We’ve been repeatedly told the gospel of exercise, but researchers are now suspecting a molecule released during heavy exercise may be helping cancer cells form. Lactate may be converting healthy cells into cancerous ones, scientists say.
When we exercise, sugars are broken down into smaller components in a process known as glycolysis. One of these smaller byproduct molecules is lactate. Heavy exercise causes the accumulation of lactate in the blood and muscles, leading to oxygen debt and fatigue.
This process of oxygen deprivation and lactate accumulation is similar to what happens in some cancer cells. In fact, this very phenomenon was described in 1923 by Otto Warburg, who observed that cancer cells consumed more glucose and had more lactate buildup than normal cells. The phenomenon has since been dubbed the “Warburg effect.”
Does lactate have a role in oncogenesis – the process by which healthy cells get sick and turn into cancer cells? If so, how does lactate benefit cancer? Scientists at the University of Colorado-Boulder's Sports Medicine and Performance Center decided to revisit cancer’s metabolism.
The authors suggest that “lactate is probably the only metabolic compound involved and necessary” in carcinogenesis. This includes “angiogenesis immune escape, cell migration, metastasis and self-sufficient metabolism.”
But how do the conclusions and hypotheses about lactate fit with the gospels about exercise? The authors suggest that people who exercise regularly have adapted to better prevent and process lactate buildup. By contrast, lactate may accumulate easier in sedentary people, which may explain the higher cancer risks.
"With this paper, we open a whole new door for understanding cancer, showing for the first time that lactate is not only present, but mandatory for every step in its development,” said Inigo San Millan, the study’s first author. "We hope to sound the alarm for the research community that to stop cancer you have to stop lactate," he says.
Additional sources: MNT