More and more evidence is emerging
Stress — especially chronic — is often cited as the cause of many diseases (and these are not only psychological problems, but also malfunctions of the cardiovascular, immune and many others body systems). However, what is poorly understood, but continues to cause increased interest among scientists, is whether stress can cause the development of cancer. Some researchers are convinced that this is a myth. However, new data suggests the opposite and does not exclude such a connection.
Over the years, doctors have often noted that difficult life events—loss, divorce, and serious trauma—often occur just before the onset of a serious cancer illness. That is, they actually become disease triggers.
However, the actual evidence is far from conclusive. Cancer Research UK (CRUK) claims that these links are not only unproven, but may be nothing more than a myth.
However, with stress levels rising and the number of cancer patients expected to rise by a third to four million by 2030, some cancer experts now say new evidence about the effects of stress on the body means it «wouldn't be surprising» for such a link.< /p>
Professor Melanie Flint, from the University of Brighton, who studies the effects of stress hormones on cancer, said: “There has been a lot of progress in this area and I don’t think we can rule out the influence of stress on cancer development. I think it does contribute to both the occurrence of cancer in the first place and the spread of cancer once it has been detected — but it is a contributing factor, not necessarily a direct cause.»
Some studies, in which have been observed in large populations over a long period of time seem to confirm this, writes the Daily Mail.
A study of 10,000 women in Finland over 15 years found that Bereaved survivors were more likely to develop breast cancer within five years.
Exposure to workplace stress is associated with an increased risk of prostate cancer in men under 65 years of age and, although the association is less pronounced, with a higher risk of breast cancer in women.
However, other similar studies including reviews of the highest quality evidence, do not demonstrate such an association.
According to Professor Trevor Graham, director of the Center for Evolution and Cancer at the Institute of Cancer Research, part of the problem is that stress often goes hand in hand with other behaviors that also increase the risk of developing cancer.
“ A stressful life can be associated with many other cancer risk factors, such as smoking, excessive alcohol consumption, inactivity and unhealthy diet, so it is difficult to isolate causal factors,” he explains.
We know that stress does cause a cascade of effects on the body, especially if it is chronic.
Professor Melanie Flint adds: “Stress causes the release of the stress hormone cortisol. It binds to receptors found in every cell, and this regulates various other processes, including inflammation. Stress and cortisol can also suppress the immune system.»
Scientists have also tried to reproduce the effects of stress on cells in the laboratory. This appears to indicate that stress damages DNA and causes changes in cells that, if allowed to proliferate, can develop into cancer.
However, since stress is difficult to model, this may not be the case a very accurate indicator of what is actually happening in the human body, says Professor Graham.
It is also likely that most people can reverse this damage naturally.
However, there is an exception: people with genetic mutations that already put them at higher risk of developing cancer may be less able to withstand the harmful effects of stress.
“If a person has a cancer mutation that affects the ability to repair DNA, they may be more vulnerable to the effects of stress. We can't say that if you're under a lot of stress and you have a cancer-causing mutation, you're going to get cancer. We still don't fully understand all the underlying mechanisms. But we may need to keep this in mind as a possible additional risk for some people, and stress may need to be managed,” warns Melanie Flint.
She adds that there is also some limited evidence that that stress may indirectly increase the risk of cancer by exacerbating viruses such as human papillomavirus (HPV), which is associated with cervical cancer.
The strongest evidence, however, suggests that stress may well play a role in the evolution of cancer after it has already developed.
Professor Nazanin Derakhshan, from the University of Reading, said: “Evidence shows that in breast cancer, anxiety and depression increase the risk of recurrence and mortality. More and more studies are reporting this, and we cannot ignore it.»
Professor Flint says cortisol may help cancer cells evade the immune system and spread from the original site of the tumor to a secondary site.
“If you are under stress and it lowers your immune system, or stress hormones affect the cancer cells themselves, then the cancer cells can hide from the immune system and, depending on the type of cancer, spread to more difficult to treat areas such as brain, lungs, bones and liver. While the evidence on whether stress can cause cancer may be unclear, it is much more clear that it can make existing cancer worse,” experts highlight.
Professor of Oncology Charles Swanton, Chief Medical Officer at CRUK, said: “Over the next five to ten years, we may see evidence emerging that tests the link between stress and cancer.”
But in the meantime, Professor Flint says, people who already have cancer or Those who have a genetic mutation that increases their risk should be given help to manage their stress levels.
This may include talk therapy, medication (strictly under medical supervision), exercise, or simply “self-care.” «—all of this will benefit you, whether you have cancer or not.
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