Nutrition is particularly important for those undergoing cancer treatment, but new research suggests that many such patients receive little or no information.
A study by doctors at Madrid's Hospital Universitario de la Paz found that only one third of cancer patients are given information about the importance of diet, which can influence their chances of survival.
Study author Carmen Gomez Candela, head of the clinical and dietetics department at the hospital, commented: "It is essential that we know about cancer patients' opinions so that nutritional therapy alternatives can be found to improve their quality of life and sense of wellbeing in general."
The researchers interviewed 131 patients and found that, although more than half had experienced eating difficulties, only a third had been spoken to about their diet.
Dr Gomez Candela added that many patients wanted to receive nutritional education so that they knew which foods to eat and in what quantities.
According to Cancer Research UK, more than one in three people will develop some form of cancer during their lifetime.
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