Food Combining for Prostate Cancer

What would happen if you secretly gave cancer patients four of the healthiest foods?

In my video Pomegranate vs. Placebo for Prostate Cancer, I discussed how pomegranate pills appeared useless in the treatment for prostate cancer, and the same disappointing results were seen with a pomegranate beverage, but that was just a pomegranate extract as well. So, maybe the pomegranate itself “cannot be blamed for the ineffectiveness seen in the study” but rather the low dose of the pomegranate active principles in the extract. But what is the active principle? Extracts will boast about the level of ellagic acid, definitely “one of the most potent of the phytochemicals found in pomegranate. However, it is not as strong as pomegranate” itself.

What researchers mean is that the components may act synergistically: The whole may be greater than the sum of its parts. As you can see at 1:07 in my video Best Supplements for Prostate Cancer, human prostate cancer cells in a petri dish churned away at 100 percent growth, but after dripping on a pomegranate fraction, the cancer growth rate was cut by 30 percent. However, dripping on a different fraction appeared useless. What do you think would happen if you added them both together? 30% suppression + 0% suppression = 70% suppression! That’s synergy, where 1 + 1 is greater than 2. Under a microscope, prostate cancer cells appeared sparser with the combination of fractions. “Any attempt to characterize the phytoceutical power of a medicinal food by standardizing a single chemical is missing the entire point” of plant-based medicine. So, the standardized extracts represent a “cynical, lucre-driven [money-driven] attempt to replace the power of the pomegranate with the power of ellagic acid. The pomegranate needs no such tricks or enhancements.” It’s powerful as is. So, why don’t researchers just try the fruit on cancer patients?

Because you can’t stuff a pomegranate in a pill, so you can’t compare it to an indistinguishable sugar pill placebo. Drugs are easy to study. People don’t know if they are taking the active drug or a placebo, but they tend to notice if they’re eating a pomegranate or not. So, if you gave a bunch of cancer patients some pomegranates to eat and the cancer slowed down, you wouldn’t know if it was the pomegranates or just the placebo effect. Of course, the patients wouldn’t care. They’d just care that they got better. But, to change medical practice, we want to know if the fruit is actually something special. I suppose you could create some kind of pomegranate smoothie versus a fake smoothie, but that sounds logistically difficult. So, researchers tried powdering it. Three times a day, 199 men with prostate cancer got either a placebo or a tablet containing 100 mg of powdered whole pomegranate—the whole fruit with just the water taken out. How much can fit in a tablet? It comes out to be about six pomegranate seeds’ worth a day, about 1/100th of a pomegranate each day. Since so little could fit into a pill, researchers tried to maximize their chances of beating back the cancer using diversity.

As you can see at 4:01 in my video, two groups of people ate approximately the same amount of fruits and vegetables, but one group ate a relatively low biological diversity diet, where they ate tons of really healthy foods but just less variety than did a second group who ate smaller servings of a high diversity diet. Which group do you think would win in terms of protecting their DNA from free radical damage? The high diversity group. This suggests that “smaller amounts of many phytochemicals may have greater potential to exert beneficial effects than larger amounts of fewer phytochemicals.”

Same result for inflammation. Greater variety in fruit and vegetable intake is associated with lower inflammation even if you eat the same number of servings. Same with improving cognitive function, too. Greater variety in fruit and vegetable intake is also associated with a better mental status, executive function, attention, and memory function in some cases, even after adjustment for total quantity. So, if you have two people eating the same number of servings of healthy foods, the one eating a greater variety may do better.

