Treating Advanced Prostate Cancer with Diet

Dr. Dean Ornish showed that a plant-based diet and lifestyle program could apparently reverse the progression of prostate cancer for early stage, localized, watch-and-wait cancer. What about for more advanced stage life-threatening disease?

Dr. Dean Ornish showed that a plant-based diet and lifestyle program could apparently reverse the progression of prostate cancer by making men’s bloodstreams nearly eight times better at suppressing cancer cell growth. But this was for early-stage, localized, watch-and-wait prostate cancer.

What about for more advanced-stage, life-threatening disease? There have been sporadic case reports in the literature suggesting benefit. For example, a man with extensive metastatic disease who had been given about three years to live went on a strict plant-based diet. Four years later, it appeared the cancer had disappeared. After six years, he got a little too comfortable, backslid a bit on the diet and began eating “turkey, tuna fish, and chicken,” then the cancer came raging back and he died. But that could have been a total coincidence. That’s the problem with case reports, which are kind of glorified anecdotes. You have no idea how representative the outcome is unless it’s studied formally. But, throughout the 20th century, all we had were these kinds of case reports for more advanced prostate cancer until 2001.

We had “preliminary evidence” based on all the case reports that “prostate cancer may be sensitive to diet even after metastasis develops. Plant-based diets may be associated with prolonged survival and instances of remission of bone metastasis in men with advanced disease.” So, researchers decided to put it to the test in a four-month intervention. They thought that too much saturated fat, too little fiber, and too much meat may be the biggest players in tumor promotion and progression, so they put people on a whole food plant-based diet of whole grains, beans, seeds, and fruits. Figuring this would be quite the departure from their regular diet, the researchers included a stress reduction component in hopes of improving dietary compliance.

Who were the subjects? The ten men in the study didn’t just have prostate cancer—they had all undergone a radical prostatectomy to remove their primary tumor and then subsequently had increasing PSA levels, indicative of probable metastatic disease. PSA stands for prostate-specific antigen. It’s only made by prostate cells, but the ten men had just had their entire prostates removed so their levels should have been zero. The fact that they not only still had some PSA, but that it was rising suggests that the surgery had failed, and the cancer had spread and was making a comeback.

At 2:43 in my video Treating Advanced Prostate Cancer with Diet: Part 1, you can view a graph showing the PSA levels for each of the men before the study began and see the speed at which their PSAs went up. If their PSA trajectories had stayed the same after four months of eating healthfully, it would mean the diet had had no effect. In that case, presumably, the cancer would have still been powering away and spreading just as fast as before. Instead, in two of the men, it looked as if the cancer had accelerated and grew even faster, but in the other eight men, the intervention appeared to work, apparently slowing down cancer growth. And, in three of the ten men, it didn’t just slow or stop, but appeared to reverse and shrink.

Why the different responses? Well, in the Ornish study, the more people complied with the diet and lifestyle recommendations, the better they did, as you can see at 3:31 in my video. Dietary changes only work if you actually do them. Just because you tell people to start eating a whole food plant-based diet, doesn’t mean patients actually do it. One can use fiber intake as a proxy for dietary compliance because all whole plant foods have fiber, and Ornish’s patients about doubled their fiber intake from 31 grams to 59 grams.

How did the ten men in the 2001 study do? They started out even worse, averaging 14 grams of fiber a day, and only made it up to 19 grams a day. That’s not a whole food plant-based diet—that doesn’t even meet the recommended minimum daily intake. As you can see at 4:18 in my video, only four of the ten men even increased their fiber intake at all, so that may explain the different responses. In fact, the man whose fiber improved the most had the best PSA result, and the man whose fiber intake dropped the most had the worst PSA result. Indeed, it appears the more changes they made to their diet, the better their results.

The researchers concluded that “a plant-based diet delivered in the context of MBSR [Mindfulness-Based Stress Reduction]…may slow the rate of tumor progression,” and, unlike other treatments, may give patients some control over their disease. And, as Ornish pointed out, “the only side effects are beneficial ones.”

