There are 20 million new cancer cases and 9.7 million cancer related deaths worldwide per year. It is the 2nd leading cause of death and 1 in 5 people will develop cancer during their lifetime. Cancer is increasing worldwide and is predicted to continue to increase, most likely due to lifestyle related risk factors, and an ageing population. In the past 30 years there has also been a large increase in cancer diagnosed among younger patients (below 50) and these cancers tend to be more aggressive in nature. Advances in early detection of cancer, improvement in treatment protocols and the discovery of new therapeutic agents have dramatically increased the survival rates of some types of cancer.
As discussed previously the first step in our fight against cancer is cancer prevention - try not to get cancer. Based on current evidence, at least 40% of all cancer cases may be prevented.
In other words, there are modifiable risk factors such as obesity, alcohol and smoking, which we can control to reduce our risk of getting cancer. Secondly we must aim to catch cancer in its early, more treatable, stages - this is where cancer screening plays an important role.
For those who are diagnosed and living with cancer who are receiving the recommended medical treatment, there are important lifestyle modifications which may improve prognosis, improve quality of life during treatment, reduced risk of recurrence and overall survival after diagnosis. Evidence of the following recommendations come from studies which have looked at breast, colorectal and prostate cancers, although these recommendations can be used for all patients who are living with cancer.Â
Nutrition
A Mediterranean diet is associated with improved survival among breast and colorectal cancer survivors adherence to the Mediterranean diet was associated to lower risk of mortality in colorectal and prostate cancer survivors.
A healthy, nutritious diet is important for patient living with cancer who are undergoing treatment as well as after treatment. Cancer symptoms and treatment-related side effects are common problems which can contribute to malnutrition/ insufficient intake of food which can negatively impact quality of life, function and overall health. A nutritional assessment should be carried out as soon as possible after diagnosis to ensure adequate intake of nutrients such as protein in terms of both quality and quantity. In the longer term avoiding obesity and maintaining / gaining muscle mass is also important.
In general a healthy eating pattern is one which includes foods which are high in nutrients and which help maintain or achieve a healthy body weight. This should include a large variety of vegetables, whole fruits, fibre-rich legumes and whole grains. Red and processed meats, sugary drinks and ultra-processed foods should be avoided or minimised. Caution is advised with regard to dietary supplements during and after cancer treatment and it is always suggested to seek medical advice before taking supplements when on chemotherapy. In terms of ‘dietary patterns’ the Mediterranean and DASH diets encompass these recommendations.
Physical activity
Being as physically active as possible may have numerous benefits including the management of cancer diagnoses and treatment-related side effects. Following an individualised exercise program which is tailored to health and treatment-related symptoms, can help manage several aspects of quality of life during cancer treatment including anxiety, depression, and physical function in the short and long-term. It also helps reduce fatigue, get better sleep, maintain muscle and bone health. There may also be cancer-specific benefits, for example helping with lymphoedema experienced following breast cancer treatment.
Ideally patients would get a personalised assessment of their current fitness levels however the general guidance would be to be as physically active as possible and to incorporate both aerobic exercise and resistance training in a safe and appropriate manner. Being more physically active whilst being treated for cancer has been shown to improve treatment tolerance and response in certain cases. Increased levels of physical activity following diagnosis is associated with better cancer outcomes in breast, colorectal and prostate cancer survivors.Â
Obesity
Obesity is linked with a higher risk of developing various cancers including breast, colorectal, esophageal, kidney, gallbladder, uterine, pancreatic, and liver cancers. It has also been shown to worsen aspects of cancer survival including quality of life, cancer progression, cancer survival, and cancer recurrence. For example obesity is associated with an increased risk of treatment-related lymphoedema and a higher risk of recurrence in breast cancer survivors. In colorectal cancer, having higher visceral fat is associated with an increased risk of cancer recurrence and greater all-cause mortality.
Avoiding obesity refers to maintaining healthy body composition - that is having a relatively low percentage of body fat (in particular visceral fat) whilst having a good proportion of muscle mass (as such this is not always accurately represented through BMI, but it does serve as a good indicator). This is achieved through consistent adequate physical exercise and an healthy, balanced diet.Â
AlcoholÂ
Drinking alcohol is known to increase your risk of certain types of cancers, particularly when consumed in excessive amounts. Higher alcohol intake after being diagnosed with certain types of cancer, such as liver, head and neck cancer, is associated with worse outcomes. Although consistent evidence for other cancers is inconclusive as yet, the avoidance of alcohol consumption is recommended due to it being an established cause of several cancer types.
Tobacco smoking
Tobacco is a leading cause of many types of cancers including lung, mouth, throat, bladder, kidney, stomach, pancreas, cervix and colorectal. There is no safe level of tobacco use and someone who has never smoked has a better cancer prognosis than smokers or ex-smokers. Smoking cessation when diagnosed with cancer is very important. Smoking after a cancer diagnosis significantly impacts the mortality and morbidity of cancer survivors. It increases cancer recurrence, increases the risk of a second primary cancer, increases all-cause mortality and may also aggravate side effects of cancer treatment as well as deteriorate quality of life.
Lifestyle modifications following a cancer diagnosis are encouraged, particularly with regard to physical activity, healthy diet, smoking cessation, avoiding obesity and having low / no alcohol consumption. These lifestyle changes can be protective, improve quality of life and prognosis as well as having a positive influence on mental health and reducing side effects of treatment.
If you are a cancer survivor and would like have a personalised review of your lifestyle factores which can affect cancer outcomes, find out more about the Longevity Annual health check and download the longevity doctor guide to healthy living.