The following correction was printed in the Guardian's Corrections and clarifications column, Monday 8 June 2009
The article below got the formula backwards for calculating where you fall on the body mass index. We should have said: multiply your height by itself (in metres). Take your weight (in kilograms), and divide it by the height figure you worked out. Anything between 18 and 25 is deemed a healthy outcome.
What's the best way to protect ourselves from ill health as we get older? While there's nothing we can do about some factors - such as the genes we inherit from our parents - there are steps we can take to minimise the risk of a painful and disabled old age. We take a look at five age-related ailments and diseases and explain how to cut the chances of them developing. As you will see, many of the same preventative strategies - not smoking, eating and drinking healthily, exercising and watching your weight - offer protection against a range of serious health conditions.
Cancer
Research now shows that half of all cancers could be prevented by lifestyle changes.
Stop smoking: It not only causes lung cancer but also increases the risk of mouth, stomach and cervical cancer. Pipes, cigars, roll-ups and low-tar cigarettes are no healthier as alternatives. Second-hand smoke is a risk factor, too: avoid living in a smoky atmosphere.
Drink less alcohol: It's a risk factor for seven cancers and a recent study showed than even a daily glass of wine increases a woman's chance of breast cancer. The less you drink, the lower the risk: a maximum two units a day for women and three to four units for men is recommended by Cancer Research UK. A unit is half a standard (175ml) glass of wine, a half pint of standard beer or one measure of spirits.
Eat a healthy diet: It should include five daily portions of fruit and vegetables (thought to cut the risk of several types of cancer), plenty of wholegrain bread and cereals (cuts the risk of bowel cancer), and only a small amount of saturated fat (linked to breast cancer). Eat less red and processed meat (a risk factor for bowel and possibly stomach cancer) and cut down on preserved foods high in salt (they could increase stomach cancer risk). Steer clear of vitamin supplements: recent research has shown they don't protect against disease.
Maintain a healthy weight: It can reduce cancer risk. You can find out if your weight is healthy for your height using the body mass index (BMI): multiply your height by itself (in metres) and then divide by your weight (in kilograms). Anything between 18 and 25 is healthy.
Exercise regularly: It's thought to reduce the risk of bowel and breast cancer. Just 30 minutes of moderate activity a day, at least five days a week, is enough. Any exercise will do, as long as it makes you slightly warm and out of breath. Split it up into 10-minute sessions if it suits you.
Take care in the sun to reduce the risk of skin cancer. Stay in the shade between 11 and 3, or cover up; in the sun, use sunglasses with standard UV protection, a wide-brimmed hat and a broad spectrum sunscreen (which protects against both UVA and UVB rays) with an SPF of at least 15; apply liberally and often. Avoid sunbeds - they're no safer.
Take part in the national screening programmes for breast and bowel cancer (the last is still being rolled out). Screening may detect pre-cancerous changes as well as early-stage cancer. What age you'll be offered it depends on where you live in the UK, but when you're eligible you should receive an invitation.
Talk to your GP if you're worried about a family history of cancer. You may qualify for special screening and referral to a genetics centre.
If you're a woman, bear in mind that HRT increases the risk of breast cancer, as does the contraceptive pill (although the risk returns to normal ten years after you stop using the pill). Having children, especially early on in life, reduces the risk of breast cancer, as does breastfeeding; the longer you breastfeed the greater the protection.
More information on breast, bowel and skin cancer
Cardiovascular disease
The best way to reduce this group of illnesses is to reduce or prevent the build-up of clumps of fat in the arteries (known as atherosclerosis). They can result in dangerous blockages which cause heart attacks and strokes.
Stop smoking: It damages the arteries, and quitting is the single best thing you can do to reduce your risk.
Exercise regularly: It will lower the risk of heart disease and stroke.
Maintain a healthy weight: If you're very overweight, a structured weight loss programme of diet and exercise, with support from a health professional, could help you lose about 5-10% of your body weight within six months - enough to reduce your chance of getting heart disease. In particular, keep your waist measurement in check: 94cm and above for men and 80cm and above for women is a health risk.
Eat a healthy diet: There's some evidence that oily fish (such as herring, mackerel, salmon and pilchards) protects against heart disease. Eat two-three portions of fish per week, at least one of which should be oily. Cut down on salt to a maximum of 6g a day, and less for children.
Drink alcohol in moderation: One or two units a day is thought to protect the heart in men over 40 and women after menopause. But excess alcohol raises the risk of heart problems.
Manage stress: There's no evidence that stress is a direct risk factor, but it may contribute in some way. Learn some techniques to help you relax.
If you're over 40, have your risk factors assessed by your GP. He or she will calculate your chance of developing cardiovascular disease over the next ten years. If you're at high risk, you'll be advised to make lifestyle changes and have drug treatment.
More information on heart attacks and stroke
Memory loss and dementia
There's no sure way you can prevent dementia but regular exercise and a healthy diet, with plenty of fruit and vegetables and limited fat and salt intake, can help keep the brain healthy.
Stop smoking: It has a harmful effect on blood vessels in the brain.
Keep your mind active: Research has found that reading, playing board games, playing a musical instrument and dancing are all linked to a reduced risk.
Stay involved socially, whether through work, community activities, voluntary work, or religious groups.
Make sure you get enough vitamin D (mainly through sunshine): Although it's not yet proven, some recent evidence from Manchester University has linked low levels of vitamin D to cognitive problems.
Get your blood pressure and cholesterol checked regularly: They are both risk factors for dementia.
Drink alcohol in moderation: Some research has suggested that moderate amounts of red wine may help to protect the brain against dementia.
Osteoarthritis
Two in every 10 people over 60 suffer from this painful joint disease that affects the hips, knees, spine and hands. It usually comes on gradually, so at the first sign, you can take steps to keep it at bay.
Maintain a healthy weight: Probably the single most important thing you can do, as extra weight puts a strain on the knee and hip joints.
Exercise regularly: It protects joints by keeping the muscles strong. If you're not sure what type of exercise you need, get referred to a physiotherapist
Look after your joints: Protect them from sports-related injuries and repeated minor injuries. Repeated kneeling and squatting can put stress on the joints.
Don't overdo things if you already have some pain from arthritis.
More information on osteoarthritis
Diabetes
Diabetes, caused by too much glucose in the blood, can lead to serious health problems like heart disease, stroke, nerve damage, eye and foot problems.
Lose weight if you are overweight or obese. You may need to consider taking medication in conjunction with lifestyle changes. In particular, keep your waist measurement in check (see cardiovascular disease, above).
Exercise regularly
Give up smoking
Drink alcohol in moderation
Have your blood pressure and cholesterol levels checked regularly
More information on type 2 diabetes
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