Dec. 20 (UPI) — One in five adults in remission from cancer believe that dietary supplements reduce the risk for the disease returning, a study published Monday by the journal Cancer found.
Among the cancer patients in the study, 13% reported using fish oils, making them the most commonly used dietary supplements for those with the disease, the data showed.
However, 15% of people with breast cancer specifically said they used calcium supplements with or without vitamin D, the researchers said.
“We found one in five people who had been treated for cancer mistakenly thought that taking vitamins or other supplements would help reduce the risk of their cancer coming back,” study co-author Rana Conway said in a press release.
In addition, “those who believed supplements were important for reducing their risk of cancer recurrence were three times more likely to take them,” said Conway, a research fellow in nutrition at University College London in England.
For this study, Conway and her colleagues assessed supplement use among 1,049 survivors of breast, prostate or colorectal cancers in Britain.
Study participants completed a mailed survey and telephone or online dietary analyses that included questions on dietary supplements, the researchers said.
Dietary supplements are more strictly regulated in Britain than they are in the United States, and those on the market are required to meet stringent ingredient labeling standards, they said.
About 40% of cancer patients in the study indicated that they used dietary supplements, which are manufactured products that typically come in pill, capsule, tablet, powder or liquid form, according to the National Library of Medicine.
They are designed to provide nutrients, which are either extracted from food sources or developed synthetically, to increase the quantity of consumption, it says.
Women, participants who reported that they met recommendations for fruit and vegetable consumption — about five servings per day — were up to three times more likely to use dietary supplements, the data showed.
Similarly, those who believed that dietary supplements were important for reducing the risk for cancer recurrence were also up to three times more likely to use them, the researchers said.
Conversely, participants who were obese, or severely overweight, were less likely to use dietary supplements, according to the researchers.
Based on the findings, healthcare professionals need to provide advice and clarity to patients about the appropriate use of dietary supplements, Conway and her colleagues said.
Current guidelines for cancer prevention from the Centers for Disease Control and Prevention and the National Cancer Institute, among others, recommend a healthy diet and physical activity to lower risk for the disease.
However, they do not recommend dietary supplements, as studies have generally failed to show a benefit associated with the products, the researchers said.
There are also some indications that these supplements may actually harm people recovering from cancer by interfering with how their prescribed treatments work, they said, although studies have found that vitamin D, for example, reduces the risk for cancer spread.
“As the number of people living with or beyond cancer increases, there is a growing need for a more holistic approach to long-term healthcare,” Conway said.
“Information about the role of supplements and the lack of evidence that they reduce cancer recurrence would be beneficial, alongside discussions about the benefits of healthy eating and physical activity,” she said.