Written by Luc Geeraert and the CAM-Cancer Consortium.
Updated January 20, 2017

Ornish diet and lifestyle modification programme

What is it?


Dean Ornish, M.D., is founder and president of the non-profit Preventive Medicine Research Institute in Sausalito, California, and clinical professor of medicine at the University of California, San Francisco 1. In his popular book entitled “The Spectrum”, Ornish provides examples of various individually tailored diet and lifestyle programmes, including one to prevent/reverse certain types of prostate and breast cancer 2.


The Ornish diet and lifestyle modification programme combines a supplemented vegan diet with exercise, stress management, smoking cessation, and group support sessions 3.

The vegan diet itself is very low in fat (<10%) and in simple carbohydrates, but high in fibre, and includes predominantly fruits, vegetables, whole grains, and legumes, all in their natural unrefined forms 3. Meat, plant foods high in fat (e.g., nuts, seeds, and avocados), fat dairy products, and refined carbohydrates are banned. Consumption of minimal amounts of non-fat dairy products such as skimmed milk, non-fat yoghurt, and non-fat cheese is allowed. This diet is supplemented with soy (one serving of tofu plus 58 g of a fortified soy protein powdered beverage per day), fish oil (3 g per day), vitamin E (400 IU per day), selenium (200 µg per day), and vitamin C (2 g per day). Alcohol is allowed in small amounts but not encouraged. The diet is in general concordance with the American Cancer Society guidelines 4.

The exercise part consists of moderate aerobic exercise (30 min of walking, 6 days per week) 3.

Stress management includes yoga-based stretching, breathing, meditation, imagery, and progressive relaxation (1 hour per day) 3.

Group support sessions (1 hour per week) are included to support adherence to lifestyle changes 3.


The earlier work of Ornish and colleagues in the 1980s and 1990s demonstrated that diet, lifestyle changes, and smoking cessation could not only halt the progression of ischemic heart disease, but could actually reverse it 5-7. Given that cardiovascular disease is the primary or secondary cause of death in men with prostate cancer, and that a large number of epidemiological and laboratory studies suggested that diet and lifestyle may play an important role in the development of prostate cancer, the Ornish group began exploring the possible effects of such an intervention in the late 1990s 3,8.

Claims of efficacy

Ornish and colleagues 3,8-10, suggest the possibility that some or all aspects of the combined lifestyle changes (diet + exercise + stress management) enable patients with early-stage prostate cancer to delay or avoid conventional treatment and/or improve quality of life.

Mechanism(s) of action

The mechanism of action of the Ornish diet and lifestyle modification programme was examined in only one prospective pilot study that enrolled 31 low-risk prostate cancer patients 11-12.

Differences in RNA samples from needle biopsies taken from normal prostate tissue before intervention compared to RNA samples taken after 3 months of intervention indicated that application of the Ornish diet and lifestyle modification programme may modulate gene expression in the prostate 11. Pathway analysis identified significant modulation of biological processes playing critical roles in tumorigenesis, including protein metabolism and modification, intracellular protein traffic, and protein phosphorylation.

In peripheral blood mononuclear cells (PBMCs) of the patients, telomerase activity and hence telomere maintenance capacity was significantly increased 12,21. Telomeres are protective DNA-protein complexes that promote chromosomal stability, and shortness of telomeres is a prognostic marker of ageing, disease, and premature morbidity.

Alleged indication(s)

The programme is indicated for early-stage prostate cancer patients (biopsy-documented; Gleason score less than 7; serum prostate-specific antigen (PSA) levels of 4-10 ng/ml; Stages T1 and T2) before surgical intervention or hormone-deprivation, i.e. patients on active surveillance (watchful waiting) closely monitoring disease progress 11,13-14.

Prevalence of use


Legal issues


Costs and expenditure

The diet itself is inexpensive as it only concerns common food sources and a few inexpensive supplements. The counselling and group sessions connected to the programme result in a cost of around $7,000 per year 15.


Luc Geeraert, CAM-Cancer Consortium. Ornish diet and lifestyle modification programme [online document]. http://cam-cancer.org/The-Summaries/Dietary-approaches/Ornish-diet-and-lifestyle-modification-programme. January 20, 2017.

Document history

Most recent update and revision in January 2017 by Luc Geeraert.

Summary assessed as up to date in September 2013 by Barbara Wider.
Update and revision in November 2012 by Luc Geeraert.
Summary first published in September 2011, authored by Luc Geeraert. 


