The young person’s guide to reducing cancer risk

Unless you have a family history or a higher personal risk, cancer might not really be on your radar when you’re younger. And yet — maybe it should be. Statistics show that about two in five people will develop cancer in their lifetime. Things are looking up though — the overall cancer mortality rate has continued to decline due to lower rates of smoking, earlier cancer detection, and better treatment. 

But those gains may be thwarted for certain groups of people. A 2025 research article in Cancer Discovery analyzing data from 2010 to 2022 found that incidence rates of 14 cancers increased among adults under age 50. This is especially true for women under 50, who have a higher risk of developing cancer compared to men of the same age group. Globally, the rate for “ early-onset cancer ” (cancer diagnosed in people younger than 50) has risen by nearly 80 percent, with mortality from cancer increasing 28 percent in that group. 

But you have some power here: Around 40% of certain cancers could potentially be avoided. And while some factors, like genetics, aren’t in our control, some are — including how active you are, your diet, and alcohol use. Here’s what experts want you to know (and do) to live a healthier life, now and later.

Having a weight in the overweight or obese category is linked to an increased risk of 12 cancers in the U.S., according to a new review in JAMA. They include endometrial, esophageal, gastric, kidney, colorectal, liver, gallbladder, pancreas, prostate, post-menopausal breast, ovarian, and thyroid cancers. Obesity and overweight accounts for about 10% of new cancer diagnoses, the research also points out.

That’s because higher weight usually means more body fat. “Excess fat mass causes increased levels of inflammation and metabolic dysfunction, which are associated with cancer,” says Tracy E. Crane, Ph.D., RDN, director of lifestyle medicine, prevention and digital health at the Sylvester Comprehensive Cancer Center at the Miller School of Medicine, University of Miami. 

Weight doesn’t tell the whole story, though. So, if you have an opportunity to get your body composition measured, Crane recommends doing it, as it will reveal how much fat your body carries versus your lean mass. You can even do this through the WW app, which now has an AI body scanner feature. 

A good goal? Increasing muscle mass while decreasing fat. “Even if the scale doesn’t budge but your body composition changes, your metabolic function and inflammation levels will improve,” Crane says. You don’t need to do this on your own: Our Weight Watchers Programs can help you prioritize a healthy diet and physical activity.

Alcohol is a known carcinogen — a substance that can cause cancer. It damages DNA, causes chronic inflammation, and increases hormones like estrogen, which can raise your risk of breast cancer. And this holds true for even moderate amounts of alcohol. “There is no level of alcohol that conveys health benefits,” says Crane. “And some trials show an increased risk for women when consumed at any level.” 

The decision on whether or not to drink is your own, of course. Knowing the info on alcohol and cancer risk, will allow you to choose what’s right for you. “Infrequent drinking — or not at all — is probably the best advice,” says Crane.

As for smoking, you’re best off not touching tobacco full stop. But if you currently smoke, you can reduce your risk of developing cancer by quitting — and the sooner the better.

Ultra-processed foods (UPFs) — fast food, packaged snacks and desserts, processed meats, sugary beverages, frozen pizzas — make up over half of the average American diet. And that’s not great for your health. “These are increasingly being identified as contributing factors to overall cancer risk, particularly colorectal cancer among younger individuals,” says Meghan Garrity, M.S., RDN, a registered dietitian specializing in oncology nutrition in New York City. “Consuming ultra-processed foods that are high in refined grains, added sugars, sodium, and saturated fats on a daily basis not only increases total body inflammation, but replaces the nutrient-rich whole foods that have shown to be cancer-protective,” she says. 

For instance, UPFs often are lower in dietary fiber, an important nutrient in reducing cancer risk that’s found in many whole foods. “Fiber, which is found in plant foods including fruits, vegetables, whole grains, beans/legumes, and nuts and seeds, feeds the healthy bacteria that live in our gut, often referred to as our gut microbiome,” explains Garrity. When your gut bacteria feeds on fiber, they produce short-chain fatty acids (SCFAs) in the colon, helping to reduce inflammation, regulate the immune system, and support a healthy gut lining, she says. 

In addition, the vitamins, minerals, and phytonutrients in foods like fruits and vegetables provide antioxidant protection against DNA damage to healthy cells (something that can lead to the development of cancer). You don’t need to shun all processed foods, but any progress you can make to replace UPFs with whole foods can help you move in the right direction.

