According to a recent study conducted in the United States, the number of adults under the age of 50 developing cancer has increased significantly worldwide over the past three decades. But isn’t this worrying increase due to improved screening techniques?
A disturbing development
Since the early 1990s, the world has faced a dramatic increase in cases of cancers before the age of 50. Researchers at the Harvard University School of Medicine (United States) have recently tried to understand whether or not this increase in the precocity of cancers constitutes a global emerging epidemic. According to this study published in the journal Nature Reviews Clinical Oncology on September 6, 2022, the answer is yes.
Due to the increase in population and progress in screening, it is not surprising to observe an increase in cases of cancer. On the other hand, what is more worrying is the fact that a greater number of people under the age of 50 are affected. The pathologist and epidemiologist Shuji Ogino who participated in the study is positive: the risk of early cancer seems to have increased with each new generation.
This conclusion comes from the risk analysis concerning 14 different types of cancer for people born between 1950 and 1990, as well as the study of risks from the 1990s. According to the results, there is a question of an evolution in the rate of cancer in people under 50 between 2000 and 2012 In addition, scientists have attempted to understand the factors of this evolution reviewing all previous studies on the subject.
A complex combination of factors
First of all, the increase in screenings detects a greater number of early cancers. On the other hand, this point is not the only one that can explain the phenomenon, and this is all the more true since there are countries that have no screening program but which today nevertheless face a rate of cancers unprecedented precocious. The leaders of the study also mention the change in lifestylesnotably the rise of ultra-processed foods.
To go further, the study suggests the implication of a complex combination between diet, lifestyle, environmental exposures and microbiome. However, the results show that 8 cancers out of the 14 analyzed are related to the digestive system. Furthermore, researchers became interested in sleep. While adults’ sleep duration hasn’t changed much in recent decades, children’s sleep duration has not. These latter sleep much less than before.
For scientists, a long-term objective should be set in order to reduce the risk of early cancers, namely educate people to lead healthier lives from the first years of their life.