were to be diagnosed with one of the conditions covered by the policy you'd receive a lump sum which would be free of tax. This would be yours to spend as you wish. You would be able to continue paying the mortgage or to pay it off and the money could replace the wages you'd normally earn or it could be spent on adapting your home if necessary.

When it comes to which illnesses are covered, it varies from insurer to insurer and it's really important to check the various policies and see just what they cover. Not all cancers are included and referring back to the skin cancer mentioned earlier, so insurers don't include this unless it's reached the invasive stage. Some insurers offer cover against Alzheimer's disease but only if it's diagnosed by the age of 60, where others offer cover until 65. In some cases, if there's a family history of certain diseases, the premium will be increased. Certainly the younger and fitter you are, the cheaper the cover will be.

When you apply for critical illness cover, you'll be asked to fill in a questionnaire showing details of your personal details, general health and life style. Be sure to be completely accurate when doing this - rack your brains and mention any illness which you've suffered from and answer questions about family history as accurately as you can. If you later make a claim, the insurer will check the information you've given and if there are any inaccuracies, your claim could be in jeopardy.

Even if you haven't got children who rely on you, if you fall ill and couldn't rely on a partner to support you financially you could find yourself struggling financially. Critical illness cover should be seriously considered.