Health experts say that it is time to properly discern between proven and unproven theoretical models. These models could mislead not only patients but also health care practitioners in properly diagnosing diseases.
For many years, many believed that X-rays, CT scans and other imaging tests could cause cancer. Researchers now conclude there is no evidence that low-level radiation from medical imaging causes cancer.
In a study published in the American Journal of Clinical Oncology, the researchers debunked the widespread and old belief about medical imaging. They say that linear no-threshold (LNT) is an unproven theoretical model. The risk revealed by the model is only based on theoretical assumptions and was not proven by evidence.
LNT is a model used to estimate cancer risks form low-dose radiation procedures that are widely used in the medical practice.
The researchers added that the utilization of the LNT model leads to unfounded fears and unimportant costs wasted on safety measures which are deemed unnecessary. Dr. James Welsh, a radiation oncologist at the Loyola University Medical Center says that the LNT model hinders many doctors from using imaging procedures on patients. It also discourages patients from getting appropriate and necessary diagnostic procedures just as to avoid radiation exposures.
To land to their findings, the researchers re-studied original researches that led to the development of the LNT model and its application to current medicine. The studies, which can be traced to about 70 years ago, show no evidence to support such model.
According to the LNT model, there are no such safe levels of radiation, no matter how small the dose is. The researchers, however, said that the human body has evolved throughout time and it has now the ability to repair the damage caused by low-dose radiation, which is present in the environment.
In the '40s, where the study that supported LNT was conducted, researchers tested many doses of radiation on fruit flies. They found that there is no safe level of radiation that contributed to the birth of the LNT model. The experiments, however, did not include really low doses, which were not tested on fruit flies until 2009. The results show no evidence to support the currently used, decades-long model.
The study authors concluded that the LNT should not be used at present since it stirs unfounded fears among patients and health practitioners. Imaging techniques are very effective in diagnosing various diseases including cancer and the fear of radiation even at very minimal doses wastes time in early treatment of illness.
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