Introduction
Cancer is a disease in which abnormal cells divide uncontrollably and destroy body tissue.
Cancer cells grow uncontrollably and spread to other parts of the body. Cancer can start almost anywhere in the human body, which is made up of trillions of cells.
Cancer is caused by mutations to the DNA within cells. The DNA inside a cell is packaged into a large number of individual genes, each of which contains a set of instructions telling the cell what functions to perform, as well as how to grow and divide.
Scientists have found that
chronic stress can wear down our body's defenses, lower our immune response, and make us more vulnerable.
Tobacco use, alcohol consumption, unhealthy diet, physical inactivity and air pollution are risk factors for cancer and other noncommunicable diseases. Some chronic infections are risk factors for cancer; this is a particular issue in low- and middle-income countries.
Specifically, high blood sugar levels lead to conditions such as high insulin levels and obesity, which both increase the risk for cancer.
In this article we are going to review the causes of cancer. However due to lack of space it is not possible to discuss all factors.Only main risk factors will be covered.
Factors for rising cases of cancer in India:.
(1):Aging and cancer:
Aging is the most important risk factor of malignant disease, the prevalence of which dramatically increases as adults age, reaching a peak around 85 or 90 years, when the incidence of new cancer diagnoses starts to decline and that of cardiovascular and other diseases ramps up.
Often our body repairs the damage, or damaged cells self-destruct. But sometimes the damage in a cell builds up, and the cell starts to behave differently. This is when it can grow out of control and develop into a cancer. As we age, there's more time for damage in our cells to build up, making cancer more likely.
Aging increases cancer risks in our bodies in several ways. The older we are, the higher the proportion we acquire of cells with mutations.
The incidence rates for cancer overall climb steadily as age increases,(I) from fewer than 25 cases per 100,000a
(iii) people in age groups under age 20, to about 350 per 100,000
(iii)people among those aged 45–49, to more than 1,000 per 100,000
(iv) people in age groups 60 years and older.
Aging increases cancer risks in our bodies in several ways. The older we are, the higher the proportion we acquire of cells with mutations.
(2) Smoking and cancer:
Smoking can cause cancer and then block your body from fighting it: Poisons in cigarette smoke can weaken the body's immune system, making it harder to kill cancer cells. When this happens, cancer cells keep growing without being stopped.
If you smoke one to five cigarettes per day, your risk is around 7.7%, and if you smoke more than 35 cigarettes per day, you'll have a 26.4% chance of lung cancer.
(3) Chewing tobacco and oral cancer;
Some of the chemicals contained in tobacco smoke and chewing tobacco are carcinogenic, meaning they can cause genetic changes in cells of the mouth cavity, leading to the development of oral cancer
Oral cancer most often occurs in people over the age of 40 and affects more than twice as many men as women. Most cancers in the mouth are related to tobacco use, drinking alcohol, or both, and most throat cancers are caused by the human papilloma virus (HPV)..
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(4) Diet and cancer:
High-fat, low-fibre diets may increase the risk of many cancers including bowel, lung, prostate and uterine cancers. Reducing alcohol intake and maintaining a healthy body weight may reduce the risk of many cancers.
And it's best to cut down on processed and red meat (like bacon and sausages), high-calorie foods (including fast food), sugary drinks (including fizzy drinks and energy drinks) and alcohol.
Your overall diet has a big role to play .
(5) Less activities and cancer:
The meaning of couch potato is a lazy and inactive person. especially : one who spends a great deal of time watching television and mobile.
A couch potato is a slang for someone who spends most of their time watching television and does not exercise or have any interesting hobbies.
Physically active adults have a significantly lower risk of developing several commonly occurring cancers, as well as lower risk of several other cancers. Research shows that adults who engage in greater amounts of physical activity have reduced risks of developing cancers of the: urinary bladder.
Being active decreases your risk of cancer, but sedentary behaviour is an independent risk factor. Even if you exercise 30 minutes or more every day, if you're sedentary for most of your days, you are still at an increased risk for cancer.
Getting less sleep is also associated with an increased risk of cancer, according to a study published in the journal Cancer.
One major study in young men suggests that regular running, fast walking and other aerobic exercise can significantly reduce the risk of nine types of cancer when you get older.
(6) Gene mutation and Cancer:
Cancer is caused by certain changes to genes, the basic physical units of inheritance. Genes are arranged in long strands of tightly packed DNA called chromosomes. Cancer is a genetic disease—that is, it is caused by changes to genes that control the way our cells function, especially how they grow and divide
(7) Alcohol and cancer:
Some studies show that drinking three or more alcoholic drinks per day increases the risk of stomach and pancreatic cancers. Drinking alcohol may also increase prostate cancer risk. All alcoholic drinks—including red and white wine, beer, and liquor—are linked with cancer.
Alcohol is a toxic, psychoactive, and dependence-producing substance and has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer decades ago – this is the highest risk group, which also includes asbestos, radiation and tobacco.
Because the cytotoxic activity of ethanol is concentration-dependent, the risk of these cancers will not only increase with increasing amounts of ethanol, but also with the increasing concentrations; an ounce of whisky is probably more carcinogenic when taken undiluted than when taken mixed with non-alcoholic beverages.
(8) Hormone replacement therapy (HRT) and breast cancer:
Higher-dose combination HRT increases breast cancer risk more than lower-dose combination HRT. Combination HRT also increases the likelihood that the cancer may be found at a more advanced stage. Combination HRT is linked to increased breast density, which can make it harder for mammograms to detect breast cancer.
Breast cancer: combined HRT slightly increases the risk of breast cancer. This increased risk gets bigger the longer HRT is used. When HRT is stopped, the increased risk goes down over time. This takes longer, the longer that HRT was used.
(9) Environmental pollution and cancer:
Exposure to air pollution can lead to cancer, stroke, respiratory, cardiovascular diseases and other health issues. Nearly half of lung cancer cases in people who have never smoked are estimated to be related to air pollution.
Air pollution includes outdoor and indoor air pollution. Both can increase the risk of lung cancer as well as respiratory and heart diseases.
Chemicals in the environment ;Benzene, asbestos, vinyl chloride, radon, arsenic, and trichloroethylene are examples of toxic substances that can increase the risk of cancer when people are exposed to them.
(10) weakened immunity and cancer :
With increased mutations and weakened immunity, you are at a greater risk of getting cancer. A less effective immune system makes you more susceptible to illness. The thymus gland, a part of your immune system, develops T cells. These play an essential role in building your immunity.
Cancer cells are not antigens, as viruses and bacteria are. Instead, they are mutated versions of your body's own cells. That means your immune system doesn't get the signal to fight cancer cells the way it does when you encounter germs.
The T cells see cancer as “foreign” cells that don't belong in the body. The T cells attack and try to destroy the cancerous cells. When the cancer cells are killed, a “checkpoint” in the immune system stops the T cells from attacking. This protects healthy cells.
Steps to boost your immune system:
•Eat healthy. Like any engine, your body relies on the fuel you give it.
•Get exercise. There's no getting away from this basic truth.
•Aim for good sleep. Don't underestimate the power of rest.
•Eliminate tobacco and avoid alcohol.
•Reduce stress
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(11) Obesity and cancer:
being overweight or obese is linked to an increased risk of developing several types of cancer:
•Breast cancer: Obesity is associated with increased risk of breast cancer in post-menopausal women. This is due to excess estrogen production by fat tissue.
•Colorectal cancer: Obesity is linked to colorectal cancer due to higher insulin levels, which can promote the growth of colon cancer cells.
•Uterine cancer: Obesity is linked to uterine cancer.
•Ovarian cancer: Obesity is linked to ovarian cancer.
• Kidney cancer: Obesity is linked to kidney cancer.
• Esophageal cancer: Obesity is linked to esophageal cancer.
•Pancreatic cancer: Obesity is linked to pancreatic cancer.
Obesity is a complex condition that can increase the risk of many other diseases, including cardiovascular disease and Type II diabetes.
While obesity increases the risk of cancer, not everyone who is overweight or obese will develop cancer. Eating a healthy diet, being physically active, and maintaining a healthy weight can help reduce the risk of some cancers.
Excess fat is associated with chronic inflammation, which research has proven to be linked to cancer by promoting cell mutation and tumor growth
Obesity produces excess amounts of estrogen, high levels of which have been associated with increased risks of breast, endometrial, ovarian, and some other cancer in females.
Overweight and obesity is the second biggest cause of cancer.
Being overweight doesn't mean that you'll definitely develop cancer. But if you are overweight you are more likely to get cancer than if you are a healthy weight.
Still, there's growing evidence that weight loss might reduce the risk of some types of cancer, such as breast cancer (after menopause) and endometrial cancer.
Reducing calories and practicing healthier eating habits are key to overcoming obesity. Although you may lose weight quickly at first, steady weight loss over the long term is considered the safest way to lose weight. It's also the best way to keep weight off permanently. There is no best weight-loss diet.
(12) Radiation and cancer:
Cancers associated with high dose exposure include leukemia, breast, bladder, colon, liver, lung, esophagus, ovarian, multiple myeloma, and stomach cancers.
(13)Certain Chronic diseases cause cancer:
Some chronic health conditions, such as ulcerative colitis, can increase the risk of developing certain cancers.
Infections can cause certain cancers in a variety of ways including by affecting the genes in your cells, by causing inflammation in your body.
Researchers know that there are several viruses that can lead to cancer. For example, the human papillomavirus (HPV) can cause cervical and several other cancers. And hepatitis C can lead to liver cancer and non-Hodgkin's lymphoma.
(14) Diabetes and Cancer:
Not only are people with diabetes - especially Type II diabetes - more likely to develop heart disease or kidney disease, people with diabetes also are at increased risk for cancer. The risk is highest for liver, pancreatic, colorectal, endometrial, breast and bladder cancer.
If you have diabetes, you can be more at risk of developing certain types of cancer. It's estimated that 1 in 5 (20%) of cancer patients have diabetes.
Those with uncomplicated diabetes were at a minimally or insignificantly higher risk of all‐cause and cancer specific death.
Synopsis:
Cancer is a preventable disease that requires major Lifestyle Changes.
This year, more than one million Americans and more than 10 million people worldwide are expected to be diagnosed with cancer, a disease commonly believed to be preventable. Only 5–10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90–95% have their roots in the environment and lifestyle. The lifestyle factors include cigarette smoking, diet (fried foods, red meat), alcohol, sun exposure, environmental pollutants, infections, stress, obesity, and physical inactivity. The evidence indicates that of all cancer-related deaths, almost 25–30% are due to tobacco, as many as 30–35% are linked to diet, about 15–20% are due to infections, and the remaining percentage are due to other factors like radiation, stress, physical activity, environmental pollutants etc. Therefore, cancer prevention requires smoking cessation, increased ingestion of fruits and vegetables, moderate use of alcohol, caloric restriction, exercise, avoidance of direct exposure to sunlight, minimal meat consumption, use of whole grains, use of vaccinations, and regular check-ups. In this review, we present evidence that inflammation is the link between the agents/factors that cause cancer and the agents that prevent it. In addition, we provide evidence that cancer is a preventable disease that requires major lifestyle changes.impact on cancer risk than any individual food or ingredients.
Information compiled by: Dr. Bhairavsinh Raol
