Making lifestyle changes is the most effective way to prevent having a heart attack (or having another heart attack). There are 3 main steps you can take to help prevent a heart attack (as well as stroke):

• eat a healthy, balanced diet
• do not smoke
• try to keep your blood pressure at a healthy level

A healthy diet

Eating an unhealthy diet that is high in fat will make hardening of the arteries (atherosclerosis) worse and increase your risk of a heart attack.

Continuing to eat high-fat foods will cause more fatty plaques to build up in your arteries. This is because fatty foods contain an unhealthy type of cholesterol.

There are 2 main types of cholesterol:

• low-density lipoprotein (LDL) – this is mostly made up of fat plus a small amount of protein; this type of cholesterol can block your arteries, so it is often known as "bad cholesterol"
• high-density lipoprotein (HDL) – this is mostly made up of protein plus a small amount of fat; this type of cholesterol can reduce deposits in your arteries, so is often known as "good cholesterol"

There are also 2 types of fat – saturated and unsaturated. Avoid foods containing high levels of saturated fat, as they increase levels of LDL cholesterol in your blood.

Foods high in saturated fat include:

• pies
• fried foods
• sausages and fatty cuts of meat
• butter
• ghee (a type of butter often used in Indian cooking)
• lard
• cream
• hard cheese
• cakes and biscuits
• foods that contain coconut or palm oil

You should aim to follow a Mediterranean-style diet. This means eating more bread, fruit, vegetables and fish, and less meat.

Replace butter and cheese with products based on vegetable and plant oil, such as olive oil. Oily fish, such as herring, sardines and salmon, can form part of a Mediterranean-style diet, but there's no need to eat this type of fish specifically to try to prevent another heart attack.

Also, taking omega-3 fatty acid supplements, or eating foods fortified with omega-3 fatty acids, has not been found to help prevent another heart attack.

Never take a food supplement without first consulting a GP. Some supplements, such as beta-carotene, are potentially harmful.

Smoking

Smoking is a major risk factor for heart attack because it causes atherosclerosis and raises blood pressure.

A GP can refer you to a local NHS Stop Smoking Service, which will provide support and advice about the best ways to quit.

If you are committed to quitting but do not want to be referred to a stop smoking service, a GP should be able to prescribe treatment to help with withdrawal symptoms you may experience.

High blood pressure

Persistent high blood pressure (hypertension) can put extra strain on your arteries and heart, increasing your risk of a heart attack.

High blood pressure can often be reduced by eating a healthy diet, moderating your alcohol intake, maintaining a healthy weight and doing regular exercise.

Diet and high blood pressure

The advice on eating a healthy, balanced diet also applies if you have high blood pressure. In addition, cut down on the amount of salt in your food.

Salt raises blood pressure. The more salt you eat, the higher your blood pressure. You should aim to eat less than 6g of salt a day (2.4g sodium) – that's around 1 teaspoonful.

Eating a low-fat diet that includes lots of fibre – such as wholegrain rice, bread, pasta and plenty of fruit and vegetables – has been proven to help lower blood pressure. Fruit and vegetables also contain vital vitamins and minerals and help keep your body healthy.

You should aim to eat 5 portions of fruit and vegetables every day.

Alcohol

If you drink alcohol, do not exceed the recommended limits:

• men and women are advised not to regularly drink more than 14 units of alcohol a week
• spread your drinking over 3 or more days if you regularly drink as much as 14 units a week

14 units is equivalent to 6 pints of average-strength beer, or 10 small glasses of low-strength wine.

Regularly exceeding the recommended alcohol limits raises your blood pressure and cholesterol level, increasing your risk of a heart attack. Avoid binge drinking, which is drinking lots of alcohol in a short space of time or drinking to get drunk.

Binge drinking can cause a sudden and large rise in your blood pressure, which could be potentially dangerous.

Research has found people who have had a heart attack and continue to binge drink are twice as likely to die from a serious health condition, such as another heart attack or stroke, compared with people who moderate their drinking after having a heart attack.

Contact your GP if you find it difficult to moderate your drinking. Counselling services and medicines can help you reduce your alcohol intake.

Weight

Being overweight forces your heart to work harder to pump blood around your body, which can raise your blood pressure. Use the BMI healthy weight calculator to find out if you are a healthy weight for your height.

If you do need to lose weight, remember that losing just a few kilos will make a positive difference to your blood pressure and health.

Exercise

Being active and doing regular exercise will lower your blood pressure by keeping your heart and blood vessels in good condition. Regular exercise can also help you lose weight, which will help to lower your blood pressure.

Low-impact activities such as walking, swimming and cycling are recommended. More strenuous activities, such as playing football and squash, may not be suitable for you. Check with the doctor in charge of your care.

Find out more about the benefits of walking, swimming for fitness and how to start cycling.