  1. Deanornish.com [Internet]. Dean Ornish, MD, Bio. 2011. [cited 19th December 2016]. Available from: http://deanornish.com/about/.
  2. Ornish D. The Spectrum: A Scientifically Proven Program to Feel Better, Live Longer, Lose Weight, and Gain Health. New York: Ballantine Books, 2007.
  3. Ornish D, Weidner G, Fair WR, Marlin R, Pettengill EB, Raisin CJ, Dunn-Emke S, Crutchfield L, Jacobs FN, Barnard RJ, Aronson WJ, McCormac P, McKnight DJ, Fein JD, Dnistrian AM, Weinstein J, Ngo TH, Mendell NR, Carroll PR. Intensive lifestyle changes may affect the progression of prostate cancer. J. Urol. 2005 September;174(3):1065-1069.
  4. Rock CL, Doyle C, Demark-Wahnefried W, Meyerhardt J, Courneya KS, Schwartz AL, Bandera EV, Hamilton KK, Grant B, McCullough M, Byers T, Gansler T. Nutrition and physical activity guidelines for cancer survivors. CA Cancer J Clin. 2012 Jul-Aug;62(4):243-74. doi: 10.3322/caac.21142.
  5. Ornish D. Can life-style changes reverse coronary atherosclerosis? Hosp. Pract. (Off. Ed.). 1991 May 15;26(5):123-126, 129-132.
  6. Ornish D, Scherwitz LW, Doody RS, Kesten D, McLanahan SM, Brown SE, DePuey E, Sonnemaker R, Haynes C, Lester J, McAllister GK, Hall RJ, Burdine JA, Gotto AM Jr. Effects of stress management training and dietary changes in treating ischemic heart disease. JAMA. 1983 January 7;249(1):54-59.
  7. Ornish D, Scherwitz LW, Billings JH, Brown SE, Gould KL, Merritt TA, Sparler S, Armstrong WT, Ports TA, Kirkeeide RL, Hogeboom C, Brand RJ. Intensive lifestyle changes for reversal of coronary heart disease. JAMA. 1998 December 16;280(23):2001-2007.
  8. Ornish DM, Lee KL, Fair WR, Pettengill EB, Carroll PR. Dietary trial in prostate cancer: Early experience and implications for clinical trial design. Urology. 2001 April;57(4 Suppl 1):200-201.
  9. Daubenmier JJ, Weidner G, Marlin R, Crutchfield L, Dunn-Emke S, Chi C, Gao B, Carroll P, Ornish D. Lifestyle and health-related quality of life of men with prostate cancer managed with active surveillance. Urology. 2006 January;67(1):125-130.
  10. Frattaroli J, Weidner G, Dnistrian AM, Kemp C, Daubenmier JJ, Marlin RO, Crutchfield L, Yglecias L, Carroll PR, Ornish D. Clinical events in prostate cancer lifestyle trial: results from two years of follow-up. Urology. 2008 December;72(6):1319-1323.
  11. Ornish D, Magbanua MJ, Weidner G, Weinberg V, Kemp C, Green C, Mattie MD, Marlin R, Simko J, Shinohara K, Haqq CM, Carroll PR. Changes in prostate gene expression in men undergoing an intensive nutrition and lifestyle intervention. Proc. Natl. Acad. Sci. USA. 2008 Jun 17;105(24):8369-8374.
  12. Ornish D, Lin J, Daubenmier J, Weidner G, Epel E, Kemp C, Magbanua MJ, Marlin R, Yglecias L, Carroll PR, Blackburn EH. Increased telomerase activity and comprehensive lifestyle changes: a pilot study. Lancet Oncol. 2008 November;9(11):1048-1057.
  13. Cooperberg MR, Broering JM, Kantoff PW, Carroll PR. Contemporary trends in low risk prostate cancer: risk assessment and treatment. J. Urol. 2007 September;178(3 Pt 2):S14-S19.
  14. Klotz L. Low-risk prostate cancer can and should often be managed with active surveillance and selective delayed intervention. Nat. Clin. Pract. Urol. 2008 January;5(1):2-3.
  15. Zeng W, Stason WB, Fournier S, Razavi M, Ritter G, Strickler GK, Bhalotra SM, Shepard DS. Benefits and costs of intensive lifestyle modification programs for symptomatic coronary disease in Medicare beneficiaries. Am Heart J. 2013 May;165(5):785-92. doi: 10.1016/j.ahj.2013.01.018.
  16. Kronenwetter C, Weidner G, Pettengill E, Marlin R, Crutchfield L, McCormac P, Raisin CJ, Ornish D. A qualitative analysis of interviews of men with early stage prostate cancer: the Prostate Cancer Lifestyle Trial. Cancer Nurs. 2005 Mar-April;28(2):99-107.
  17. Dunn-Emke SR, Weidner G, Pettengill EB, Marlin RO, Chi C, Ornish DM. Nutrient adequacy of a very low-fat vegan diet. J. Am. Diet Assoc. 2005 September;105(9):1442-1446.
  18. Dewell A, Weidner G, Sumner MD, Chi CS, Ornish D. A very-low-fat vegan diet increases intake of protective dietary factors and decreases intake of pathogenic dietary factors. J. Am. Diet Assoc. 2008 February;108(2):347-356.
  19. Dewell A, Weidner G, Sumner MD, Barnard RJ, Marlin RO, Daubenmier JJ, Chi C, Carroll PR, Ornish D. Relationship of dietary protein and soy isoflavones to serum IGF-1 and IGF binding proteins in the Prostate Cancer Lifestyle Trial. Nutr. Cancer. 2007;58(1):35-42.
  20. Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes: Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000.
  21. Ornish D, Lin J, Chan JM, Epel E, Kemp C, Weidner G, Marlin R, Frenda SJ, Magbanua MJ, Daubenmier J, Estay I, Hills NK, Chainani-Wu N, Carroll PR, Blackburn EH. Effect of comprehensive lifestyle changes on telomerase activity and telomere length in men with biopsy-proven low-risk prostate cancer: 5-year follow-up of a descriptive pilot study. Lancet Oncol. 2013 Oct;14(11):1112-20. doi: 10.1016/S1470-2045(13)70366-8.