Dietary supplements were used by 40% of adult patients diagnosed and living with breast, prostate and colorectal cancer
Dietary supplements (DS) have been found to be used by 40% of adult patients diagnosed and living with either breast, prostate or colorectal cancer according to research by a team from the Department of Behavioural Science and Health, University College London, UK.
In recent years, survival from cancer is on the increase as reported by a 2018 global surveillance study which found that positive survival trends are evidence even among some of the more lethal cancers. Nevertheless, among those living with cancer, there is limited supportive evidence for strategies designed to reduce cancer risk although 2018 report by the World Cancer Research fund and the American Institute for Cancer research, was clear in its view on nutritional supplements, stating that ‘high-dose dietary supplements are not recommended for cancer prevention’ and encouraged individuals to obtain the required nutrients through diet alone. Despite this, some data indicates how cancer survivors report a higher usage of DS compared to those with the disease.
For the present study, the authors set out to gain a better understanding the range of and reasons for, use of DS among survivors of breast, prostate and colorectal cancer. They undertook a cross-sectional survey using data from the Advancing Survival Cancer Outcomes Trial (ASCOT) and asked respondents with each of the three cancers, their thoughts about lifestyle and cancer, use of specific foods, e.g. fruits, vegetables, meat and high calorie foods together with information on their use of any DS and other non-prescribed treatments such as herbal extracts. Respondents were asked to express their views (using a Likert scale) on the perceived importance of supplements as an approach to prevent cancer reoccurrence.
A total of 1049 participants with mean age of 64.4 years (62.1% female) provided usable data for analysis. Breast cancer was the most common (54.4%) condition, followed by prostate (25.2%) and colorectal (20.4%). In addition, the majority were of white ethnicity (94%) and 68% had either no (34.9%) or at least one co-morbidity.
In total, 40% of respondents reported DS use, of whom, 32% believed that these supplements were important for a reduction in cancer recurrence. The most commonly used form of supplements were fish oils (13.1%), followed by calcium and vitamin D (9.1%) and multivitamin and minerals (8.2%).
Using regression analysis, the only factors significantly associated with DS use were meeting the requirements for fruit and vegetable intake (odds ratio, OR = 1.36, 95% CI 1.02 – 1.82, p = 0.039), a belief in the importance of supplements to prevent cancer recurrence (OR = 3.13, 95% CI 2.35 – 4.18, p < 0.001) and the absence of obesity (OR = 0.58, 95% CI 0.38 – 0.87, p = 0.010).
The authors concluded that DS use among cancer survivors was common and influenced by patient’s beliefs about recurrence. They added that further work was required to better understand the reasons for such beliefs and how best to provide appropriate supplement advice to those living with a cancer diagnosis.