What are risk factors?

The factors in the body that trigger the probability of suffering from a disease are referred to as risk factors. For example, an excessive increase in an individual's body weight can trigger the chances of getting heart disease. Similarly, if an individual is exposed to carcinogenic substances, it increases the probability of suffering from cancer. These factors can pose a severe threat to the overall health of an individual.

Can exposure to risk factors be controlled?

Exposure to risk factors can be controlled to some extent but not completely. Also, not all risk factors can be controlled. Risk factors are specific sets of nucleotide sequences present in the genetic material of an individual. Once activated, they can increase the probability of an individual to suffer from a disease. The individual cannot control his exposure to the risk factors inherited from his parents. On the other hand, many risk factors can also be controlled by avoiding the conditions/substances that increase the risk of getting a disease. For example, a person can limit tobacco use to prevent cancer or maintain a proper diet to prevent obesity.

Modification or treatment of risk factors

People can modify many risk factors to decrease the probability of suffering from abnormalities in the body. They can treat high blood pressure and high cholesterol levels that can cause coronary heart diseases.

Categories of risk factors

Risk factors have been categorized into three groups:

Fixed risk factors

Risk factors can be changed or modified to decrease the risk of suffering from diseases. An individual's age can also be a risk factor, and it cannot be avoided in any way. Certain genes that exist in an individual's family history can increase the risk of getting a disease. They are also called fixed markers.

Variable risk factors

When certain interventions can alter a disease-causing determinant, it is called a variable risk factor. If an individual's alteration in the factor does not confer any change in the risk of the disease, the determinant is called a variable marker.

Causal risk factors

The disease-causing determinants that can be altered to decrease the risk are called causal risk factors.

Understanding risk factors

Some common features of risk factors are given below.

  • Risk factors may not negatively affect the individuals of different populations in the same manner.
  • Risk factors can vary in the population where the disease has just started appearing among individuals. They work differently in populations where the individuals are already affected and are in recovery.
  • In a population, the frequency of a risk factor is different from that of a disease or abnormality. Suppose all individuals of a population are exposed to the risk factor of consuming the same variety of salt in their food. In this case, the cause for an abnormality like hypertension cannot be easily detected among the members.

Risk factors of cancer and infectious diseases

Some risk factors for cancer are the following:

  • Exposure to carcinogens

Exposure of an individual to carcinogenic substances can trigger the chances of developing cancer. One serious problem with these chemical substances is that they can be present in the individual's surroundings, at home or the workplace.

Minerals such as asbestos can also trigger cancer development in an individual. Asbestos is usually found in industrial buildings and can be a severe threat to individuals working there.

  • Exposure to sun rays

Exposure to ultraviolet (UV) rays can cause mutations in the genetic material of skin cells and can result in the occurrence of cancer. Only some of the damages caused by the UV rays can be repaired by specific cell machinery. UV rays can cause abnormal growth of cells that leads to skin cancer.

  • Infections

Infection is a serious threat to the normal condition of the body. Viruses can change the genetic material of an individual and can activate cancer-causing genes in the body.

Risk factors of lung cancer

Risk factors of heart diseases

  • High Blood Pressure

High blood pressure can be a serious threat to heart abnormality in humans. With the increase in blood pressure, the workload of the heart also increases. This causes thickening of the cardiac muscles, which hinder the proper functioning of the heart. It increases the chances of a heart attack in the individual.

  • Obesity

The sedentary lifestyle and increased body weight of an individual pose a high risk of coronary diseases. Obese people are more prone to heart diseases as they have greater chances of having high cholesterol and blood pressure. A decrease in weight can lower the risk of developing heart diseases.

  • Diabetes

Diabetes can increase the blood sugar level of an individual, which damages the blood vessels in the body. Eventually, it affects the normal functioning of the heart and leads to coronary diseases.

An image shows the risk factors of heart diseases. The circular picture is divided into halves. One half depicts the list of non-modifiable risk factors, which are age, gender, genetic disorders and race ethnicity. Another half of the circle depicts the list of modifiable risk factors, which are high blood pressure, smoking, Diabetes mellitus, physical inactivity, obesity and high blood cholesterol.
Risk factors of heart diseases

Risk factors of diabetes

The risk factor for type 1 diabetes is the presence of diabetic patients in the individual's family history. Type 1 diabetes is primarily detected in individuals at a younger age. The risk factor for type 2 diabetes is excessive body weight. People older than 45 years of age are more prone to developing symptoms of this type of diabetes.

An image shows the risk factors of diabetes. The picture has five circles representing the risk factors of diabetes. The circles are labeled high blood pressure, smoking, sedentary lifestyle, high fat and overweight
Risk factors of diabetes

Prevention of risk factors

Prevention helps an individual to avoid developing the symptoms of any disease. A major prevention step is avoiding exposure to risk factors that lead to health problems.

To prevent the risk of developing diseases such as cancer, a person must avoid smoking, reduce alcohol consumption, and keep a healthy diet. He must protect himself from the harmful sun rays to prevent developing any skin abnormality. This way, the individual can remain fit and disease-free.

To prevent developing heart disorder, a person can regulate his weight by avoiding processed food and eating healthy food. This will help reduce the risk of high blood pressure and cholesterol.

Prevention from type 1 diabetes is not possible. However, prevention from type 2 diabetes can be done by avoiding sugary food. Food items that are rich in sugar increase the sugar level and insulin level in the blood. An increase in the physical activity level can also prevent diabetes by improving insulin cell sensitivity. Adequate intake of water also helps to avoid many diseases.

Common Mistakes

Students may think that all risk factors act similarly in every human population, but this is not true. Some populations may be more susceptible to a disease due to its risk factors. The risk factors work differently for the population of individuals undergoing treatment for the disease.

Students may think that a single exposure to a risk factor surely affects the health of an individual. In reality, continuous exposure to risk factors leads to abnormality in the individual's overall health.

Context and Applications

This article can be useful for the students taking professional examinations of higher secondary, undergraduate, and post-graduate levels, especially for the following:

  • High school level Biology
  • Bachelor of Science in Zoology
  • Master of Science in Zoology
  • Bachelor of Science in Pathology
  • Master of Science in Pathology
  • Diseases
  • Health problems
  • Medicines
  • Oncogenes

Practice Problems

Q1: Which of the following comes under fixed risk factors?

(a) Smoking

(b) Alcohol consumption

(c) Oncogenes

(d) Exposure to carcinogens

Correct choice: (c)

Q2: Which of the following is a risk factor for cancer?

(a) Viral infection

(b) High blood pressure

(c) High cholesterol

(d) Obesity

Correct choice: (a)

Q3: Which of the following disease counts diabetes as a risk factor?

(a) Cancer

(b) Heart disease

(c) Asthama

(d) Common cold

Correct choice: (b)

Q4: Which of the following cannot be prevented?

(a) Typhoid

(b) Jaundice

(c) Malaria

(d) Type 2 diabetes

Correct choice: (d)

Q5: Which rays cause cancer due to sun exposure?

(a) Ultraviolet rays

(b) Infrared rays

(c) Visible light

(d) Gamma rays

Correct choice: (a)

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