A major new report from the World Cancer Research Fund has found strong evidence that obesity increases the risk of aggressive prostate cancer.
The WCRF, a not-for-profit organization that leads and unifies a network of cancer charities globally, is dedicated to prevention of cancer through diet, weight control, and physical activity.
The World Cancer Research Fund International/American Institute for Cancer Research Continuous Update Project Report: Diet, Nutrition, Physical Activity, and Prostate Cancer. 2014 is a meta-analysis that reviewed results from 104 studies involving more than nine million men (9,855,000 to be precise), with particular focus on diet, nutrition, physical activity, and weight as they relate to prostate cancer risk.
The study found strong evidence that being tall — a marker of developmental factors in the womb, childhood and adolescence — increases risk of prostate cancer, as well as limited evidence of linkage between diets high in dairy products or calcium and an increased risk of prostate cancer, and an association of low blood levels of vitamin E or selenium with increased cancer risk.
The World Cancer Research Fund International/American Institute for Cancer Research Continuous Update Project Report: Diet, Nutrition, Physical Activity, and Prostate Cancer. 2014, published in November 2014 as part of the WCRF’s Continuous Update Project (CUP) — the organization’s ongoing program of analyzing research worldwide on the relationship of diet, nutrition, physical activity and weight with cancer risk and survival — is heralded as “the most rigorous, systematic, global analysis of the scientific research currently available on diet, weight, physical activity and prostate cancer, and which of these factors increase or decrease the risk of developing the disease.”
The report can be downloaded in PDF format at:
According to the report, prostate cancer is the second most common cancer among males worldwide, and the most common cancer in men in 84 countries. Incidence is higher in developed countries, but rates have been creeping higher in the developing world as well. Thanks to the large proportion of prostate cancer cases of detected by screening — it is estimated that just over a decade hence prostate cancer will overtake lung cancer as the most common form of cancer affecting men worldwide.
Almost all prostate cancers are adenocarcinomas — a glandular malignancy. Roughly 1.1 million new cases were reported worldwide in 2012, accounting for 15 percent of all new cancer cases in men, although actual incidence of prostate cancer is suspected to be higher.
Early prostate cancer is usually asymptomatic, but detectable by screening. However, while prostate cancer can spread locally and metastasize and may be fatal, it may also remain latent without ever causing harm, and many men, especially at older ages, are found to have previously undetected and presumably asymptomatic
prostate cancers at autopsy. It’s been said that “more men die with it than of it.” In more advanced cases, men may experience weak or interrupted urine flow, inability to urinate, difficulty starting or stopping urine flow; and/or the need to urinate frequently, especially at night. Blood in the urine; or pain or burning with urination are also potential symptoms, although none of these symptoms are exclusively specific to prostate cancer and may also be caused by benign conditions such as prostatic hyperplasia (enlargement of the prostate).
The disease is more common as men age, and in the USA 97 percent of all prostate cancers are diagnosed in men 50 years or older — and with life expectancies increasing, more cases of the disease are probable.
One interesting phenomenon is that prostate cancer incidence rates vary more than 25x in different parts of the world. The highest rates are found in Australia, New Zealand, Northern and Western Europe, and North America – although part of disparity can be attributed to some countries employing screening methods that pick up large numbers of early cancers. Men with a family history of prostate cancer or who are of African heritage have greater risk of developing the disease. In the USA, for example, African American men are 1.6 times more likely to develop prostate cancer than Caucasians.
For the report, the data from global scientific research on diet, nutrition, physical activity and prostate cancer was analyzed by a research team at Imperial College London, and independently assessed by a panel of leading international scientists. The report updates the prostate cancer section of The
The researchers found strong evidence overweight or obesity (as assessed by body mass index (BMI), waist circumference and waist-hip ratio) increases advanced prostate cancer risk. There is also strong evidence that developmental factors that influence growth in the womb, in childhood, and during adolescence are associated with increased risk of developing prostate cancer, and that consuming beta-carotene (either in food or by taking supplements) is unlikely to have a substantial effect on the risk of prostate cancer. The findings on overweight and obesity, and adult height are new in this report.
Several specific recommendations are offered based on the study findings:
1) To reduce the risk of developing advanced prostate cancer, the WCRF recommends maintaining a healthy weight.
2) Following the WCEF’s Cancer Prevention Recommendations (available at wcrf.org), which include eating a healthy diet, being physically active and maintaining a healthy weight.
3) The WCRF concludes that better designed scientific research is needed to identify more clearly which tumors that are most likely to progress to advanced prostate cancer (helpful when analyzing risk factors for the disease).
General recommendations for cancer prevention
– Be as lean as possible without becoming underweight
– Be physically active for at least 30 minutes every day
Foods and drink that promote weight gain
– Limit consumption of energy-dense foods
– Eat more of a variety of vegetables, fruits, whole grains, & pulses such as beans
– Limit consumption of red meats (such as beef, pork and lamb) and avoid processed meats
– Limit alcoholic drinks
Preservation, processing, preparation
– Limit consumption of salt & avoid moldy grains and cereals
– Don’t use supplements to protect against cancer
– It is best for mothers to breastfeed exclusively for up to 6 months and then add other
liquids & foods
– After treatment, cancer survivors should follow the recommendations for cancer prevention
World Cancer Research Fund International