Choline and prostate cancer
DNC News: www.DenverNaturopathic.com
Jacob Schor, ND, FABNO
February 24, 2013
A study by Erin Richman, now of the University of San Francisco, which was published in October 2012, had added another dimension to our understanding of prostate cancer. While it’s tempting to respond to patients who want to know what sort of diet they should follow to prevent cancer recurrence, most of the time we are limited to general answers. More and more it is starting to seem that the suggested diet should vary by type of cancer. Erin Richman’s work over the last several years provides us with a greater understanding of several of the key chemicals that may incite prostate cancer to grow.
Why this study was conducted will seem obvious if we first go back and review an earlier study Richman conducted and that was published three years ago, in March 2010. That earlier study, which was published in the American Journal of Clinical Nutrition, had examined the effect meat, fish, poultry and egg consumption had on the risk of prostate cancer progression. She surprised many of us by reporting that egg and poultry consumption significantly increased risk of cancer progression while meat did not have a significant impact. Less than half a dozen eggs consumed per week was associated with a doubling in risk of progression. Eating chicken with skin on it also had a similar doubling effect. At the time Richman theorized that it might be the high choline content of the eggs that was responsible and also the high levels of heterocyclic amines produced in the chicken skin during cooking.
In this study intake of dietary choline, supplements containing choline, and betaine (a choline metabolite) were examined prospectively and compared with the risk of lethal prostate cancer.
Data from the 47,896 men in the Health Professionals Follow-Up Study were analyzed. The diets of the 4,282 men who were diagnosed with non-metastatic disease during the follow-up period were assessed with a validated questionnaire 6 times during 22 years of follow-up period. The primary outcome measure was lethal prostate cancer. A total of 695 deaths from prostate cancer occurred during the 879,627 person-years of data collected.
Men in the highest quintile of choline intake had a 70% increased risk of dying from prostate cancer (HR: 1.70; 95% CI: 1.18, 2.45; P-trend = 0.005) than men in the lowest quintile.
In this current study, the top 5 foods contributing to choline in the diets of the participants were whole eggs, beef, skim milk, reduced-fat milk, and poultry without skin. Consumption of these particular foods is already associated with prostate cancer risk. [1,2,3]
Typically we have thought that the link between meat and prostate cancer results from the carcinogens (in particular the heterocyclic amines) formed during cooking. While Figg reported in October 2012 that men who consume the most ground beef have more than double their risk of aggressive prostate cancer, risk varied by cooking: “Interestingly, the consumption of rare or less cooked meat was not associated with an increased risk of prostate cancer.” This suggests it isn’t just the choline content but also the heterocyclic amine production during cooking.
This new study of Richman’s is the first time that the potential of milk and beef to increase prostate cancer risk has been attributed to their choline content alone.
While the link between choline and fatal prostate cancer is becoming clear, the risk benefit analysis remains murky. Choline is an essential nutrient and is associated with a number of positive health impacts, possibly useful at prevention of fatty liver disease and in particular, cognitive decline in the elderly. People should probably not start on choline free diets.
This current paper, in light of Richman’s earlier study, solidly reinforces the theory that high dietary choline promotes prostate cancer. For men with prostate cancer this concern probably outweighs worry about Alzheimer’s disease.
We should be aware that there are other dietary factors associated with prostate cancer besides high choline and heterocyclic amines. A study by Stott-Miller et al published in January 2013 reported significant associations between fried food consumption and prostate cancer. Eating French fries once a week or more increased risk of prostate cancer by 37%. Fried chicken once a week increased risk by 30%, doughnuts by 35% and fried fish by 32%. Risk of developing aggressive prostate cancer increased slightly more, for example eating fried fish increased risk of aggressive disease by 41%. While these associations do not speak to risk of progression or fatality, they do further define the dietary advice we should provide to prostate cancer patients.
Patients rarely want to know all these details; instead they want a clear bottom line. We have to explain that this knowledge is still a work in progress.
Reference: Richman EL, Kenfield SA, Stampfer MJ, Giovannucci EL, Zeisel SH, Willett WC, Chan JM. Choline intake and risk of lethal prostate cancer: incidence and survival. Am J Clin Nutr. 2012 Oct;96(4):855-63.
A link to an article about Richman’s earlier study:
Song Y, Chavarro JE, Cao Y, Qiu W, Mucci L, Sesso HD, Stampfer MJ, et al. Whole Milk Intake Is Associated with Prostate Cancer-Specific Mortality among U.S. Male Physicians. J Nutr. 2013 Feb;143(2):189-96.
1. Figg WD 2nd. How do you want your steak prepared? The impact of meat consumption and preparation on prostate cancer. Cancer Biol Ther. 2012 Oct;13(12):1141-2
2. Joshi AD, Corral R, Catsburg C, Lewinger JP, Koo J, John EM, Ingles SA, Stern MC. Red meat and poultry, cooking practices, genetic susceptibility and risk of prostate cancer: results from a multiethnic case-control study. Carcinogenesis. 2012 Nov;33(11):2108-18.
3. Figg WD 2nd 2012
4. Stott-Miller M, Neuhouser ML, Stanford JL. Consumption of deep-fried foods and risk of prostate cancer. Prostate. 2013 Jan 17.
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