Up to 80% of cancer patients unintentionally lose weight which can have a devastating impact on their quality of life reducing their ability to tolerate chemotherapy and leading to poor survival rates according to Dr Aoife Ryan, dietitian and lecturer in Nutritional Sciences at UCC.
The seriousness of this issue is illustrated by the fact that one in five cancer deaths are caused from wasting, not from cancer. The wastage affects not just the muscles involved in movement but also the muscles involved in breathing and in the heart. Dr Ryan says, unfortunately, there is no safe drug to prevent or reverse this or to safely stimulate appetite.
“It seems it is almost the norm to lose weight once you develop cancer. Ten years ago it was thought patients were losing fat. Now we can use their CT scans to measure exactly what patients are losing and we are gaining a huge understanding that that weight loss is actually muscle. It is rapid loss of muscle.”
A great example of how the roles of nutritionists and food scientists can help cancer patients can be seen from current research at UCC into the development of innovative protein gels, dietary drinks and appetite-increasing supplements to assist cancer patients who are experiencing involuntary and at times life-threatening weight loss.
Cancer patients often develop severe muscle wasting called ‘sarcopenia’ which is most commonly seen in very elderly people and is an inevitable consequence of growing very old.
Dr Ryan’s team of nutritional scientists at UCC have performed a detailed study of the nutritional status and quality of life in ambulatory Irish cancer patients attending for chemotherapy at Cork University Hospital and the Mercy University Hospital. In a study which has been on-going since 2011, 1,020 patients have been recruited to date.
“We have looked at over a thousand patients having chemotherapy here in Cork and only 4% of them look underweight. We rarely see obviously wasted cancer patients anymore, nowadays they look normal or overweight but, underneath that fat, there is very little muscle. Over 40% have sarcopenia and these patients live about half as long as people who maintain their muscle.” It is known that protein intake is of fundamental importance in this regard, and so she is looking at ways to increase this intake and also to address why patients are losing weight in the first place.
“They are losing weight because cancer causes huge amounts of inflammation in their bodies. So can we dampen down inflammation which would cause them to stop losing weight? If they are weight stable they will live longer.”
Towards this goal, Dr Ryan has spent over 12 years studying the fish oil, EPA, which is found in salmon, mackerel and herring. Unfortunately, most people eat very little of it. To provide new means of incorporating EPA into the diet, nutritionists at UCC have joined forces with food scientists to put a high dose of fish oil into a nutritional drink. Dr Ryan says the results to date have been encouraging.
“Several clinical trials have shown that, if we give patients with cancer calories, protein and a very high dose of a fish oil, that it will dampen down inflammation and they will lose less muscle. Keeping patients active through exercise is also hugely important.”
As part of this work, Dr Ryan develops products in conjunction with colleagues including Dr Shane Crowley and Professor Alan Kelly of the School of Food and Nutritional Sciences at UCC. Professor Kelly says this work is a perfect example of where a complementary relationship between Nutrition and Food Science can deliver hugely important outcomes.
“Food Scientists have the skills to develop products the design of which has been informed by the nutritional understanding of what food does to the body and, in this case, the particular issues of cancer patients are that we hope to solve. But there might be other considerations to do with the texture or the structure, for example in terms of chewing and swallowing and digestibility or flavour. So the food scientist says “How do we design that product? How do we mask flavour? Any product is ingredients plus a process we apply to it, so food scientists will find the right ingredients for the product properties that are needed and work out a way to turn these into a desirable, safe and high-quality product.”
Meanwhile, food scientists at UCC are also developing high protein gels for cancer patients, based on the fact that patients undergoing chemotherapy often suffer from metallic tastes in their mouths so they have taste challenges as well as appetite challenges. The gels would be tasteless and could be added into food without affecting texture and yet deliver critical nutrients and taste sensations tailored to the sensory perceptions of cancer patients.
Scientists at UCC working as part of the national Food for Health Ireland consortium have also found small peptides, released from proteins from milk that can mimic the action of hunger hormones in the body. Initial studies in animals conducted at UCC showed increased food intake when given these peptides.