Dr. Ornish and colleagues were able to show an apparent reversal in the progression of early-stage, localized prostate cancer with a plant-based diet and lifestyle program, and researchers at the University of Massachusetts and elsewhere showed a similar diet may help slow the progression of even advanced prostate cancer over a period of four months.

How about over six months? As I discuss in my video Treating Advanced Prostate Cancer with Diet: Part 2, researchers at University of California, San Diego put cancer patients through the same protocol as the four-month study. Once again, these were patients who had already been treated for invasive prostate cancer by either radical prostatectomy or radiation therapy, yet still had rising PSA levels, suggesting the treatment didn’t work and the cancer was on the move. “In those who have undergone a [cancer] recurrence, PSA typically tends to rise exponentially after prostatectomy or radiation therapy, reflecting the gradual, inexorable growth of the cancer in the body. After local treatment, the rate of PSA rise is the single best predictor of…development of overt metastatic disease, as well as of overall survival.” The next step would be hormonal therapy, which is chemical or surgical castration, but that has a list of side effects, including loss of libido, sexual function, strength, and vitality. “Therefore, many physicians employ a strategy of active surveillance” and try to hold off for as long as possible. If we’re just waiting, why not give diet a try?

Patients were “taught to increase intake of whole grains, vegetables, fruit, and legumes and to decrease meat, dairy, and refined carbohydrates.” Of all possible lifestyle interventions, why a whole food plant-based diet? If you look around the world, there are huge differences in prostate cancer rates, as you can see at 1:42 in my video, and our We’re #1! USA! USA! rates are up to a hundred times higher than some places in Asia, for example—and it’s not just genetic. Within one generation of migrating to the United States, cancer rates shoot up, and the grandkids of the immigrants end up with the same top-of-the-pile “approximate US rates.” A whole range of lifestyle factors have been looked at, but diet appears to have the greatest influence.

Specifically, “consumption of meat and dairy appears to increase risk, and consumption of plant-based foods appears to decrease risk.” Hence, the plant-based diet. A possible mechanism found in both meat and dairy products is arachidonic acid, an inflammatory compound that we make from omega-6-rich oils, like corn, sunflower, safflower, and cottonseed oils. It also comes “preformed” in animal-based foods and, in the American diet, is found particularly in chicken and eggs. In a petri dish, arachidonic acid appears to stimulate prostate cancer cell growth as much 200 percent, as you can see at 2:43 in my video.

So what happened when those researchers at University of California, San Diego asked men to remove processed and animal foods from their diet for six months? At 2:57 in my video, you can see a graph showing how fast the cancer patients’ PSA levels had been rising before starting the study. “In the absence of treatment, absolute levels of PSA tend to increase exponentially,” but upon eating more healthfully, nine of the ten study subjects showed an apparent slowing of cancer growth and four of the nine showed an apparent reversal in cancer growth. The average doubling time, an estimate of how long it would take for their cancer to double in size, slowed from doubling every year to closer to every ten years.

Other studies have used various diets and nutritional interventions, like vitamin supplements, but none has worked as well as this one—and the subjects’ compliance wasn’t even all that great. As you can see at 3:41 in my video, they did well in boosting their whole grain consumption in the first three months, but then backslid a bit, and they ate more vegetables, including a serving of greens, and an extra serving of fruit, at least early on. And, in the beginning, they at least ate one whole serving of legumes a day. So the researchers “did observe some [dietary] recidivism by 6 months,” with subjects sliding back into old habits. Given that, they checked to see if the study participants were better able to beat off the disease during that earlier period. And, indeed, at the end of the first three months, on average, there was PSA reversal. “Changes in the rate of rise in PSA, an indicator of disease progression, were in the opposite direction as changes in the intake of plant-based food groups, raising the provocative possibility that PSA may have inversely tracked intake of these foods and suggesting that adoption of a plant-based diet may have therapeutic potential in the management of this condition.”

Their findings suggest that, without further surgery, radiation, or chemotherapy, disease progression can be slowed or even reversed, despite “the prevailing scientific consensus…that cancer progression is largely irreversible.” The researchers state their “findings do not refute the benefits of standard therapies or guarantee that a plant-based diet and stress reduction will always induce remission,” but their results “do contribute to a growing [medical] literature that suggests that in at least some circumstances, cancer may be partly reversible and that modification of dietary and lifestyle factors may be able to help prevent disease spread”—all without getting their testicles cut off.

Hold on. We can make men’s bloodstreams nearly eight times better at suppressing cancer cell growth? See How Not to Die from Cancer.

It’s not all or nothing, though. Any movement we make towards healthy eating may help. See Prostate Cancer Survival: The A/V Ratio .


You may also be interested in:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Saffron for Erectile Dysfunction

What are the effects of both oral and topical application of the spice saffron for impotence in men?

“Saffron has traditionally been considered an aphrodisiac.” The spice has been shown to improve Prozac-induced sexual dysfunction in women and men, significantly improving erectile function. If it works for drug-induced dysfunction, might it also work for just regular erectile dysfunction? This is the topic of my video Saffron for Erectile Dysfunction.

Why not just use pills like Viagra? They can work, but many men stop using them for “various reasons such as adverse side-effects.” In fact, nearly half of men decide the cons outweigh the pros. For men who don’t like drugs, there’s always surgery—the implantation of penile prosthetics. Unbelievably, penile implant usage evidently dates back to the 16th century. Early experiments involved transplanting patients’ rib cartilage or even their actual rib into their penis. Thankfully, space-age technologies in the 1960s allowed men to keep their ribcages intact. Originally, the implants left men in a “permanently erect state,” but then the “Flexirod” was invented with a hinge in the middle so the device could be bent down in half “for improved concealment.” Of course, proper sizing is important: If the implants are too small, there can be drooping at the tip, leading to a “supersonic transport (SST) deformity.” Why supersonic? “Because of its resemblance to the nose of the Concorde [jet]. Overlong prostheses can also be a problem, and with the semi-rigid rods erosion [out of the penis] can occur.” “Although a penile prothesis generally perforates into the urethra, it can also extrude through the glans [tip] or corporeal shaft.” Ouch.

Now, there are inflatable devices, as you can see at 2:06 in my video, and, perhaps one day, there will be “expandable foams that respond to external magnetic fields” or metal-mesh technology “that could expand and retract in a cage-like fashion.” (Can you imagine trying to get through airport security with that?)

There’s got to be a better way.

In one study, twenty men with erectile dysfunction took 200 mg (about a quarter teaspoon) of saffron a day and were followed for ten days. But first, they were brought into the “RigiScan room,” where they were hooked up to a “computer-controlled, battery-powered system for recording of penile tumescence”—meaning swelling—“and rigidity.” They were then “monitored while watching a visual sexual stimulation (VSS) video tape,” though use of the device is controversial, described as an “expensive, complicated, and time-consuming effort.” But, as you can see at 3:00 in my video, after the ten days of taking saffron, there did appear to be a significant improvement in tip and base rigidity and tumescence. “Whether it is possible to replace [Viagra-type drugs] with this golden plant requires further research with a bigger sample size.” But it’s not just size that matters. The researchers didn’t use a control, so all of this could have just been one big placebo effect.

Finally, though, researchers pitted saffron against Viagra in a head-to-head challenge. Normally there’s a third group—a placebo group—as well, but evidently, they felt it would be unethical to let men go 12 weeks without an effective treatment. The saffron appeared safer than the drug, with significantly fewer side effects like severe headaches, hot flushes, nasal congestion, and nausea, but…it was not effective at all. That’s why I never produced a video on the subject—it just doesn’t seem to help erectile dysfunction. Could it be, though, that they made the mistake of taking the saffron orally, as opposed to rubbing it on their penis? About half of middle-aged men in the United States appear to suffer from erectile dysfunction, so how about a randomized, double-blind, placebo-controlled study. Researchers studied the effects of a gel containing either 1 percent saffron or a “golden yellow food color” so the two gels looked the same. “Both groups were trained to rub a pea-sized amount of the gel on their penis half an hour before a sexual intercourse. One month later, all patients were reassessed using the same questionnaire.” As you can see at 4:40 in my video, compared to the food-coloring gel, the saffron gel led to significant improvements in erectile function, sexual desire, and overall satisfaction. The effects are attributed to a compound in saffron that enhances nitric oxide production in the arteries. But, if that’s the case, then it’s probably better to treat the cause and prevent the vascular dysfunction in the first place by eating a diet packed with nitrate-rich vegetables.