Going back to the study with the 199 prostate cancer patients getting either a placebo or a tablet with 100 mg of powdered whole pomegranate three times daily, the researchers didn’t just put in pomegranate powder. They also added powdered broccoli, powdered turmeric, and powdered green tea concentrate. So, the tablet contained a fruit, a vegetable, a spice, and a leaf in tiny amounts—about one floret of broccoli a day, less than an eighth of a daily teaspoon of turmeric, and about one sixth of a tea bag worth of green tea. All great plants, but could such tiny amounts actually affect the progression of cancer? Yes. As you can see at 5:55 in my video, in the group of men with early stage prostate cancer trying to avoid surgery, the PSA levels in the placebo group rose nearly 50 percent, indicating that the cancer continued to flourish, whereas the PSAs didn’t rise at all in the pomegranate, broccoli, turmeric, and green tea food supplement group. And, in those with more advanced disease—patients who had already had surgery or radiation and were trying to avoid chemo—there was a 70 percent greater rise in PSA levels in the placebo group. This was enough to significantly delay some of these more toxic treatments. Indeed, the study found significant, short-term, favorable effects. However, they only had enough money to run the study for six months, because it was a “non-commercial” endeavor, funded by charities, not some supplement company. In fact, there was no supplement until the investigators dreamed it up from scratch for the study. Of course, now there’s a supplement, given the study’s extraordinary results, but the only reason the researchers put the foods in pill form was to match it with a placebo. In my mind, what this study should tell cancer patients is to eat curried broccoli with fruit for dessert and to sip some green tea. A completely plant-based diet may even shrink the tumor, not just slow it down, but there’s no reason we can’t do both with a plant-based diet chock full of especially powerful plants.

I love that study! You and I both know why these types of studies aren’t performed more often. Who would profit? (Other than the millions of people suffering and dying from cancer, of course!)

The note I ended on, the landmark Ornish study, is detailed in Cancer Reversal Through Diet. For those unwilling or unable to make such significant dietary changes, there’s still something you can do. See Prostate Cancer Survival: The A/V Ratio. Changing a Man’s Diet After a Prostate Cancer Diagnosis isn’t easy!


For more on the 2 + 2 > 4 concept, see Food Synergy.

What about preventing prostate cancer in the first place? Check out my videos like Prostate Cancer and Organic Milk vs. Almond Milk and Eggs, Choline, and Cancer to get a sense of what you might want to avoid. But, in terms of what to eat, see The Role of Soy Foods in Prostate Cancer Prevention and Fermented or Unfermented Soy Foods for Prostate Cancer Prevention?.

Also, see: 

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:

Using Green Tea to Help Prevent Cancer and Treat Cancer

Tea consumption is associated with a reduced risk of heart disease, stroke, and premature death in general, with each additional cup of green tea a day associated with a 4-percent lower mortality risk. So, perhaps “drinking several cups of tea daily can keep the doctor away,” as well as the mortician—but what about cancer?

As I discuss in my video Can Green Tea Help Prevent Cancer, there is “growing evidence from laboratory, epidemiologic [population], and human intervention studies that tea can exert beneficial disease-preventive effects” and, further, may actually “slow cancer progression.” Let’s review some of that evidence.

Not only do those who drink a lot of tea appear to live longer than those who drink less, as you can see at 0:49 in my video, drinking lots of tea may also delay the onset of cancer. At 0:56 in my video, you can see a table titled “Average age at cancer onset and daily green tea consumption.” The green tea intake is measured in Japanese tea cups, which only contain a half a cup, so the highest category in the table is actually greater than or equal to five full cups of tea, not ten as it appears in the table. Women who did get cancer appeared to get it seven years later if they had been drinking lots of tea compared to those who had consumed less. Men, however, had a three-year delay in cancer onset if they had consumed more than five full cups of green tea daily, the difference potentially “due to higher tobacco consumption by males.”

Green tea may be able to interfere with each of the stages of cancer formation: the initiation of the first cancer cell, promotion into a tumor, and then subsequent progression and spread, as you can see at 1:24 in my video. Cancer is often initiated when a free radical oxidizes our DNA, causing a mutation, but, as you can see at 1:44 in my video, we can get a nice “spike of antioxidant power” of our bloodstream within 40 minutes of drinking green tea. “This increase may, in turn, lower oxidative damage to DNA and so decrease risk of cancer.”

Furthermore, in terms of genoprotective effects—that is, protecting our genes—pre-existing oxidation-induced DNA damage was lower after drinking green tea, suggesting consumption can boost DNA repair as well. We didn’t know for certain, however…until now.

There is a DNA-repair enzyme in our body called OGG1. As you can see at 2:15 in my video, within one hour of drinking a single cup of green tea, we can boost OGG1’s activity, and after a week of tea drinking, we can boost it even higher. So, “regular intake of green tea has additional benefits in the prevention and/or repair of DNA damage.” In fact, tea is so DNA-protective it can be used for sperm storage for fresh samples until they can be properly refrigerated.

