What Causes Cancer - Nine Changes You Can Make to Reduce Your Risk

Cancer is a word that draws forth emotion, tension, fear, doubt, and controversy.

Shrouded by convoluted concepts and origins, it’s unsurprising that many myths and rumors surround how one can come to be afflicted by the dreaded six-letter word cancer.

Cell phones, artificial sweeteners, and even deodorants have at some point shouldered the blame for causing certain cancers. 

But, the truth is that cancer is not a new or human-made disease. In fact, the many manifestations of cancer were frequently described by scholars throughout ancient Egypt and Greece.

In 2014, scientists discovered widespread cancer in a 3000-year-old skeleton of a man from Ancient Nubia. Researchers have even found evidence of cancer in dinosaur bones! 

With the big “C” dating back as far as we know, how much do today’s environment and lifestyle have to do with getting cancer? Let’s have a closer look at the causes of cancer, including what you can do to minimize your risk.

Some Things We Just Can’t Change

Like death and taxes, some factors are out of our control. Let’s first discuss two known contributors to cancer that are set in stone - your gender and age.

Gender heralds bad tidings, that is if you happen to be a male. Outside of cancers that are specific to one sex or the other, most cancers occur about two to three times more often in men than women.

Women do have their own set of obstacles to navigate through. For example, women who do not have any children have a small increased risk of getting breast, ovarian, and endometrial cancers.

However, your age is hands-down your most significant risk factor for getting cancer. Quite simply, a majority of cancers have a progressively higher chance of occurring as you get older. As a whole, we are living to be older than ever before.

But with old age comes more time for the slow and progressive accumulation of damage to our DNA. We naturally have a pretty sophisticated defense system against this damage, employing a number of checkpoint systems to keep any cells from acting out.

However, the summation of these insults eventually causes these safeguards to fail, allowing cancers to grow and spread uncontrolled.

The Modifiable Nine

Researchers have tirelessly sought out the causes of cancer that are most amenable to change. We’ve compiled a list of nine everyday behaviors, which if altered, could reduce your risk of developing certain types of cancer. The following are the voluntary vices, habits, and lifestyle choices that have been most scientifically tethered to causing cancer:


They’ve come to be known as cancer sticks for a good reason. Tobacco use stands as the most preventable cause of cancer, single-handedly accounting for 21% of cancer deaths across the world.

Research has shown us that this addiction causes you to lose on average about 13 years of life, with around half of all smokers ultimately succumbing to a tobacco-related disease. 

It’s common knowledge that smoking dramatically increases your risk of getting lung cancer, a threat determined to be a 20-fold increase.

However, you may be surprised to know just how many other types of cancer have been convincingly linked to smoking. The non-exhaustive list includes blood, mouth, nose, throat, stomach, liver, kidney, bowel, prostate, and bladder cancer!

So how does inhaling some smoke reap all this destruction?

The components comprising tobacco smoke hit the body’s defense systems from multiple angles – direct toxicity to tissues, disruption of natural protective barriers, in addition to general irritation and inflammation. 

How to Decrease Your Risk:

Either pledge to quit, or never start! You should know the risk isn’t limited to cigarette smoking, applying to cigars, smokeless tobacco, and even secondhand-smoke. Increased risk even with just environmental exposure should be enough to motivate you to help your friends quit.

Helpful tactics proven to work include counseling by a healthcare professional, behavioral therapy or support groups, and nicotine replacement or other medications. (10)

What You Eat

An area that many struggles with, the convenient fast-food stop or greasy burger can sometimes be irresistible in today’s hectic world.

While there has been no area more studied in relation to its cancer-causing risk, the results have been mixed, to say the least. Let’s break down the evidence for a few of the more controversial types of food: 

Dietary fat has long been speculated as a potential cause for the disparity in certain types of cancer between countries, most convincingly demonstrated in prostate cancer.

Foods containing a combination of high alpha-linolenic acid and low standard linoleic acid, such as red meat in dairy products, has been mainly linked to increased rates. This connection is thought to be due to lower testosterone levels in men who eat less fat.

The truth may lie in the fact that on a per gram basis, fat has more calories than carbohydrates, protein, and alcohol. This is consistent with the finding that more calories, regardless of source, causes weight gain and therefore increased cancer risk. 

Red meat, when eaten judiciously, has been tied to an increased risk of colon cancer. The research proved most convincing when evaluating processed meats. Studies have shown an 18% increase in colon cancer risk for every 50 grams of processed meat consumed a day.

This equates to only 2 and a half slices of baloney! Even further, unregulated red meat consumption has additionally been associated with an increase in your chances of dying from all cancers.

Fruits and vegetables have been found to have at least a mild protective effect when it comes to getting many cancers.

This protection occurs at a relatively low threshold, with studies showing a benefit at 100 grams of fruit or vegetables per day.

One particularly interesting association has been found with a compound known as lycopene found in tomatoes, which has been suggested to decrease your risk of prostate cancer significantly.

How to Decrease Your Risk:

Eating healthy is difficult, and the amount of information on this topic can quickly feel overwhelming. The World Cancer Research Fund, in evaluation of the myriad data on this topic, most recently issued a set of critical, overarching recommendations for those looking to lower their risk of cancer:

  1. Limit energy-dense foods such as sugary drinks;
  2. Consume mostly plant-based foods;
  3. Limit red meat, and avoid processed meat;
  4. Limit salt consumption; and
  5. Avoid moldy grains (cereals) and legumes. 

The Mediterranean diet, high in fruits, vegetables, nuts, beans, fish and olive oil, has subsequently been found to reduce overall cancer risk by 12%. 

Physical (In)activity: Did you know that more than 60% of adults in the United States are not regularly active? Even more alarming, almost a quarter of all adults are almost entirely sedentary!

While we are well aware that a lazy lifestyle is highly associated with obesity, diabetes, and sleep apnea, studies have shown us that low physical activity is associated with 5% of cancer deaths.

You are probably wondering what kind of cancers would be associated with a lack of exercise.

Research out of Japan has shown us that moderate physical activity was associated with a decreased risk for breast, colon, liver, pancreatic, and stomach cancer.

In some cases, the reduced risk was more than 25%!

It has been speculated that physical activity is protective against cancer via several mechanisms.

The most popular theories include improving immune system function, regulating inflammatory agents known as prostaglandins, and lowering the amount of insulin, hormones, and growth factors circulating in your blood. 

How to Decrease Your Risk:

While the optimal length, intensity, and frequency of exercise to reduce cancer risk are still unknown, these recommendations do exist for maintaining good health in general.

According to the American Heart Association, adults should achieve a minimum of 30 minutes of moderate-intensity aerobic exercise 5 days a week or 20 minutes of vigorous exercise 3 days a week.

You should note that this is considered the minimum, and it’s been well-established that exercising past these lower limits will yield greater health benefits. 

Being Overweight:

Excess body weight has been associated with an increased risk for many types of cancer, with obesity estimated to cause 20% of all cancers!

Obesity had a particularly adverse effect on your chances of getting hormone-related cancers, such as endometrial cancer, in which it is accountable for a shocking 41% of cases.

While undoubtedly complex, it is thought that being overweight causes cancers through inflammation and increased levels of hormones triggered by the fat.

How to Decrease Your Risk:

While it may be difficult, the good news is that losing weight has been highly correlated with a decreased risk of getting or dying from cancer.

Diet and exercise are paramount, however losing weight can be very difficult and requires an exorbitant amount of commitment. According to the Centers for Disease Control and Prevention, reducing your daily calorie intake by 500-1000 can equate to losing 1-2 pounds per week.

You should keep in mind that even modest weight loss can be extremely beneficial to your health overall, including a lowering of blood pressure, cholesterol, and blood sugar.

However, if you have tried every diet and exercise plan out there to no avail, you shouldn’t lose hope. Some individuals require some additional help, and you should not be timid about asking your healthcare provider about the many options available to you.

More extreme measures for obesity, such as weight loss surgery, has been shown to reduce your risk of dying from cancer by 60%. 

Drinking Too Much:

Excessive alcohol drinking increases the risk of a number of cancers.

A very large study of one million women found that even one alcoholic beverage a day slightly increased the risk for mouth, throat, breast, liver, and rectal cancers.

