It is no secret that cancer is on the rise all over the world. It is estimated that nearly 40% of men and women worldwide will receive a cancer diagnosis at some point in their lifetime. (1) While there continue to be incredible advancements and discoveries in the field of cancer testing, treatments, and potential cures, this reality remains the same.
The only real way to beat cancer is to prevent it all together. The challenge is that cancer prevention looks different for each individual and cannot be done for you: You have to take control and take action against your own personal risk factors.
This means that the first step in cancer prevention is knowing the risk factors for cancer, understanding which ones apply to you, and realizing your personal risk so that you can make the changes necessary to lower them.
The following are fifteen of the most prominent risk factors that will determine whether or not you get cancer. Find out which of these apply to you and talk to your doctor about steps you can take to lower your cancer risk.
15 Risk Factors for Cancer Everyone Should Know
1. Genetic Predisposition
Cancer is a genetic mutation, which is why our genes and our family history of cancer can tell us so much about our own risk for developing cancer. (2, 3, 4)
For example, if your great-grandmother had breast cancer, that mutated gene is gets passed down to your grandmother, your mother, and then to you. Now, just because someone in your family had cancer, does not mean you are guaranteed to get it, but it does put you at a much greater risk.
There are over one hundred known cancer predisposition genes, and the presence of any of these will help to determine your level of risk for developing different types of cancer. Cancer predisposition genes provide scientists with crucial information on the pathology of cancer, how it grows, and especially in what causes it. (2)
Genetic testing is available to determine if you have any of the known cancer genes and is routine for high-risk people (those who have a number of cancer cases in their family). If you are concerned about whether or not you have cancer genes in your DNA, talk to your doctor about being tested.
Unfortunately, you can’t change your DNA to lower your risk. You can, however, take steps to remove other cancer risk factors from your life.
2. Beneficial Bacteria and Your Microbiome
More and more research is coming out about the importance of having a healthy gut with the right balance of “good”bacteria and very little “bad” bacteria, for both cancer and other types of disease. A decrease in beneficial bacteria in your GI tract is associated with an increase in inflammation, which is known to cause cancer. There are three main areas along your digestive tract that without the proper balance of healthy bacteria, inflammation and cancer will grow:
Currently, the role of oral microbiota in fighting or promoting cancer is not fully understood. What we do know, is that the bacteria in your mouth helps to make cytokines and other inflammtion mediators, which may help prevent cancer.
There is an association with poor oral health and a number of cancers, including pancreatic and gastrointestinal cancer. Most cancer cases due to oral microorganisms occur when an infection is present in the mouth, and there is an influx of bad bacteria and inflammation. In most cases, proper oral hygeine will prevent these infections and maintain a proper balance of bacteria in your mouth. (5)
Upper Digestive Tract
Lower numbers of important upper digestive tract bacteria have been correlated with an increase in esophagael and stomach cancers. This low population of bacteria has also been associated with chronic esophagael diseases and inflammation, which raises your risk for cancer. (6)
Gut and Intestines
A decrease in beneficial bacteria in the intestines is associated with inflammation and an increased risk for colorectal cancers. Again, this inflammation causes chronic diseases, such as colitis, which raises your risk for developing colon cancer and other cancers of the lower digestive tract. (7, 8, 9)
Exciting research, however, shows the promise of eating a diet high in pre- and probiotic foods will keep your digestive tract and gut bacteria in check, prevent chronic illness associated with inflammation of the GI tract, and help to lower your risk for developing cancer. Some studies have even found that beneficial bacteria can not only counteract dietary causes of cancer, but genetic predisposition as well. (10)
3. Processed Meats and Red Meats
The World Health Organization has classified processed meats as a carcinogen (a cancer-causing substance). Processed meats include:
Some deli meats
Red meats include:
Essentially, any meat that has been treated (smoked, salted, cured, or fermented) to flavor or preserve it. (11) While the occasional consumption of these meats won’t cause harm, eating them every day will raise your risk of cancer by an entire percentage. (11)
One of the issues with red meats and processed meats is that statistically, those who eat them frequently also have a lower intake of cancer-fighting fruits and vegetables. Everyone should be limiting red meat consumption to once or twice a week at most, using healthy cooking practices such as baking or broiling, and eating a variety of colorful vegetables along with it. Everyone should strive to eliminate highly processed meats from their diets entirely. (12)
4. Cruciferous Vegetables
Cruciferous vegetables are one of the best sources of glucosinolates and their hydrolysis products, including indoles and isothiocyanates. What these strangely named molecules do is alter the way your sex hormones (estrogen, testosterone, and progesterone) act or are metabolized in a way that inhibits the development of hormone-sensitive cancers. (13)
Though more research needs to be done to determine the full impact, not including cruciferous vegetables, such as broccoli, kale, cauliflower, and brussels sprouts means you won’t have these hormone-inhibiting products fighting off cancerous mutations.
