Beware of Sudden Weight Loss

A recent study has revealed that individuals who have unintentionally lost more than 10% of their weight over the past two years may have an increased risk of upper gastrointestinal cancer and other cancers.

A team led by Dr. Brian Wolpin at the Dana-Farber Cancer Institute (DFCI) in the U.S. announced the results of a study that tracked over 157,000 healthcare professionals for up to 38 years, in the Journal of the American Medical Association (JAMA) on the 24th.

According to the study, those who unintentionally lost more than 10% of their weight had a significantly higher risk of being diagnosed with cancer within a year.

In this study, the research team tracked 157,474 participants from two large longitudinal studies: the Nurses’ Health Study, which started in 1976 and targeted nurses aged 30-55, and the Health Professionals Follow-up Study, which began in 1986 and targeted male healthcare professionals aged 40-75. The observations continued until 2016.

Participants reported their weight every two years through a questionnaire that included questions about physical activity and answered questions about dietary changes every four years. Based on the diet and physical activity information, the research team categorized the participants’ weight loss behaviors into ‘high, medium, low’ groups.

During the tracking observation over a total of 1.64 million person-years (one person-year is the value of observing one person for one year), a total of 15,809 cases of cancer occurred (964 cases per 100,000 person-years).

The number of people who lost more than 10% of their weight in the last two years and were diagnosed with cancer within 12 months was 1,362 per 100,000 person-years, which is 493 more cases per 100,000 person-years than those who did not lose weight.

In particular, the number of cancer cases among participants who lost more than 10% of their weight without intending to do so was 2,687 per 100,000 person-years, more than double the number of cancer cases among participants who did not lose weight (1,220 cases per 100,000 person-years).

Among the cancers, upper gastrointestinal cancers such as the esophagus, stomach, liver, bile duct, and pancreas were more common among participants who lost more than 10% of their weight – 173 cases per 100,000 person-years, nearly five times higher than those who did not lose weight (35 cases per 100,000 person-years).

Dr. Wolpin advised, “Unexpected weight loss can occur due to cancer or other various diseases. While losing weight due to exercise or a healthy diet can be beneficial for health, in the case of unintentional weight loss, it would be advisable to consult with a doctor to determine whether tests for cancer or other causes are necessary.”

By. Soo Jung Shin