Nutrition, diet and prostate cancer
By Kalli Spencer
Many hypotheses have been tested to find the cause of prostate cancer. Much research has focused on various nutrients and diets as a potential risk factor. This blog will provide a brief update on contemporary research findings, discuss the concept of pre-adaptation, and conclude with integrative clinical models to improve diet and nutrition for patients at different stages of their cancer journey.
Animal studies have shown that certain nutrients including fats, proteins, carbohydrates, vitamins and polyphenols lead to the formation or prevention of cancer through various pathways related to the effects of antioxidants, inflammation and sex hormones. Conflicting study results have made it increasingly difficult to determine which nutrients cause prostate cancer or allow it to grow and spread. This may be due to the weak effect of a single nutrient or an interaction between different nutrients. A diet high in saturated fat (animal meat and butter) is believed to increase local androgens (testosterone) and trigger other immune mechanisms (eg, macrophage infiltration, GF-I signaling pathways). Obesity may be an independent predictor of prostate cancer and may also lead to progression to advanced cancer. High calorie diets can cause chronic systemic inflammation and trigger cancer growth through mechanisms related to the immune system. Several studies have shown that protein intake has not been linked to prostate cancer while carbohydrates may increase the risk. Some vitamins have shown a decreased risk such as lycopene (Vitamin A) present in the skin of tomatoes which has an antioxidant effect and decreases androgen metabolism. Calcitriol or the active form of vitamin D (found in dairy products, fish, mushrooms) reduces risk by promoting the differentiation of immune cells. The benefits of vitamin E are still questionable, but may include antioxidant and anti-inflammatory effects. Polyphenols such as catechin found in green tea are believed to decrease risk via the IGF-I signaling pathway and anti-inflammatory effects mediated by COX-2. These studies were performed with participants of different diets. It is therefore necessary to study dietary patterns focusing on the summative effect of the intake of nutrients from similar origins. Some researchers believe that a “Western model” rich in dairy products, meat, potatoes may increase the risk compared to a “conservative model” (fruits and vegetables, legumes and fish) which decreases the risk. This healthier diet (eg, lots of vegetables with reduced meat consumption) is believed to help prevent prostate cancer and lifestyle-related diseases; however, there is insufficient substantial reliable evidence.
Another area of research is the effect of gut microbiota diversity on nutrition and diet. It is believed that there is an interaction between the gut microbiota and nutrients, where nutrients alter the composition of the gut microbiota, affecting metabolic pathways and / or nutrient absorption. The authors of a Japanese study proposed the concept of a “microbiota-gut-prostate axis” where although the prostate is not directly affected by gut bacteria, it could be indirectly affected by cytokines and modified immune cells. by said bacteria and absorbed by the intestine. into the systemic circulation to reach the prostate1. The authors also believe that environmental factors might play a role, as Japanese people who migrated have an increased incidence of prostate cancer compared to Japanese residents in Japan.
Results from the MARTINI lifestyle cohort show that adherence to a dedicated intervention program prior to radical prostatectomy is low, with none of the participants achieving all of the goals.2. Through the use of a validated questionnaire used for the European Prospective Investigation into Cancer and Nutrition (EPIC) study, it was found that 75.4% of all participants did not meet the recommended meat intake. , 88.8% reported a low intake of fruits and vegetables, and 86% did not meet the recommended fiber intake. Proper diet and proper nutrition are important during pre-adaptation which is “a process of physical and psychological assessments performed to establish baseline functioning and identify impairments that may impact cancer treatment, associated morbidity and provide guidance. targeted interventions to optimize general well-being before treatment ”. This allows for a faster recovery time and general well-being after treatment. Changing the diet has been shown to reduce the intestinal side effects of prostate cancer treatment, maintain a proper body mass index, and improve the quality of life for some men. A team of oncology nurses from the University of Canberra have developed a model of prostate cancer that incorporates nutrition as they believe it is often overlooked by healthcare professionals3. Good post-treatment nutrition is recommended as an evidence-based survival intervention as part of the essentials of prostate cancer survival4. The benefit of nutrition in advanced cancers and those on androgen deprivation therapy is beyond the scope of this blog.
The Prostate Cancer Foundation of Australia operates a supportive telephone care service run by clinical nurse specialists. ProsCare helps with decision support after diagnosis; treatment education with self-management and skills training for symptom effects, including exercise prescription and dietary counseling; and communication with various health care providers (such as dietitians)5. The centralized service addresses some of the unmet needs of people with prostate cancer, such as physical, emotional, psychological, privacy and information needs.6. Some of the advantages of nurse-led service are that they provide care in a flexible manner; identify actions to reduce risks; facilitate rapid readmission to acute services, if necessary; manage side effects of treatment to avoid hospitalization; free up consultant time; and patient empowerment7.
Mount Sinai Hospital in the United States has developed a prostate cancer urology lifestyle program with a specialist integrating urologist who can advise on specific dietary recommendations based on current evidence from the literature on the molecular nutrition.8. The team believe that a more holistic approach to treatment has real benefits in terms of clinical outcomes.
More research is needed to determine if and how eating habits can be changed to prevent populations from developing prostate cancer. For people diagnosed with prostate cancer, good nutrition and a balanced diet are important at every stage of the cancer journey.
1. Matsushita M, Fujita K, Nonomura N. Influence of diet and nutrition on prostate cancer. Int J Mol Sci 2020; 21: 1447.
2. Théderan I et al. Poor adherence to international cancer prevention recommendations in patients with prostate cancer: first results from the MARTINI-Lifestyle cohort. European Urology Focus 2020; 6: 935-940.
3. Paterson C, Roberts C, McKie A. Prostate cancer pre-adaptation and the importance of multimodal interventions for person-centered care and recovery. Semin Oncol Nurses 2020; 36.
4. Dunn J, Green A, Ralph N, Newton UK, Kneebone A, Frydenberg M, Chambers SK. Essential framework for prostate cancer survival: guidelines for practitioners. BJUI 2020.
5. Fleure L, Sara S. An exploration of the role of the prostate cancer nurse from two international perspectives. Semin Oncol Nurses 2020; 36 (4).
6. Ralph N, Chambers S, Pomery A, Oliffe J, Dunn J. Nurse-led supportive care intervention for men with advanced prostate cancer. NFB 2019; 46 (1): 92-103.
7. Paterson C, Robertson A, Smith A, Nabi G. Identifying the unmet supportive care needs of men living with and beyond prostate cancer: a systematic review. Eur J Oncol Nurses 2015; 19 (4): 405-18.
8. Dovey ZS, Tewari AK (2020) Creation of a prostate cancer lifestyle medicine program. In: Mechanick JI, Kushner RF (eds) Create an M lifestyle
About the Author
MBBCh, FC Urol (SA), MMed (Urol), Dip.Couns (AIPC)
Kalli is an internationally renowned urological surgeon specializing in oncology and robotic surgery. He trained and worked in South Africa, before moving to Australia where he worked at Macquarie University Hospital and Westmead Hospital. His passion for what he does extends beyond the operating room, through public health advocacy, education and community awareness of men’s health, cancer and cancer. sexuality.
Kalli has been involved with the Prostate Cancer Foundation of Australia for many years, advocating for improved cancer care and facilitating community prostate cancer support groups.