Cancer is caused by free radicals and reactive oxygen species that occur naturally in the body during chemical reactions or when we are exposed to environmental toxins. Antioxidants and phytochemicals are free-radical scavengers: they prevent oxidative damage to our DNA and cell membranes by neutralizing and getting rid of these molecules, lowering our risk of developing cancer. (12, 14)
Our body makes some of its own antioxidants, however, this alone is not enough and it is crucial that we also get them from our diet. The primary antioxidants and antioxidant-functioning nutrients that we should eat every day are (12, 15):
Vitamin E: Almonds, spinach, sweet potatoes, avocados
Vitamin C: Oranges, red peppers, kale, brussels sprouts
Carotenoids: Carrots, sweet potatoes, dark leafy greens, tomatoes
Selenium: Brazil nuts, yellow-fin tuna, halibut, sardines
Folate: lentils, legumes, avocado, dark green vegetables
Without consuming enough antioxidants in your diet, your body can’t keep up with the oxidative damage causing free radicals that it is exposed to every day, increasing your risk of cancer and other diseases.
Whether from a day spent at the beach or a tanning bed, the scientific community has all agreed on one thing: Tanning is bad for you.
A tan, even just a light one, is still a sign of damage to your skin’s cells from the ultraviolet (UV) rays from the sun or tanning bed lights. Burns, of course, are even worse. Not only do these damage UV rays cause early signs of aging, such as sun spots, wrinkles, and lines, but they also are the number one cause of melanoma, aka skin cancer. (16)
While yes, vitamin D from the sun is important for our health, this can be achieved without the cell damage that comes along with too much sun exposure. More importantly, we only synthesize vitamin D from UVB rays, not UVA, and the lights in tanning salons only emit UVA. (17)
People who first use a tanning bed before the age of 35 are 75% more likely to get cancer, and 90% of melanomas are caused by UV exposure. (16, 17) Protect yourself from cancer: Don’t tan.
7. Vitamin D
While more research is being done, studies have found that people who live in more southern climates and who have higher serum vitamin D levels have lower mortality rates from cancer. (18)
The best way to get adequate vitamin D intake is by synthesizing it in our skin cells from the UVB rays from the sun. Of course, this gets tricky, knowing that over-exposure to the sun can cause cancer, and is even further made difficult for those living in northern climates whose skin does not see the sun for more than half of the year.
Thankfully, you can get proper intake of vitamin D from sunlight without having to sit in the sun for hours. The Vitamin D council suggests you go outside at Mid-day (when the UV rays are strongest) in shorts and a tank top, so that your legs and arms are exposed. For fair-skinned people, you will synthesize enough in ten to fifteen minutes, for adequate levels can be achieved in an hour, or potentially more for very dark skinned individuals. The rest of the time, you should be practicing safe sun exposure, wearing hats and sun protective clothing, and sun screen when necessary.
For anyone living in colder climates, taking a mid-day sun break probably isn’t an option. In that case, it is important to include plenty of vitamin D-rich foods in your diet, and you may want to consider taking a supplement throughout the fall and winter months.
8. Sedentary Lifestyle
At this point, we are well aware that sitting all day, every day is just as bad for you as smoking. Sedentary behavior increases your risk for a wide variety of chronic diseases, cancer included. (20, 21)
Amount of time spent in non-active pursuits (sitting at work, driving, reading a book, watching TV, etc.) as been particularly linked to an increased risk for ovarian cancer, prostate cancer, colorectal cancer, endometrial cancer, and breast cancer. (20, 21)
A regular exercise routine is important and helpful at decreasing your risk for cancer, however if you spend the other fifteen hours of your day sitting, you aren’t achieving as much as you think. Activity needs to be incorporated into your day beyond your regularly scheduled exercise: Take walks on lunch, get off the bus a couple of stops early, park at the back of the parking lot, and walk and bike places when you can. The less time you spend sitting on your butt, the better! (12)
9. Being Overweight or Obese
Being overweight or obese contributes to 20% of all cancer diagnosed in America, and this excess body weight causes one in five cancer-related deaths. Excess fat on the body raises cancer risk because of its effects on: (12, 22)
Immune system function and increased inflammation
Hormone levels (especially insulin and estrogen)
Factors that regulate cell growth
Proteins that influence how your body uses and produces sex hormones
Losing weight and maintaining a healthy weight will most certainly lower your risk of developing cancer.
10. Refined Sugars
Sugar has been getting a lot of press-time lately, as it has taken the place of fat as the most “evil” of all foods. In reality, not all sugar is bad (ie. naturally occurring fruits sugars) and our bodies need sugar to function properly.