All you’ve heard about the health benefits of having an active lifestyle is true. Data suggests that some activity every day makes a difference in lowering cancer risk for obesity-related cancers like breast cancer. Exercise helps maintain a healthy weight, builds lean tissue like muscle and reduces fat mass, supports immune system health, and reduces chronic inflammation.

The American Institute for Cancer Research, along with other major health organizations, recommends doing moderate intensity activity 150 minutes per week (or doing it for about 30 minutes, five days per week). But within those recommendations is a lot of wiggle room. “My advice is to participate in activities that you enjoy, whether that’s kayaking, yoga, weight lifting, hiking, or running,” says Crane. She also recommends pairing up with a friend. “There’s so much positive that can come out of exercising socially. People report more enjoyment and are more likely to stick with it.”

And don’t forget about resistance exercise, which is especially important as you age and muscle mass naturally begins to decline. “Muscle regulates a lot of things, such as metabolic health, which is related to obesity and diabetes, two risk factors for cancer,” says Sami Mansfield, ACSM-CET, co-author of the ASCO Guideline on Exercise, Diet, and Weight Management During Cancer Treatment and founder of Cancer Wellness for Life. “Having more muscle creates a less hospitable environment for cancer.”

Sleep sets the stage for other healthy habits. Being well-rested can make it easier to exercise and prioritize healthy food. And it works both ways: Being active can help you sleep better (as long as you don’t do it too close to bedtime). This can all be tied to reducing your risk for cancer. While the science isn’t definitive, there is some evidence that chronic poor sleep may be connected to the increased risk of the development of cancer. Sleep conditions — insomnia, sleep apnea — are linked to higher levels of inflammation, which may affect the immune system’s ability to detect and fight off cancer in the first place. “I recommend going to bed and waking up at the same time each day,” says Crane. In addition, go outside in the morning — exposure to natural light helps to regulate your circadian rhythm (“body clock”), so it’s easier to fall asleep at night.

Talk to your family members about your family history of cancer. While not every cancer has a genetic component, having close family members with certain cancers like breast and ovarian cancer can raise your own risk.

It may not be exactly holiday or BBQ fodder, but the Centers for Disease Control and Prevention recommends using family gatherings as a time to discuss health history; they also recommend a tool called My Family Health Portrait to keep track of it all. 

That information can help guide your next steps. “For family history of some cancers, you may be able to look into genetic testing to better understand your personal risk,” says Crane. And depending on what the results show, you can then talk to your doctor about proactive steps you can take or recommended screenings.

Routine screenings and vaccines are two important steps in reducing your risk for cancer. Currently, there are two vaccines to make sure you’re caught up on:

• Human papillomavirus (HPV): This vaccine protects against the HPV virus, which raises the risk of cervical, head and neck, anal, penile, vaginal, and vulvar cancer. Guidelines recommend starting HPV vaccination at ages 11 to 12, though people who are under age 26 are still eligible. If you are ages 27 to 45, you may still benefit, so talk with your doctor about whether it makes sense for you.

• Hepatitis B: This helps protect against chronic hep B infection, which can cause liver cancer. The vaccine is given soon after birth and in early infancy, and it is believed to offer lifetime protection. Adults can also get vaccinated — talk to your doctor if you’re concerned about your hep B risk or weren’t vaccinated when younger. 
  

For risk reduction and possible prevention, make sure you get colonoscopies on schedule. These procedures don’t just look for cancer, but the doctor can remove potentially precancerous polyps (growths) that could become cancer down the road. This should happen starting at age 45 (earlier if you have certain risk factors, such as inflammatory bowel disease, a family history of colorectal cancer, or certain genetic syndromes). This is on top of getting any other recommended cancer screenings, like mammograms, pap smears, and skin cancer checks.

Although cancer incidence is rising for many cancers, especially when it comes to adults under 50, there are many lifestyle habits that you can do now to reduce your risk. Those include reducing ultra-processed foods in your diet, eating more fiber-rich plant foods, staying physically active, getting good sleep, reducing or eliminating alcohol (and avoiding smoking), and getting proper screening and other preventative care with your doctor. “These are all factors that people have control over and that can make an impact at any age,” says Crane. And Weight Watchers Core Program can help you turn these healthy habits into a lifestyle, with expert help — including appointments with a registered dietitian — and a community to help keep you on track.