Eating More Meat Than Veggies? For Prostate Cancer, It Matters

It is now 8 years since the famous Ornish study was published, suggesting that 12 months on a strictly plant-based diet could reverse the progression of prostate cancer. For those unfamiliar with that landmark Ornish study, see  Cancer Reversal Through Diet?, which the Pritikin Foundation followed up on with Ex Vivo Cancer Proliferation Bioassay.

Wait a second. How were they able to get a group of older men to go vegan for a year? They home delivered prepared meals to their doors, I guess figuring men are so lazy they’ll just eat whatever is put in front of them.

But what about out in the real world? Realizing that you can’t even get most men with cancer to eat a measly five servings of fruits and veggies, researchers settled on just trying to change their A to V ratio—the ratio of animal to vegetable proteins—and indeed were successful in cutting this ratio by at least half, from about 2 to 1 animal to plant, to kind of half vegan, 1 to 1.

How’d they do? Their cancer appeared to slow down. The average PSA doubling time (an estimate of how fast the tumor may be doubling in size) in the “half vegan” group slowed from 21 months to 58 months. So the cancer kept growing, but with a part-time plant-based diet they were able to slow down the tumor’s expansion. What Ornish got, though, was an apparent reversal in cancer growth—the PSA didn’t just rise slower, it trended down, which could be an indication of tumor shrinkage. So the ideal A to V ratio may be closer to zero.

If there’s just no way grandpa’s going vegan, and we just have half-measures, which might be the worst A and the best V? Eggs and poultry may be the worst, respectively doubling and potentially quadrupling the risk of cancer progression in a study out of Harvard. Twice the risk eating less than a single egg a day and up to quadruple the risk eating less than a single serving of chicken or turkey.

And if you could only add one thing to your diet, what would it be? Cruciferous vegetables. Less than a single serving a day of either broccoli, Brussels sprouts, cabbage, cauliflower, or kale may cut the risk of cancer progression (defined as the cancer coming back, spreading to the bone, or death) by more than half.

The animal to plant ratio might be useful for cancer prevention as well. For example, in the largest study ever performed on diet and bladder cancer, just a 3% increase in the consumption of animal protein was associated with a 15% higher risk of bladder cancer, whereas a 2% increase in plant protein intake was associated with a 23% lower risk. Even little changes in our diets can have significant effects.

What else might help men with prostate cancer? See Flaxseed vs. Prostate Cancer and Saturated Fat & Cancer Progression. What about preventing it in the first place? See:

Poultry and eggs may be related to cancer risk in a variety of ways:

Crucifers may also help with other cancers. See:

Breast cancer is highlighted in my video Breast Cancer Survival Vegetable.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death and More Than an Apple a Day.

Poultry and Paralysis
Bladder Infections from Eating Chicken
Why Is Selling Salmonella-Tainted Chicken Still Legal?


Oleg Kobetz
Oleg Kobets3 years ago

Thank you

Michael A.
Michael A3 years ago


Deborah Sacco
.3 years ago

I guess everyone as their choice. It's almost 2 weeks I have not eaten any meat including chicken, and I am proud to call myself vegetarian. I don't miss it, when I go to the store I pass the meat section and it does nothing for me.

Jessica Grieshaber

Thanks for sharing

Keith H.
Keith H3 years ago


Karen Garnett
karen Garnett3 years ago

What I have found is that most folks just plain do not want to HEAR anything negative about the way they are nourishing their body. I have relatives that think I am a bit strange, just because I do pay attention to my nutrition. But they just don't seem to even want to hear anything negative about their own eating habits. And if a "convenience" food states that it has added vitamins, well--there ya go. It's all good, according to one of my family members. I try to add little nuggets of information when I can, but if there is resistance, there's isn't much I can do at this time. Sad!

Laurence Wuillemin
Past Member 3 years ago

Not ALL men are lazy ! what a broad-brush statement!
Who paid the study, that should be the first question to be asked. Then you know what they want to sell you... or in which direction they want you to act.

Michael A.
Michael A3 years ago


Lynn C.
Lynn C3 years ago


Sharon Richards
Sharon Richards3 years ago

Fruits and vegetables are the way to go. Meat and dairy products harm more than help. Vegans live on average 7 to 9 years longer than those eating meat and dairy. It's a win-win situation for people and animals. The people are healthier and the animals don't have to die.