What’s more, tea is so anti-inflammatory it can be used for pain control as a mouthwash after wisdom tooth surgery, as you can see at 2:41 in my video. In terms of controlling cancer growth, at a dose of green tea compounds that would make it into our organs after drinking six cups of tea, it can cause cancer cells to commit suicide—apoptosis (programmed cell death)—while leaving normal cells alone. There are a number of chemotherapy agents that can kill cancer through brute force, but that can make normal cells vulnerable, too. So, “[g]reen tea appears to be potentially an ideal agent for [cancer] prevention”: little or no adverse side-effects, efficacious for multiple cancers at achievable dose levels, and able to be taken orally. We have a sense of how it works—how it stops cancer cells from growing and causing them to kill off themselves—and it’s cheap and has a history of safe, acceptable use. But, all of this was based on in-vitro studies in a test tube. “It needs to be evaluated in human trials,” concluded the researchers. Indeed, what happens when we give green tea to people with cancer? Does it help?

Tea consumption may reduce the risk of getting oral cancer. Not only may the consumption of tea boost the antioxidant power of our bloodstream within minutes and decrease the amount of free-radical DNA damage throughout our systems over time, but it can also increase the antioxidant power of our saliva and decrease the DNA damage within the inner cheek cells of smokers, though not as much as stopping smoking all together. You can see several graphs and tables showing these findings in the first 35 seconds of my video Can Green Tea Help Treat Cancer?.

Might this help precancerous oral lesions from turning into cancerous oral lesions? More than 100,000 people develop oral cancer annually worldwide, with a five-year overall survival rate of less than the flip of a coin. Oral cancer frequently arises from precancerous lesions in the mouth, each having a few percent chance of turning cancerous every year. Can green tea help?

Fifty-nine patients with precancerous oral lesions were randomized into either a tea group, in which capsules of powdered tea extract were given and their lesions were painted with green tea powder, or a control group, who essentially got sugar pills and their lesions painted with nothing but glycerin. As you can see at 1:23 in my video, within six months, lesions in 11 out of the 29 in the tea group shrunk, compared to only 3 of 30 in the placebo group. “The results indicate that tea treatment can improve the clinical manifestations of the oral lesions.”

The most important question, though, is whether the tea treatment prevented the lesions from turning cancerous. Because the trial only lasted a few months, the researchers couldn’t tell. When they scraped some cells off of the lesions, however, there was a significant drop in DNA-damaged cells within three months in the treatment groups, suggesting that things were going in the right direction, as you can see at 1:46 in my video. Ideally, we’d have a longer study to see if they ended up with less cancer and one that just used swallowed tea components, since most people don’t finger-paint with tea in their mouths. And, we got just that.

As you can see at 2:15 in my video, there were the same extraordinary clinical results with some precancerous lesions shrinking away. What’s more, the study lasted long enough to see if fewer people actually got cancer. The answer? There was just as much new cancer in the green tea group as the placebo group. So, the tea treatment resulted in a higher response rate, as the lesions looked better, but there was no improvement in cancer-free survival.

These studies were done on mostly smokers and former smokers. What about lung cancer? As you can see at 2:46 in my video, population studies suggest tea may be protective, but let’s put it to the test. Seventeen patients with advanced lung cancer were given up to the equivalent of 30 cups of green tea a day, but “[n]o objective responses were seen.” In a study of 49 cancer patients, 21 of whom had lung cancer, the subjects received between 4 and 25 cups worth of green tea compounds a day. Once again, no benefits were found. The only benefit green tea may be able to offer lung cancer patients is to help lessen the burns from the radiation treatments when applied on the skin. Indeed, green tea compresses may be able to shorten the duration of the burns, as you can see at 3:21 in my video.

The protective effects of green tea applied topically were also seen in precancerous cervical lesions, where the twice-a-day direct application of a green tea ointment showed a beneficial response in nearly three-quarters of the patients, compared to only about 10 percent in the untreated control group, which is consistent with the benefits of green tea compounds on cervical cancer cells in a petri dish. When women were given green tea extract pills to take, however, they didn’t seem to help.

