A Vox reader asked: What Happened Between Gen X and Millennials to Increase Cancer Rates?
That is the million dollar question in medical science today.
You’ve surely seen the headlines, but let’s recap the most relevant facts: One in five new colorectal cancer patients in the U.S. is under the age of 55, Wall Street Journal Analysis Data from the National Cancer Institute. This is almost double the 1995 rate. A recent meta-analysis led by the American Cancer Society found that 17 of the 34 most common cancers — including the small intestine, pancreas and kidney — occurring more frequently in younger people. Some of them had declined earlier but are now rising again.
Here’s the really scary part: While death rates for colorectal cancer patients over age 65 are decreasing, they are increasing among younger patients. Scientists say this is primary cancer It can be more serious because they are often not caught until it is too late to seek treatment. (Colonoscopy is not recommended until age 45.)
As a millennial prone to health concerns, I have the same question: Why is this happening to my generation? Unfortunately, the short answer is: we don’t know for sure. But let’s dig into the long answer.
What do we really know about cancer risk factors?
We have known this for a long time Weight and exercise Helps determine a person’s risk of developing it A range of cancers. increase in Global obesity rates Since the mid-1990s it has probably played a significant role in the increase in early-onset cancers, particularly those in the gastrointestinal tract.
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But over the past decade, new research has shown that other factors — certain foods in the diet, other behaviors such as sleep, environmental pollutants — may also contribute to cancer risk. These risk factors are not as well understood as obesity or lack of exercise, but scientists are now racing to catch up.
Scientists have found that certain foods, including foods rich in so-called ultra-processed foods connected Regardless of a person’s BMI, those with a higher risk of GI cancer. Higher alcohol consumption is the same related Early colorectal cancer risk is high. exposure toxin Chemicals found in makeup and hair products and formaldehyde in building materials in the environment and in everyday products are now also suspected of increasing the risk of a wide range of cancers in young patients, especially if the exposure occurs at key points in a person’s life. Poor sleep or disturbed sleep It can also be a factor in the development of breast, colon, ovarian and prostate cancer.
“Sleep and circadian rhythms are an important component of health,” Andrew Chan, who leads an international research project on early-stage cancer, told me. People today “probably getting less sleep or sleep disturbances for various reasons. Is it potentially changing our biology in a way that is harmful?”
Cancer researchers are also obsessed with the microbiome, the ecosystem of bacteria that is concentrated in a person’s gut. specific type The microbiome is associated with bacteria GI cancer development, but researchers are still confused as to whether these changes are the cause or consequence of the disease.
This is truly a global challenge. The increase in early cancer cases and death is most pronounced in rich countries, but developing countries are struggling with the same environmental pollutants, especially MicroplasticsAnd they are already increasing the death rate from others Obesity related diseases. As poor countries become more economically developed, they will see more “first world” health problems — including cancer.
“This is going to be an issue that we’re going to face as our economy gets stronger,” Bhavna Sirohi, director of medical oncology at Balco Medical Center in Raipur, India, told me earlier this year. It “faces us, west, everywhere.”
Why do different generations have different cancer risks?
Since I started reporting on this slow-rolling crisis at the beginning of the year, one of the most interesting things I’ve learned is that your risk for many types of cancer probably depends on something completely out of your control: when you were born.
If you go back to the American Cancer Society’s meta-analysis, people born in 1975 have almost twice the rate of small-bowel cancer as people born in 1955. For people born in 1990, the rate of this cancer increased almost four times. was for those born in the mid-20th century. You can see the same general trajectory for kidney, liver, pancreas and bone marrow cancers.
These generational differences would support the increasingly accepted idea that recent environmental changes and sweeping changes in our diet may contribute to the rise of early-onset cancers. A 2020 study in the journal Gastroenterology Note that A person’s risk of GI cancer was previously measured by their family history, yet three out of four new cancer patients have no such history. The researchers concluded that the surge may instead be the result of “generational differences in diet, environmental exposures and lifestyle factors.”
A systematic review of available studies published Frontiers in nutrition In 2022Many identified risk factors for deep-fried foods, processed foods, fatty foods, and sugary drinks and sweets, as well as low folate and fiber consumption. has been human Eating more and more of those products over the years — well, except for fiber, which is great for human digestion and still woefully under-consumed in the US. my generation Drinking too much alcohol Even as evidence of its carcinogenic properties continues to accumulate.
Scientists hypothesize that changes in our environment, such as the proliferation of microplastics and the ever-present chemicals associated with them Certain cancers And maybe Allow others to metastasize more easilyThere may be other contributing factors. From food containers to synthetic garments, we These tiny particles are exposed to and ingested every day.
According to a Paper published last year According to a New Zealand research team, the rise in cancer among young adults matches the timeline we would expect from the multiplication of microplastics in the environment. Studies have been conducted in cellular and rodent models Recommended That microplastics can promote tumor growth. Although more research is needed, we already know these materials retention Chemicals that can disrupt hormones and pose risks to our health.
In the same vein, scientists are increasingly suspecting that exposure to risk factors at certain ages — whether in utero, during childhood or early adulthood — may play an important role in a person’s risk of developing cancer at a young age. Primary results, such as a Study Drinking more sugary drinks during adolescence was associated with an increased risk of developing colorectal cancer in women, supporting these theories.
Researchers are working to sharpen our understanding of these factors and how to treat and prevent these devastating diseases. We still have a lot to learn about these new variables in our cancer risk. Although it’s easy to feel powerless in the face of that uncertainty, all the long-sense recommendations still apply and can make a difference to our health and disease risk: we can try to eat right, drink less alcohol, and be more active.