Some information has come out that states that sugar causes cancer to grow rapidly in the body. There is some evidence that large amounts of sugar may contribute to certain cancers, most these claims have yet to be properly studied and proven. That being said, there is a correlation between people who eat diets high in refined sugars and being overweight and obese. As already discussed, carrying around excess body weight will increase your risk of cancer. (23, 24)
Foods that contain refined, highly processed sugars usually also contain very little beneficial nutrients, are high in calories, and other hidden, dangerous additives. Diets that are high in refined sugars and processed foods also promote inflammation in the body, which we know contributes to chronic illness and cancer. (25)
Cut the refined, processed sugary foods out of your diet, lose the weight, and you will decrease your risk of developing cancer.
Inflammation in your body is at the root of nearly every chronic disease: Diabetes, arthritis, migraines, IBS, and the list goes on. The same is true for inflammation and cancer.
Long-term, chronic inflammation from infection and other sources is directly connected to tissue damage and the development of cancer. (25) Decreasing your chances of contracting infections and diseases will lower your risk of inflammation and cancer, but much of the chronic inflammation we experience in North America is due to our poor lifestyle choices.
As already mentioned, highly processed foods, refined sugars and carbohydrates, treated foods and those high in unhealthy fats all cause inflammation inside your body. Thankfully, there are foods that have anti-inflammatory properties and will help to lower your risk of cancer. These foods include:
Vegetables and fruits
Herbs, such as oregano
12. Carcinogenic Substances
There are hundreds of known and probable cancer-causing substances in our everyday environment. For a complete list, visit here.
Everyday we are all exposed to toxins and chemicals. People in certain jobs and careers are exposed to more dangerous and known carcinogens because of their occupation than others.
Many people who work in the industrial sector, like construction, metal work, and manufacturing, or those who work in landscaping, conventional farming, transportation (driving or flying), and even cosmetics (barbers, hair dressers, and estheticians) are exposed to a variety of toxic chemicals. Asbestos, diesel engine exhaust, hydrocarbons, formaldehyde, arsenic, and various types of radiation are just some of the environmental toxins that are known to cause cancer.
For a full list of occupational hazardous chemicals and how to decrease your exposure, go here.
Even if you do not work in a particularly hazardous job, you are still exposed to thousands of chemicals before you even step out of your own home. There are chemicals and toxins in household products, such as detergents, cleaners, air fresheners, cosmetics, and shampoos, not to mention radiation from cell phones and other devices. Ways to limit your exposure to dangerous chemicals in your home are: (27, 28)
Use natural, organic cosmetics
Use natural air fresheners
Limit cell phone use and do not keep your cell phone in your pocket, bra, or anywhere else directly on your person
Have up to date air filtration systems
Drink filtered water
These are just a few steps you can take to decrease you and your family’s exposure to harmful chemicals and pollution. (27, 28)
13. X-Rays and CT Scans
X-Rays and gamma rays are known carcinogens, and high doses of these rays will cause cancer. This has been seen in people exposed through nuclear accident or warfare, people who have undergone radiation therapy for cancer and other conditions, and people in certain occupations, such as uranium miners. (29)
In terms of lower doses of radiation from x-rays and ct scans for bone breaks, fractures, and other conditions, more research is being done. In many cases, the benefits outweigh the risks, however there is a limit as to how many x-rays and ct scans you can receive for each part of your body. Once you reach those limits, you can no longer have those procedures done. (29)
Ultrasound and MRI are safe alternatives for x-rays and ct scans, however depending on the procedure or what imaging needs to be done, they may not always be a viable option. (30)
14. Unprotected Sex and STIs
Sexually transmitted infections, primarily HPV (human papilloma virus) from having unprotected sex can lead to cervical cancer in women and penile cancer in men. (31)
You can protect yourself from contracting HPV by using condoms and practicing safe sex, and women should keep up with their scheduled PAP smears to monitor their sexual health. There is a vaccine available for HPV, if you do not already have the vaccination, talk to your doctor about your options and any risks to make an informed decision as to whether this vaccine is right for you. (32)
15. Smoking and Alcohol
Cigarette smoking is currently one of the leading causes of cancer death. There are thousands of toxic chemicals in cigarettes beyond just nicotine. Even just “occasional” or “social” smoking raises your risk for cancer. There is no hiding this one: If you want to drastically decrease your risk of cancer, don’t ever smoke. (33)
Visit here for helpful suggestions on how to quit smoking.
Alcohol consumption, particularly in excess, will also increase your chances of developing mouth, throat, esophagus, larynx, liver, and breast cancer. (34) While there is some information out that there may be beneficial substances in certain drinks, such as red wine, there is currently no hard-fast evidence that drinking red wine will help to cure cancer.
Limit your alcohol consumption to lower your risk of cancer, and when you do choose to drink, avoid high calorie sugary mixed drinks.
The best way to prevent cancer is to try to be the healthiest version of yourself while still living a full and enjoyable life. Knowing whether or not you are at a higher risk for developing cancer will help you to know what changes you need to make, how often you should be doing self check-ups, and how often you should be checked by your doctor.
It’s not too late to lower you and your family’s risk of cancer. Spread the word and help us make cancer a disease of the past.