I talked about the potential benefit of green tea wraps for skin cancer in Treating Gorlin Syndrome with Green Tea, but is there any other cancer where green tea can come into direct contact? Yes. Colon cancer, which grows from the inner surface of the colon that comes into contact with food and drink. As you can see at 4:13 in my video, in the colon, tea compounds are fermented by our good gut bacteria into compounds like 3,4DHPA, which appears to wipe out colon cancer cells, while leaving normal colon cells relatively intact in vitro. So one hundred thirty-six patients with a history of polyps were randomized to get green tea extract pills or not. Now, this study was done in Japan, where drinking green tea is commonplace, so, effectively, this was comparing those who drank three cups of green tea a day to subjects who drank four daily cups. A year later on colonoscopy, the added-green tea group had only half the polyp recurrence and the polyps that did grow were 25 percent smaller. With such exciting findings, why hasn’t a larger follow-up study been done? Perhaps due to the difficulty “in raising funds” for the study, “because green tea is a beverage but not a pharmaceutical.”

There is good news. Thanks to a major cancer charity in Germany, researchers are currently recruiting for the largest green tea cancer trial to date, in which more than 2,000 patients will be randomized. I look forward to presenting the results to you when they come in.


What about prostate cancer? See my videos Preventing Prostate Cancer with Green Tea and Treating Prostate Cancer with Green Tea.

You may also be interested in these somewhat older videos:

How interesting was that about wisdom teeth? Green tea can also be used as an anti-cavity mouth rinse, which I discuss in my video What’s the Best Mouthwash?.

Is Caffeinated Tea Dehydrating? Watch the video to find out.

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:

What’s the Best Ferritin Level to Lower Cancer Risk?

If cancer is indeed a so-called ferrotoxic disease, a consequence, in part, of iron toxicity, that would explain not only the dramatic drop in cancer rates after blood donations, but also why people with higher levels of iron in their blood have an increased risk of dying from cancer, why women who bleed into their ovaries are at high risk for ovarian cancer, and why those suffering from hemochromatosis (an iron overload disease) have up to 200 times the risk of cancer. There has even been a call to go back and look at some of the chemotherapy trials that kept taking blood from the chemo group to check for side effects. Perhaps just the iron removal from the blood draws accounted for some of the apparent chemo benefits.

Iron may be a double-edged sword, as I explore in my video Donating Blood to Prevent Cancer?. Iron deficiency causes anemia, whereas excessive iron may increase cancer risk, presumably by acting as a pro-oxidant and generating free radicals. Iron-deficiency anemia is a serious problem in the developing world. “In meat-eating countries, however, iron excess may be more of a problem than iron deficiency…Body iron stores accumulate insidiously with ageing due to the fact that intake exceeds loss,” and our body has no good way of getting rid of excess iron.

Ferritin is a blood test measure of our backup iron stores. As you can see at 1:31 in my video, the normal range is about 12 to 200 ng/mL—but just because it’s normal doesn’t mean it’s ideal. In the blood donor study discussed earlier, those who developed cancer had ferritin levels around 127.1 ng/mL. The average for men may be over a hundred.

This suggests that so-called normal, “ambient levels of iron stores may be noxious and constitute a ‘public’ problem that affects large segments of the population.” As such, “[t]here may be a need to redefine the normal range…based on associated disease risk” rather than following a bell curve. “Thus, iron deficiency may exist when ferritin levels decline to less than about 12 ng/mL, whereas ferrotoxic disease may occur with levels greater than about 50 ng/mL.”

Harvard recently looked at blood donations and colorectal cancer, and found no connection, but the range of ferritin levels the researchers looking at was roughly 100 to less than 200 ng/mL, as you can see at 2:28 in my video. What’s more, those were from individuals who reported giving blood 30 or more times. So, perhaps instead of draining our blood to reduce excess iron stores, why not prevent the iron overload in the first place? If we measure the iron stores of men who stay away from heme iron and, instead, get all of their iron from plants, their iron levels are right around where the cancer-free donor group came in, as you can see at 2:54 in my video. This may help explain why those eating plant-based diets tend to have less cancer and other diseases associated with iron overload. Indeed, they may also have less pre-diabetes, as well as have less diabetes.


For more on the blood donor study I discussed, see Donating Blood to Prevent Heart Disease?.

For more on diet and iron levels, see The Safety of Heme vs. Non-Heme Iron and Risk Associated with Iron Supplements.

Interested in other examples of normal lab values not being necessarily ideal? Check out:

Even though a plant-based diet may be preferable for personal disease risk, that doesn’t mean we shouldn’t all give blood. Join me in supporting the Red Cross.

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: