World
Cancer Day is observed on February 4 annually to raise awareness about the
disease. Cancer is one of the most dangerous non-transmissible disease that
plagues mankind. World Cancer Day aims to significantly reduce illness and death
caused by the disease.

World
Cancer Day is led by the Union for International Cancer Control (UICC), aiming
to reach the goals written in the World Cancer Declaration in 2008. The theme
for World Cancer Day from 2022-24 is ‘Close the Gap’, which focuses on
identifying and recognizing global disparities in cancer care.

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A lot of
research has been conducted into the possible causes of cancer and a number of
factors, such as food, health, lifestyle, environmental factors, etc contribute
to causing cancer. Read about some of them here:

Tobacco smoke:

Smoking is
one of the leading causes of cancer. Cigarettes, cigars and pipes all use dried
tobacco leaves, while other substances are also added to enhance the flavor.
The smoke from these substances contains a complex mixture of harmful chemicals,
with at least 70 of them known to cause cancer.

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Such cancer-causing
substances are called carcinogens.

Diet and physical activity:

Diet and
physical exercise have a significant role in the risk of cancer. Poor diet and
lack of physical activity can increase a person’s risk of cancer. The World
Cancer Research Fund estimates that at least 18% of all cancer cases in the
United States are related to obesity, physical inactivity, alcohol consumption
among other preventable reasons.

Radiation:

Ultraviolet
light and other kinds of radiation can cause skin cancer. Different types of UV
radiation have different energy levels and have affect a person differently. UV
light comes from the sun and man-made sources like tanning beds. Other than UV,
gamma rays, X-rays and Radon can also cause cancer.

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Infections:

Certain
infections can also cause cancer, with a number of bacteria, viruses and other
parasites known to be risks for several kinds of cancer in humans. Infections
are linked with 15% to 20% of all cancers worldwide.