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Washing your hands with soap and water is a good way to prevent infections. (Dreamstime/TNS)

Top 10 deadliest diseases in the world – some are surprisingly preventable

People probably think of fast-acting, incurable diseases when they think of the deadliest diseases in the world. In fact, many of these types of diseases don’t even rank among the top 10 causes of death worldwide.

Several of the deadliest diseases are partially preventable, which is even more surprising. While a person’s location, access to preventive care and the quality of healthcare are non-preventable factors, there are others that can be changed to reduce one’s risk of these diseases.

1. Coronary artery disease

Coronary artery disease (CAD) is the world’s deadliest disease. Heart disease caused by narrowed blood vessels is also known as ischaemic heart disease. Heart failure, arrhythmias and chest pain can result from untreated CAD.

As life expectancy increases, socioeconomic changes occur and lifestyle risks increase, CAD death rates are rising in many developing nations.

Risk factors for CAD include:

  • Family history of CAD
  • Diabetes
  • Being overweight
  • High blood pressure
  • High cholesterol
  • Smoking.

By maintaining good heart health and taking medications when needed, you can prevent CAD. To reduce your risk, you can take the following steps:

  • Exercise regularly
  • Maintain a healthy weight
  • Avoid smoking
  • Drink only in moderation
  • Eat a balanced diet that’s low in sodium and high in fruits and vegetables.

2. Stroke

A stroke occurs when an artery in the brain is blocked or leaks. Within minutes of a stroke, oxygen-deprived brain cells will begin to die. A stroke causes sudden numbness and confusion, as well as difficulty walking and seeing.

Strokes can cause long-term disability if left untreated, and are among the leading causes of such disability. However, they are less likely to result in disabilities when treated within three hours.

According to the US Centers for Disease Control and Prevention (CDC), of people are aware that sudden numbness on one side is a symptom of stroke. However, only 38% know all the symptoms of stroke that should prompt them to seek emergency care.

Risk factors for stroke include:

  • Being female
  • Smoking, especially when combined with oral contraceptives
  • High blood pressure
  • Family history of stroke.

Preventative care, medications and lifestyle changes can reduce some of these risk factors. Strokes are more likely to occur if you smoke or drink excessively, so avoid those. High blood pressure can be controlled with medications or surgery as a stroke prevention method.

Overall, your risk of a stroke can be reduced by maintaining good health habits, including regular exercise and a balanced diet.

3. Chronic obstructive pulmonary disease

In chronic obstructive pulmonary disease (COPD), breathing becomes difficult over time. COPD includes chronic bronchitis and emphysema. In 2004, about 64 million people around the world were living with COPD.

Risk factors for COPD include:

  • Family history, with the AATD gene being linked to COPD
  • History of respiratory infections as a child
  • Smoking or secondhand smoke exposure
  • Lung irritants like chemical fumes.

Medications can slow the progression of COPD, but it can’t be cured. Stopping smoking and avoiding secondhand smoke and other lung irritants are the best ways to prevent COPD.

4. Lower respiratory tract infections

You can get a lower respiratory tract infection due to the flu, pneumonia, tuberculosis or bronchitis. Lower respiratory tract infections are usually a result of viruses, but bacteria can also cause them.

Symptoms of such an infection include coughing, breathlessness, wheezing and tightness in the chest. Breathing failure and death can result from untreated lower respiratory tract infections.

Risk factors for lower respiratory tract infections include:

  • A weak immune system
  • Crowded childcare settings, which mainly affects infants
  • Asthma
  • HIV (human immunodeficiency virus)
  • Influenza
  • Poor air quality or frequent exposure to lung irritants
  • Smoking.

Getting the flu shot every year is the best way to prevent lower respiratory tract infections. Regularly wash your hands with soap and water to avoid transmitting germs, especially before eating and touching your face. Rest at home until you feel better if you have a respiratory infection, as rest improves healing.