According to the study, each additional drink past this added another 6% risk!

Another large study spanning 8 European countries found alcohol to account for a total of 10% of cancers in men and 3% in women. 

Like many others on this list, the way alcohol causes cancer is most likely multifaceted. Some think alcohol may inadvertently act as a transporter for cancer-causing particles to dissolve and pass into the body’s cells.

Alcohol also is known to increase levels of estrogen and decrease folate in the blood. Finally, the intoxicating substance acts as an irritant which disrupts many of the body’s normal functions of metabolism. 

How to Decrease Your Risk:

If you are going to enjoy an occasional drink, just ensure to do it responsibly. Men should limit themselves to two alcoholic beverages a day, while females should try to call it quits after one.

The cancer risk is partially offset by some benefits of alcohol when consumed moderation, including a small bump in “good” cholesterol, a decreased risk of blood clots, and some antioxidant activity.


An estimated 17% of new cancers are due to infections. Many viruses can enter into the body’s cells, where they take over the machinery for their personal use.

Since the goal of many viruses is to replicate itself as many times as possible, this involves shutting down the regulation that keeps cells from dividing uncontrollably and causing cancer.

Through this mechanism, multiple viruses are responsible for cervical, liver, skin, and several blood cancers among others.

How to Decrease Your Risk:

The majority of these viruses are spread from one person to another through contact with infected blood or other body fluids.

Many advances have already been put in place to minimize unwanted transmission, included more stringent screening of blood products, regulations on tattooing, single-use programs for needles, and the creation of artificial blood replacement products.

Regardless, the most important thing for you to do is to ensure that both you and your children are up to date on vaccinations... which can prevent many of these viruses from developing into cancer.

Too Much Sun:

More than 1 million skin cancers are diagnosed every year, about 70,000 of which are of the deadly melanoma variant.

Radiation emitted from the sun is the primary cause of all of these skin cancers, with total lifetime exposure closely correlating to the rate of occurrence.

This isn’t to say you should never leave your house. As best we know, it is prolonged, unprotected exposure to these ultraviolet rays.

And these rays cause genetic mutations and negatively impacts the skin’s ability to keep out foreign invaders.

And yes, tanning beds do expose you to ultraviolet light, with research now showing us that utilization before age 35 increases your risk of melanoma by 75%! 

How to Decrease Your Risk:

Everyone should limit direct sun exposure during the peak hours between 10 AM and 3 PM. Wearing sunglasses, hats, or other protecting clothing can be helpful.

Finally, sunscreen is essential, particularly in young children who are rapidly accumulating lifetime exposure by enjoying their summers and holidays off. 

Where You Work:

Your job might be inherently putting you at a higher risk for cancer.

Some occupations have been classified as cancer-causing to humans, with subsequent identification of a specific chemical or agent which does the damage.

For instance, the manufacture of shoes has been linked to both lung cancer due to leather dust, and a type of blood cancer from use of a cleaning solution containing a chemical known as benzene.

A comprehensive list of more than one hundred of these cancer-causing agents has been meticulously compiled by the IARC.

Where You Live:

There’s no question our surroundings contribute to our risk of developing certain cancers.

Some countries, which embrace radically different diets or social activity, have as much as a 20-fold difference between how often certain cancers occur.

In fact, researchers have shown that if you migrate from an area with a low incidence of a cancer to an area with a high rate of that same cancer.

Your family will gradually acquire the cancer risk of the new space within one to three generations.

This point has been further exemplified by the rise of lung cancer in the United States over the last 50 years, compared to the fall in stomach cancer over the same period.

Despite being completely modifiable, these nine factors account for more a staggering one-third of cancer deaths.

Start making changes to reduce your risk today!

Final Thoughts

  • With the world’s population getting older and living longer, cancer is becoming more prevalent than ever.
  • A combination of an active lifestyle, healthy eating, and enjoying life in moderation can greatly decrease your risk of developing many cancers.

Food, Health & You
Guest Author:
Peter Grossman, 

Physician (MD), Medical Writer, and Consultant

© 2021 foodhealthandyou.com All rights reserved.