Cancer is undoubtedly on the rise. It affects more and more people around us, from within our family and our circle of friends. Some of you might have even been diagnosed with cancer yourselves, either recently or in the past. As I dive more and more in studying cancer and its link to nutrition, I realize that many people think of the word cancer as a taboo, a topic they never want to talk about.
But I often wonder, is this a wise thing to do? In today’s world with such alarming cancer rates and even worse, with such alarming cancer incidence predictions, can we afford not to think about this serious disease?
The old saying says “know your enemy”, so I strongly believe that as a global community we should all really get to know what cancer is, and most importantly learn how to prevent it.
What is cancer?
There are more than 200 types of cancer. Cancer is the name given to a collection of related diseases which occur when cells become damaged and get out of control.
Cancer can start almost anywhere in the body, which is made up of trillions of cells. In all types of cancer, some of the body’s cells begin to “rebel” and stop following the rules of healthy cells.
Healthy cells grow and divide to form new cells as the body needs them. Usually the body has just the right number of each type of cell. The body produces signals to control how much and how often cells divide. When cells grow old or become damaged, they die with a process called apoptosis and new cells take their place.
When cancer develops, however, this orderly process breaks down. Changes in the genetic code (DNA) of cells make them grow out of control. Cells with damaged DNA have the ability to escape apoptosis and survive. These cells then start dividing without stopping and may eventually form a tumor.
Photo from http://www.healthykarnataka.org/operational-guidelines/cancer-cervix/overview-of-cervical-carcinoma
In this figure the division of normal cells is compared to the division of cells with damaged DNA which is uncontrolled and eventually leads to cancer initiation.
Many cancers form solid tumors, which are masses of tissue. Cancers of the blood, such as leukemia, generally do not form solid tumors.
Cancerous tumors are malignant, which means they can spread into or invade other tissues. They break off and travel to distant places in the body through the blood or the lymph system, where they form new tumors far from the original tumor.
Some tumors are benign. Unlike malignant tumors, benign tumors do not spread into or invade other tissues. Benign tumors can sometimes be quite large, however. When removed, they usually don’t grow back, whereas malignant tumors sometimes do. Unlike most benign tumors elsewhere in the body, benign brain tumors can be life threatening.
A significant factor that allows the survival of cancerous cells is their ability to form new blood vessels, known as angiogenesis. Angiogenesis allows them to have their own supply of oxygen and nutrients necessary for their growth.
Cancer takes years to form
Not all rebel cells lead to cancer. This out of order cell behavior happens regularly over one’s lifespan, without necessarily leading to cancer. Actually, cells that can develop into cancer are often present in our bodies; they’re simply waiting for something to push them over the edge, to cause them to behave abnormally, to divide, multiply and invade.
Cancer development is gradual. It evolves over many years or even decades. This big time window allows us to intervene in order to keep potential tumors in a dormant state and to prevent them from developing and maturing.
Balance between cancer promoting and cancer preventing factors
More than half of the cancers occurring today are preventable by applying knowledge that is already available to scientists. There are many modifiable risk factors related to the development of cancer. The list is big but smoking, being overweight, lack of exercise and a bad diet are the main ones.
When it comes to diet, a low intake of fruits and vegetables together with a high intake of refined western foods, rich in sugar, salt and bad fats create an internal environment that promotes cancer.
On the contrary, a carefully selected diet has the ability to boost the body’s natural defenses against cancer. By strengthening the immune system, enhancing the body’s ability to detoxify, reducing inflammation and choosing a diet rich in natural anti-cancer molecules the body can fight cancer at its first stages of existence and increase the body’s ability to stabilize tumors over very long periods of time.
So, in a person’s lifetime, the balance between the cancer promoting and the cancer preventing factors will judge the body’s ability to remain healthy and keep cancer away.
Cancer is preventable
The World Health Organization estimates that up to 30-70% of cancers are preventable. Data from other official sources like the American Institute for Cancer Research (AICR), estimate that eating a healthful diet, being active and maintaining a healthful weight can prevent as many as 35-40% of cancers. The AICR suggests diet, weight and physical activity as the 3 cornerstones of cancer prevention and advises people to:
- Choose mostly plant foods, limit red and avoid processed meat,
- Aim to be at a healthy weight throughout life and
- Be physically active every day in any way for 30 minutes or more.
References:
- http://www.cancer.gov/about-cancer/what-is-cancer#differences-cancer-cells-normal-cells
- Sharon R.Pine and Wenyu Liu. Asymmetric cell division and template DNA co-segregation in cancer stem cells. Frontiers in Oncology; 21 August 2014 http://dx.doi.org/10.3389/fonc.2014.00226 or
- http://www.healthykarnataka.org/operational-guidelines/cancer-cervix/overview-of-cervical-carcinoma
- World Health Organization: http://www.who.int/cancer/prevention/en/, accessed 22/10/2014
- American Institute for Cancer Research: http://www.aicr.org/reduce-your-cancer-risk/recommendations-for-cancer-prevention