5. Diabetes

Diabetic complications are more likely to kill people in low- and middle-income countries. Although diabetes cannot always be prevented, you can manage the severity of your symptoms by exercising regularly and maintaining a healthy diet. In particular, eating more fibre helps with controlling your blood sugar.

Eating plenty of fruits and vegetables is one way to reduce your risk of many of these deadly diseases. — dpa

6. Respiratory cancers

Cancers of the trachea, larynx, bronchus and lungs are classified as respiratory cancers. Smoking, secondhand smoke and environmental toxins are the main causes. Pollution from household sources, such as fuels and mould, also contributes to the problem.

Approximately four million people die each year from respiratory cancer, according to a 2015 study in the European Review for Medical and Pharmacological Sciences. Due to pollution and smoking, researchers estimate that respiratory cancers will increase by 81% to 100% in developing countries.

This is especially as coal is still used for cooking in many Asian countries, especially in India. Lung cancer deaths caused by solid fuel emissions affect 17% of men and 22% of women.

7. Dehydration from diarrhoea

Diarrhoea occurs when you pass three or more loose stools in a day. When diarrhoea lasts for more than a few days, your body loses too much salt and water. Dehydration can result in death.

The most common cause of diarrhoea is an intestinal virus or bacteria transmitted by contaminated water or food. This is particularly prevalent in developing nations with poor sanitary conditions.

In children under five years of age, diarrhoea is the second leading cause of death. Each year, approximately 760,000 children die from diarrhoea.

The incidence of diarrhoea can be reduced by 40% with good handwashing techniques. It is also possible to prevent diarrhoea by improving sanitisation and water quality, as well as by providing access to early medical intervention.

8. Alzheimer’s disease and other dementias

It is estimated that 60% to 80% of dementia cases are caused by Alzheimer’s disease. In the beginning, the disease causes mild memory problems, difficulty recalling information and lapses in recollection.

As the disease progresses, you may lose memory of long periods of time. Alzheimer’s disease cannot currently be prevented.

There is no clear explanation for why some people develop it while others do not. Researchers are trying to understand this, as well as to find ways to prevent it. A heart-healthy diet may help reduce your risk of the disease. Such a diet is rich in fruits and vegetables, low in saturated fats from meat and dairy, and high in sources of good fats such as nuts, olive oil and lean fish.

9. Tuberculosis

Mycobacterium tuberculosis is the bacteria that causes tuberculosis (TB). Although some strains are resistant to conventional treatments, it is generally a treatable infection. HIV-positive people are more likely to die from TB, with 35% of HIV patients dying from TB.

The Bacillus Calmette-Guerin (BCG) vaccine is commonly used to protect young children against TB. To reduce the likelihood of developing TB, you can take a prophylactic, or preventive, medication if you believe you have been exposed to TB bacteria.

10. Cirrhosis

Cirrhosis results from chronic or long-term scarring and damage to the liver. Damage can be caused by kidney disease, hepatitis or chronic alcoholism. Your liver filters harmful substances from your blood and sends healthy blood throughout your body.

When these harmful substances affect the liver, scar tissue forms. The formation of scar tissue causes the liver to work harder in order to function properly. Ultimately, this may cause liver failure.

Cirrhosis can be prevented by avoiding behaviours that can damage the liver. A long-term drinker’s risk of developing cirrhosis increases with alcohol abuse, so avoiding alcohol can prevent damage.

By eating a healthy diet rich in fruits and vegetables, and low in sugar and fat, you can prevent non-alcoholic fatty liver disease. Last but not least, avoiding sharing anything that could have traces of blood and using protection during sex can decrease your risk of contracting viral hepatitis. Needles, razors and toothbrushes, among others, fall into this category.


The best way to reduce your risk of any of these conditions is to live a healthy lifestyle with good nutrition and exercise. Additionally, the consumption of alcohol in moderation and the avoidance of tobacco usage can be helpful.

Proper handwashing can prevent or reduce your risk of bacterial and viral infections.

By Datuk Dr Nor Ashikin Mokhtar
Published in Star Newspaper, 31 Oct 2022

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