We know what we need to do to reduce our risk of cancer, right? Wear SPF, quit smoking, avoid processed foods, exercise, lose weight and get enough sleep. But what if much of what causes cancer happened in our early years, or worse, before we were born? A recent study from Brigham and Women’s Hospital and Harvard University suggests this may be the case, particularly for cancers that appear before age 50 (early onset cancers).
The key finding of this study, published in Nature Reviews Clinical Oncology, is that people born after 1990 are more likely to develop cancer before the age of 50 than people born in 1970, for example healthcare, the economy and families.
What we are exposed to when we are young can affect our risk of developing cancer later in life, and this overview of cancer trends examines how these factors may affect early-stage cancers. Which stresses are important in early life is not yet fully understood, but frontrunners are diet, lifestyle, environment and the germs that live in our gut (the microbiome).
Looking at large numbers of people, researchers can find that diet and lifestyle habits are formed early in life. This is evident in obesity, where obese children are more likely to become obese adults. Because obesity is a known risk factor for cancer, these adults are more likely to develop cancer earlier, possibly because they have been exposed to the risk factor for a long time. Of course, some of these early-stage cancers are being caught through better screening programs and earlier diagnosis, contributing to the increasing number of cancers diagnosed each year worldwide. But that’s not the whole story.
Early-onset cancers have different genetic signatures compared to late-onset cancers and are more likely to have spread than cancers diagnosed later in life. This means that these cancers may need different types of treatment and a more personalized approach tailored to the patient’s age at the time the cancer develops.
Gut bacteria The Brigham study looked at 14 types of cancer and found that the genetic make-up of cancer, as well as the aggression and growth of the cancer, were different in patients who developed it before age 50 than in those who developed the same cancer after age 50 .
This appeared to be more pronounced in several types of colorectal cancer (colon, pancreas, and stomach). One possible reason for this lies in our diet and microbiome.
Gut bacteria are altered by high-sugar diets, antibiotics, and breastfeeding. And as the patterns of these things in society change over time, so do the bacteria in our gut. This could support the implementation of sugar taxes recommended by the World Health Organization. If our healthy cells are programmed in the womb, then so can the cells that cause cancer. Maternal diet, obesity and environmental pressures such as air pollution and pesticides are known to increase the risk of chronic diseases and cancer.
Conversely, severe restrictions on food intake during pregnancy, such as those observed during famine, increase the risk of breast cancer in the offspring. These two results would have different implications for societal approaches to cancer risk reduction.
As a hematologist, I care for patients with multiple myeloma, an incurable blood cancer that usually affects patients over the age of 70. In recent years, increasing numbers of younger people worldwide have been diagnosed with this type of cancer, only partly explained by better screening. This study identifies obesity as an important risk factor for early-onset disease, but there are clearly other risk factors that have yet to be uncovered.
Understanding what triggers early-stage cancer, what exposures are important, and what can be done to prevent them are some of the first steps in developing prevention strategies for future generations.
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)