Six key lifestyle factors are driving the cancer epidemic in the United States, according to the American Association for Cancer Research's (AACR) 14th annual Cancer Progress Report.

American Association for Cancer Research. AACR Cancer Progress Report [2024].

The factors are modifiable, including reducing tobacco use, eating a healthy diet, being physically active, limiting exposure to UV radiation, reducing or eliminating boozy beverages, and preventing and treating cancer-causing pathogenic infections. 40% of all cancer cases in the US could be prevented with modifications to lifestyle, the AACR reports.

Transformative strides have been made in understanding and treating cancer, and, as a result, the cancer death rate is declining in the US. However, it is estimated that there will be over two million new cases of cancer (and over 611,000 deaths) in the US in 2024 alone. 

The AACR cites another alarming reality: About 84,100 adolescent and young adult (AYA) patients will be diagnosed with cancer in the US this year, making up 4.2% of all cancer diagnoses. Researchers think that genetic predisposition, infection with certain pathogens, diet, microbiome, excess body weight, and environmental exposures are the culprit.

American Association for Cancer Research. AACR Cancer Progress Report [2024].

A closer look at the lifestyle factors

• Smoking: The AACR says that over the past 30 years, smoke-free public health campaigns and policy initiatives have reduced the number of cancer mortality cases. E-cigarettes also put smokers at risk due to their toxic chemicals and metals. Patients should be urged to reduce or quit smoking.

  American Association for Cancer Research. AACR Cancer Progress Report [2024].

   

• Environmental exposures: Endocrine-disrupting and industrial chemicals can put workers at risk. People who are exposed to carcinogens and those who work night shifts are also at greater risk of developing certain types of cancer. Limiting exposure is key.

  American Association for Cancer Research. AACR Cancer Progress Report [2024].

   

• Obesity and lack of physical activity: Several cancer types are associated exclusively with obesity, while others are related to lack of movement. Many types of cancer are associated with both, including breast, stomach, kidney, liver, and colorectal cancer. The AACR recommends regular exercise, which can reduce the risk of nine different types of cancer. In people 18 and older, the recommendation is to get 150–300 minutes of moderate intensity exercise per week or 75–150 minutes of vigorous intensity exercise per week. Strength training should be done more than two times per week.

  American Association for Cancer Research. AACR Cancer Progress Report [2024].

   

• Alcohol: Drinking alcoholic beverages is associated with the risk of developing some head and neck cancers, esophageal squamous cell carcinoma, and breast, colorectal, liver, and stomach cancers. Physicians should know that counseling in a primary care environment may help patients cut back on drinking. Moderate drinking means one or fewer drinks per day for women and under two or fewer per day for men. This doesn’t mean that patients can save all their drinks for a single day, since three drinks or more for women and four drinks or more for men on any day is considered “heavy drinking.”

  American Association for Cancer Research. AACR Cancer Progress Report [2024].

   

• UV radiation: Ultraviolet radiation is the cause of 95% of skin melanomas (4.6% of all cancers). Sunburn also increases the risk of cancer, so beachgoing patients should be advised to stay safe By limiting sun exposure between 10 a.m. and 4 p.m.; covering arms and legs; wearing sunscreen that is SPF 30 or higher; and avoiding UV tanning devices.

  American Association for Cancer Research. AACR Cancer Progress Report [2024].

   

• Pathogens: Certain kinds of pathogens can compromise the immune system and drive inflammation, leading to cancer. Pathogens like  human papillomavirus, hepatitis B, hepatitis C, and Helicobacter pylori account for 3.4% of all cancer cases. For example, Helicobacter pylori is responsible for 810,000 cancer cases, including stomach cancer and non-Hodgkin lymphoma. Patients should practice good hygiene and sanitation, get vaccinated against HPV, and avoid behaviors that can lead to hepatitis B and C infections. 

  American Association for Cancer Research. AACR Cancer Progress Report [2024].

   

“It’s more important than ever for family and internal medicine physicians to begin conversations with younger patients about cancer screenings well before they are of the recommended screening age,” Mohammed Najeeb Al Hallak, MD, MS, an oncologist and member of the gastrointestinal multidisciplinary team at Karmanos Cancer Institute, tells MDLinx. 

He says that it’s especially important to discuss cancer risk with patients of certain ethnic groups. “Black people in the US develop colorectal cancer at higher rates, get it earlier, and have worse outcomes,” he adds. Patients should be screened for cancer as soon as they are eligible, or earlier, depending on family or biological circumstances.