Diseases of Lifestyle

Diseases of lifestyle are defined as diseases that can potentially be prevented by changes in diet, lifestyle and environment.  These include Type 2 Diabetes; Obesity; Cardiovasuclar Disease and Stroke; and certain types of cancers.

The World Health Organisation (WHO) reported that diseases of lifestyle account for 36 million deaths each year: cardiovascular diseases – 17.3 million people; cancers – 7.6 million;  respiratory diseases – 4.2 million; and diabetes – 1.3 million; and they all have common risk factors: smoking; inappropriate diet and physical inactivity.

Diet and lifestyle are major factors thought to influence susceptibility to these diseases.  Even a modest weight loss of 5 – 10% of body weight, can improve blood pressure, fasting glucose levels, triglycerides and HDL cholesterol.   Studies have also shown that regular physical activity helps prevent obesity, heart disease, hypertension, diabetes and certain cancers. For example, 30 minutes of moderate physical activity each day, like a brisk walk, can reduce your risk of a heart attack by up to 50%.

Diabetes

Diabetes is a condition, in which there are high blood sugar (glucose) levels because your body may produce none, or not enough of a hormone called insulin, or your body does not respond properly to the insulin you produce.

Insulin is a hormone that helps the body to use the energy from sugar, starch and other types of food.   Without energy the body cannot function properly.   Glucose is a sugar which provides the main source of energy in the body.  If there is no or not enough insulin the body glucose level rises.  A normal glucose level for a non diabetic person is between 4 – 8 mmol/L and does not go higher than this even after eating.

There are two types of diabetes:

  • Type 1 (insulin dependent):  this is when the body has a severe lack of its own insulin.  It usually develops early in life and is the most common type of diabetes in children.  Type 1 diabetes is treated with insulin injections.  .
  • Type 2 (non-insulin dependent):  usually develops later on in life and appears to have contributing factors including genetic factors, age and weight.  Although the body producers insulin, the insulin produced is not enough or does not work properly.  It can be treated by diet and physical activity alone, or combining these with tablets.  In some people the disease may progress and insulin treatment may be required later in life.

 

Gestational diabetes: affects women during pregnancy and may lead to Type 2 diabetes later on in life.

Eating healthily is an important part of treatment for diabetes.  No matter how your diabetes is controlled, healthy eating will help to control your blood glucose levels and reduce the risk of developing other illnesses such as heart disease.

Impaired glucose tolerance (IGT):  an intermediate condition in the transition between normality and diabetes.  People with this are at risk of progressing to Type 2 diabetes although this is not inevitable.

Cardiovascular Disease

Cardiovascular disease is a group of disorders of the heart and blood vessels and they include:

  • coronary heart disease – disease of the blood vessels supplying the heart muscle;
  • cerebrovascular disease – disease of the blood vessels supplying the brain;
  • peripheral arterial disease – disease of blood vessels supplying the arms and legs;
  • rheumatic heart disease – damage to the heart muscle and heart valves from rheumatic fever, caused by streptococcal bacteria;
  • congenital heart disease – malformations of heart structure existing at birth;
  • deep vein thrombosis and pulmonary embolism – blood clots in the leg veins, which can dislodge and move to the heart and lungs.


Risk factors for cardiovascular disease

The WHO reports that the most important behavioural risk factors of heart disease and stroke are unhealthy diet, physical inactivity, smoking and harmful use of alcohol. Behavioural risk factors are responsible for about 80% of coronary heart disease and cerebrovascular disease.  The effects of unhealthy diet and physical inactivity may show up in individuals as raised blood pressure, raised blood glucose, raised blood lipids, and overweight and obesity. These “intermediate risks factors” can indicate an increased risk of developing a heart attack, stroke, heart failure and other complications.

Lifestyle Cancers

We have all heard it, prevention is better than cure!  The WHO reports that approximately 30% of cancer deaths are due to the five leading behavioural and dietary risks:

  • high body mass index – a BMI over 25
  • low fruit and vegetable intake – Increasing your fruit and vegetable consumption can reduce your risk of colon cancer by up to 50%.
  • lack of physical activity
  • smoking
  • alcohol consumption

 

and that 40% of cancers can be attributed to lifestyle factors.  This is an indicator that in some incidences, cancer can be a preventable disease and swapping some bad habits for healthier ones can help reduce the risk of developing the disease.

Strength of evidence for an increased risk of cancer in relation to dietary factors and alcohol. (Cancer Research UK)

Factor Sufficient Probable
Alcohol Bowel, breast, larynx, liver, oesopagus, oral cavity, pharynx
Fat Breast
Fibre Bowel
Fruit and vegetables Larynx, lung, oesophagus, oral cavity, pharynx, stomach
Milk Bowel
Processed and red meat Bowel
Salt Stomach
* Red denotes increased risk and blue denotes reduced risk