Those who want to clean out all their arteries and treat the cause may want to check out my video Survival of the Firmest: Erectile Dysfunction and Death.


Another video worth watching is Best Food for Antidepressant-Induced Sexual Dysfunction. I have a few others on the golden spice:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

70% Taking Common Antidepressants Suffer Sexual Side Effects

What’s the latest on treating depression with the spice saffron? Years ago, I covered a head-to-head comparison of saffron versus Prozac for the treatment of depression in my video Saffron vs. Prozac, and saffron seemed to work just as well as the drug. In the years since, five other studies have found that saffron beat out placebo or rivaled antidepressant medications.

It may be the spice’s red pigment, crocin, since that alone beat out placebo as an adjunct treatment, significantly decreasing symptoms of depression, symptoms of anxiety, and general psychological distress. Perhaps, its antioxidants played a role in “preventing free radical-induced damage in the brain.” The amount of crocin the researchers used was equivalent to about a half teaspoon of saffron a day.

If the spice works as well as the drugs, one could argue that the spice wins, since it doesn’t cause sexual dysfunction in the majority of men and women like most prescribed antidepressants do. SSRI drugs like Prozac, Paxil, and Zoloft cause “adverse sexual side effects” in around 70 percent of people taking them. What’s more, physicians not only significantly underestimate the occurrence of side effects, but they also tend to underrate how much they impact the lives of their patients.

Not only is this not a problem with saffron, the spice may even be able to treat it, as I explore in my video Best Food for Antidepressant-Induced Sexual Dysfunction. “In folk medicine, there is a widely held belief that saffron might have aphrodisiac effects.” To test this, men with Prozac-induced sexual impairment were randomized to saffron or placebo for a month. By week four, the saffron group “resulted in significantly greater improvement in erectile function…and intercourse satisfaction,” and more than half of the men in the saffron group regained “normal erectile function.” The researchers concluded that saffron is an “efficacious treatment” for Prozac-related erectile dysfunction. It has all been found to be effective for female sexual dysfunction, as well, as you can see at 2:35 in my video. Female sexual function increased by week four, improving some of the Prozac-induced sexual problems but not others. So, it may be better to try saffron in the first place for the depression and avoid developing these sexual dysfunction problems, since they sometimes can persist even after stopping the drugs, potentially worsening one’s long-term depression prognosis.

This includes unusual side effects, such as genital anesthesia, where you literally lose sensation. It can happen in men and women. More rarely, antidepressants can induce a condition called restless genital syndrome. You’ve heard of restless legs syndrome? Well, this is a restless between-the-legs syndrome. These PSSDs, or Post-SSRI Sexual Dysfunctions, meaning dysfunctions that appear or persist after stopping taking these antidepressants, can be so serious that “prescribing physicians should mention the potential danger of the occurrence of genital (e.g., penile or vaginal) anesthesia to every patient prior to any SSRI treatment.” If you’re on one of these drugs, did your doctor warn you about that?

All hope is not lost, though. Evidently, penile anesthesia responds to low-power laser irradiation. After 20 laser treatments to his penis, one man, who had lost his penile sensation thanks to the drug Paxil, partially regained his “penile touch and temperature sensation.” However, he still couldn’t perform to his girlfriend’s satisfaction, and she evidently ended up leaving him over it, which certainly didn’t help his mood. But, before you feel too badly for him, compare a little penile light therapy to clitoridectomy, clitoris removal surgery, or another Paxil-related case where a woman’s symptoms only improved after six courses of electroshock therapy.

Pass the paella!


For more on the spice, check out:

Those drug side effects sound devastating, but depression is no walk in the park. However, when one balances risk and benefit, one assumes that there are actually benefits to taking them. That’s why the shocking science I explored in Do Antidepressant Drugs Really Work? is so important.

What else may boost mood? A healthy diet and exercise:

For more on sexual health generally, see:

What else can spices do? Here’s just a taste:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: