How Much Arsenic in Rice Is Too Much?

What are some strategies to reduce arsenic exposure from rice?

Those who are exposed to the most arsenic in rice are those who are exposed to the most rice, like people who are eating plant-based, gluten-free, or dairy-free. So, at-risk populations are not just infants and pregnant women, but also those who may tend to eat more rice. What “a terrible irony for the health conscious” who are trying to avoid dairy and eat lots of whole foods and brown rice—so much so they may not only suffer some theoretical increased lifetime cancer risk, but they may actually suffer arsenic poisoning. For example, a 39-year-old woman had celiac disease, so she had to avoid wheat, barley, and rye, but she turned to so much rice that she ended up with sky-high arsenic levels and some typical symptoms, including “diarrhea, headache, insomnia, loss of appetite, abnormal taste, and impaired short-term memory and concentration.” As I discuss in my video How Much Arsenic in Rice Is Too Much, we, as doctors, should keep an eye out for signs of arsenic exposure in those who eat lots of rice day in and day out.

As you can see at 1:08 in my video, in its 2012 arsenic-in-rice exposé, Consumer Reports recommended adults eat no more than an average of two servings of rice a week or three servings a week of rice cereal or rice pasta. In its later analysis, however, it looked like “rice cereal and rice pasta can have much more inorganic arsenic—a carcinogen—than [its] 2012 data showed,” so Consumer Reports dropped its recommendation down to from three weekly servings to a maximum of only two, and that’s only if you’re not getting arsenic from other rice sources. As you can see from 1:29 in my video, Consumer Reports came up with a point system so people could add up all their rice products for the week to make sure they’re staying under seven points a week on average. So, if your only source of rice is just rice, for example, then it recommends no more than one or two servings for the whole week. I recommend 21 servings of whole grains a week in my Daily Dozen, though, so what to do? Get to know sorghum, quinoa, buckwheat, millet, oatmeal, barley, or any of the other dozen or so common non-rice whole grains out there. They tend to have negligible levels of toxic arsenic.

Rice accumulates ten times more arsenic than other grains, which helps explain why the arsenic levels in urine samples of those who eat rice tend to consistently be higher than those who do not eat rice, as you can see at 2:18 in my video. The FDA recently tested a few dozen quinoa samples, and most had arsenic levels below the level of detection, or just trace amounts, including the red quinoas that are my family’s favorite, which I was happy about. There were, however, still a few that were up around half that of rice. But, overall, quinoa averaged ten times less toxic arsenic than rice. So, instead of two servings a week, following the Consumer Reports recommendation, you could have 20. You can see the chart detailing the quinoa samples and their arsenic levels at 2:20 in my video.

So, diversifying the diet is the number-one strategy to reduce exposure of arsenic in rice. We can also consider alternatives to rice, especially for infants, and minimize our exposure by cooking rice like pasta with plenty of extra water. We found that a 10:1 water-to-rice ratio seemed best, though the data suggest the rinsing doesn’t seem to do much. We can also avoid processed foods sweetened with brown rice syrup. Is there anything else we can do at the dining room table while waiting for federal agencies to establish some regulatory limits?

What if you eat a lot of fiber-containing foods with your rice? Might that help bind some of the arsenic? Apparently not. In one study, the presence of fat did seem to have an effect, but in the wrong direction: Fat increased estimates of arsenic absorption, likely due to the extra bile we release when we eat fatty foods.

We know that the tannic acid in coffee and especially in tea can reduce iron absorption, which is why I recommend not drinking tea with meals, but might it also decrease arsenic absorption? Yes, by perhaps 40 percent or more, so the researchers suggested tannic acid might help, but they used mega doses—17 cups of tea worth or that found in 34 cups of coffee—so it isn’t really practical.

What do the experts suggest? Well, arsenic levels are lower in rice from certain regions, like California and parts of India, so why not blend that with some of the higher arsenic rice to even things out for everybody?

What?!

Another wonky, thinking-outside-the-rice-box idea involves an algae discovered in the hot springs of Yellowstone National Park with an enzyme that can volatize arsenic into a gas. Aha! Researchers genetically engineered that gene into a rice plant and were able to get a little arsenic gas off of it, but the rice industry is hesitant. “Posed with a choice between [genetically engineered] rice and rice with arsenic in it, consumers may decide they just aren’t going to eat any rice” at all.


This is the corresponding article to the 11th in a 13-video series on arsenic in the food supply. If you missed any of the first ten videos, watch them here:

You may also be interested in Benefits of Turmeric for Arsenic Exposure.

Only two major questions remain: Should we moderate our intake of white rice or should we minimize it? And, are there unique benefits to brown rice that would justify keeping it in our diet despite the arsenic content? I cover these issues in the final two videos: Is White Rice a Yellow-Light or Red-Light Food? and Do the Pros of Brown Rice Outweigh the Cons of Arsenic?.

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:

Açaí vs. Wild Blueberries for Artery Function

“Plant-based diets…have been found to reduce the risk of cardiovascular disease” and some of our other leading causes of death and disability. “Studies have shown that the longest living and least dementia-prone populations subsist on plant-based diets.” So why focus on açaí berries, just one plant, for brain health and performance?

Well, “foods rich in polyphenols…improve brain health,” and açaí berries contain lots of polyphenols and antioxidants, so perhaps that’s why they could be beneficial. If you’re only looking at polyphenols, though, there are more than a dozen foods that contain more per serving, like black elderberry, regular fruits like plums, flaxseeds, dark chocolate, and even just a cup of coffee.

As you can see at 1:02 in my video The Benefits of Açaí vs. Blueberries for Artery Function, in terms of antioxidants, açaí berries may have ten times more antioxidant content than more typical fruits, like peaches and papayas, and five times more antioxidants than strawberries. But blackberries, for instance, appear to have even more antioxidants than açaí berries and are cheaper and more widely available.

Açaí berries don’t just have potential brain benefits, however. Might they also protect the lungs against harm induced by cigarette smoke? You may remember the study where the addition of açaí berries to cigarettes protected against emphysema—in smoking mice, that is. That’s not very helpful. There is a long list of impressive-looking benefits until you dig a little deeper. For example, I was excited to see a “[r]eduction of coronary disease risk due to the vasodilation effect” of açaí berries, but then I pulled the study and found they were talking about a vasodilator effect…in the mesenteric vascular bed of rats. There hadn’t been any studies on açaí berries and artery function in humans until a study published in 2016.

Researchers gave overweight men either a smoothie containing about two-thirds of a cup of frozen açaí pulp and half a banana or an artificially colored placebo smoothie containing the banana but no açaí. As you can see at 2:26 in my video, within two hours of consumption of their smoothie, the açaí group had a significant improvement in artery function that lasted for at least six hours, a one or two point bump that is clinically significant. In fact, those walking around with just one point higher tend to go on to suffer 13 percent fewer cardiovascular events like fatal heart attacks.

As I show at 2:52 in my video, you can get the same effect from wild blueberries, though: about a one-and-a-half-point bump in artery function two hours after blueberry consumption. This effect peaks then plateaus at about one and a half cups of blueberries, with two and a half cups and three and a half cups showing no further benefits.

What about cooked blueberries? As you can see at 3:12 in my video, if you baked the blueberries into a bun, like a blueberry muffin, you get the same dramatic improvement in artery function.

Cocoa can do it, too. As shown at 3:30 in my video, after having one tablespoon of cocoa, you gain about one point, and two tablespoons gives you a whopping four points or so, which is double what you get with açaí berries.

One and a quarter cups’ worth of multicolored grapes also give a nice boost in artery function, but enough to counter an “acute endothelial insult,” a sudden attack on the vulnerable inner layer of our arteries? Researchers gave participants a “McDonald’s sausage egg breakfast sandwich and two hash browns.” They weren’t messing around! As you can see at 3:56 in my video, without the grapes, artery function was cut nearly in half within an hour, and the arteries stayed stiffened and crippled three hours later. But when they ate that McMuffin with all those grapes, the harmful effect was blunted.

Eat a meal with hamburger meat, and artery function drops. But if you eat that same meal with some spices, including a teaspoon and a half of turmeric, artery function actually improves.

What about orange juice? Four cups a day of commercial orange juice from concentrate for four weeks showed no change in artery function. What about freshly squeezed orange juice? Still nothing. That’s one of the reasons berries, not citrus, are the healthiest fruits.

For a beverage that can improve your artery function, try green tea. Two cups of green tea gives you that same effect we saw with cocoa, gaining nearly four points within just 30 minutes. And, as you can see at 5:05 in my video, that same crazy effect is also seen with black tea, with twice as powerful an effect as the açaí berries.

So, why all the focus on just that one plant? Why açaí berries? Well, the real reason may be because the author owns a patent on an açaí-based dietary supplement.


How do the antioxidant effects of açaí berries compare to applesauce? See The Antioxidant Effects of Açaí vs. Apples.

What about the effects of other foods on artery function? Coronary artery disease is, after all, our leading cause of death for men and women. See:

What else can blueberries do? Check 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:

Topical Green Tea for Acne and Fungal Infections

Which plant should we use for which skin disease? That’s the topic of my video Natural Treatment for Acne and Fungal Infections. Thousands of studies have been published to date about the health effects of green tea, but it wasn’t until fairly recently that researchers began to look at the possibility of using green tea for the prevention and treatment of infections. Patents have been taken out on the antibacterial, antifungal, and antiviral properties of tea. Let’s review some of the evidence.

In terms of fungal infections, green tea compounds have demonstrated “potent antifungal activity” against the primary cause of athlete’s foot, fungal nail infections, jock itch, and ringworm—comparable, in some cases, to powerful antifungal drugs like fluconazole. This was shown in a petri dish, though. How about a green tea footbath for athlete’s foot fungus between the toes? Evidently, tea leaves were once used as a folk remedy for the fungus, so why not put it to the test? Indeed, a once-a-day, 15-minute dilute green tea footbath led to a significant improvement in symptoms compared to controls.

Green tea baths also appeared to help with fungus-associated atopic dermatitis, though there was no control group in that study, and a full-strength green tea may help clear candida yeast from poorly cleaned dentures. What about the bacteria that cause plaque and gingivitis? Even a 2% green tea mouthwash was found to be effective. Yes, you should be able to control plaque just with proper brushing and flossing—with an emphasis on “proper.” Most people don’t brush for the recommended four minutes a day, so a dilute green tea mouthwash may help.

In terms of plaque bacteria-killing ability, green tea was beaten out by a “garlic with lime mouth rinse,” but I think I’ll just stick to green tea, especially when green tea appears to not only kill plaque bugs directly but also boost the antibacterial capacity of saliva after you drink it.

What about green tea for acne? Six weeks of a 2% green tea lotion cut the number of pimples by more than half and significantly reduced the severity, as you can see at 2:48 in my video, making it a cheap, effective treatment for acne.

Impetigo is another bacterial skin infection that can affect the face, but a tea ointment can affect an 80 percent cure rate, on par with antibiotics given topically or orally.

What about bladder infections? We know a certain concentration of green tea compounds can kill the type of E. coli that causes urinary tract infections. The question then becomes how much tea do you have to drink to achieve those concentrations in your bladder? Not much, it turns out. Just one cup of tea might have an effect, but you may need to space out multiple cups over the day because it gets cleared out of your system within about eight hours, as you can see at 3:45 in my video.

So, where do we stand now? The test tube data look promising, but there has yet to be a single study to put it to the test. At this point, green tea should just be used as an adjunct therapy for bladder infections. But, with emerging multidrug-resistant organisms, green tea certainly holds potential.

Wait a moment. If green tea is so good at killing bacteria, might we be killing the good bacteria in our gut when we drink it? No. That’s what’s so amazing. “It has also been shown that green tea has no effect over intestinal flora, which is a great advantage against other bactericidal [bacteria-killing] agents.” But that may not actually be true. Drinking green tea may actually boost the levels of our good bacteria by acting as a prebiotic, thereby improving the colon environment, so it may actually have some effect on our gut flora after all, but it appears to be all good.


Drinking tea with meals may impair iron absorption, so it’s better to drink it between meals. For more on green tea, one of my favorite beverages, along with water and hibiscus tea, see:

For more on acne, check 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:

Garlic Powder to Lower Lead Levels

There are so-called chelation drugs that can be taken for acute, life-threatening lead poisoning—for instance if your two-year-old swallowed one of the little lead weights her grandma was using while sewing curtains and the doctor happened to miss it on x-ray, so it stayed lodged inside her until she died with a blood lead level of 283 mcg/dcl, a case I discuss in my video Best Foods for Lead Poisoning: Chlorella, Cilantro, Tomatoes, Moringa?.

However, for lower grade, chronic lead poisoning, such as at levels under 45 μg/dL, there were no clear guidance as to whether these chelation drugs were effective. When they were put to the test, the drugs failed to bring down lead levels long term. Even when they worked initially, in dose after dose, the lead apparently continued to seep from the patients’ bones, and, by the end of the year, they ended up with the same lead levels as the sugar pill placebo group, as you can see at 0:50 in my video. It was no surprise, then, that even though blood lead levels dipped at the beginning, researchers found no improvements in cognitive function or development.

Since much of lead poisoning is preventable and the drugs don’t seem to work in most cases, that just underscores the need “to protect children from exposure to lead in the first place.” Despite the medical profession’s “best intentions to do something to help these kids…drug therapy is not the answer.” Yes, we need to redouble efforts to prevent lead poisoning in the first place, but what can we do for the kids who’ve already been exposed?

The currently approved method, these chelating drugs that bind and remove lead from our tissues, “lack[s]…safety and efficacy when conventional chelating agents are used.” So, what about dietary approaches? Plants produce phytochelatins. All higher plants possess the capacity to synthesize compounds that bind up heavy metals to protect themselves from the harmful effects, so what if we ate the plants? “Unlike other forms of treatment (e.g., pharmacotherapy with drugs), nutritional strategies carry the promise of a natural form of therapy that would presumably be cheap and with few to no side effects.” Yes, but would it work when the drugs didn’t?

We had learned that a meal could considerably cut down on lead absorption, but “the particular components of food intake that so dramatically reduce lead absorption” were uncertain at the time. Although the calcium content of the meal appeared to be part of it, milk didn’t seem to help and even made things worse. What about calcium supplements? Some assert that calcium supplements may help in reducing lead absorption in children, but “recommendations…must be based on evidence rather than conviction.” What’s more, those assertions are based in part on studies on rodents, and differences in calcium absorption and balance between rats and humans make extrapolation tricky. What you have to do is put it to the test. Researchers found that even an extra whopping 1,800 mg of calcium per day had no effect on blood lead levels. Therefore, the evidence doesn’t support conclusions that calcium supplements help.

What about whole foods? Reviews of dietary strategies to treat lead toxicity say to eat lots of tomatoes, berries, onions, garlic, and grapes, as they are natural antagonists to lead toxicity and therefore should be consumed on a regular basis. Remember those phytochelatins? Perhaps eating plants might help detoxify the lead in our own bodies or the bodies of those we eat.

These natural phytochelatin compounds work so well that we can use them to clean up pollution. For example, the green algae chlorella can suck up lead and hold onto it, so what if we ate it? If it can clean up polluted bodies of water, might it clean up our own polluted bodies? We don’t know, because we only have studies on mice, not men and women.

So, when you hear how chlorella detoxifies, they’re talking about the detoxification of rat testicles. Yes, a little sprinkle of chlorella might help your pet rat, or perhaps you could give them some black cumin seeds or give them a sprig of cilantro, but when you hear how cilantro detoxifies against heavy metals, I presume you don’t expect the researchers to be talking about studies in rodents. If we’re interested in science protecting our children, not just their pets, we’re out of luck.

The same is true with moringa, tomatoes, flaxseed oil, and sesame seed oil, as well as black grapes, and black, white, green, and red tea. There are simply no human studies to guide us.

Dietary strategies for the treatment of lead toxicity are often based on rodent studies, but, for tofu, at least, there was a population study of people that showed lower lead levels in men and women who ate more tofu. The researchers controlled for a whole bunch of factors, so it’s not as if tofu lovers were protected just because they smoked less or ate less meat, but you can’t control for everything.

Ideally, we’d have a randomized, placebo-controlled study. Researchers would take a group of people exposed to lead, split them into two groups, with half given food and the other half given some kind of identical placebo food, and see what happens. It’s easy to do this with drugs because you just use look-alike sugar pills as placebos so people don’t know which group they’re in, but how do you make placebo food? One way to do disguised food interventions is to use foods that are so potent they can be stuffed into a pill—like garlic. There had been various studies measuring the effects of garlic in rats and looking at garlic as a potential antidote for lead intoxication distributed among different mouse organs, but who eats mouse organs? One animal study did have some direct human relevance, though, looking at the effect of garlic on lead content in chicken tissues. The purpose was to “explore the possible use of garlic to clean up lead contents in chickens which”—like all of us on planet Earth—“had been exposed to lead pollution and consequently help to minimize the hazard” of lead-polluted chicken meat.

And…it worked! As you can see at 1:59 in my video Best Food for Lead Poisoning: Garlic, feeding garlic to chickens reduced lead levels in the “edible mass of chicken” by up to 75 percent or more. Because we live in a polluted world, even if you don’t give the chickens lead and raise them on distilled water, they still end up with some lead in their meat and giblets. But, if you actively feed them lead for a week, the levels get really high. When you give them the same amount of lead with a little garlic added, however, much less lead accumulates in their bodies.

What’s even more astonishing is that when researchers gave them the same amount of lead—but this time waited a week before giving them the garlic—it worked even better. “The value of garlic in reducing lead concentrations…was more pronounced when garlic was given as a post-treatment following the cessation of lead administration”—that is, after the lead was stopped and had already built up in their tissues. We used to think that “the beneficial effect of garlic against lead toxicity was primarily due to a reaction between lead and sulfur compounds in garlic” that would glom on to lead in the intestinal tract and flush it out of the body. But, what the study showed is that garlic appears to contain compounds that can actually pull lead not only out of the intestinal contents, but also out of the tissues of the body. So, the “results indicate that garlic contain chelating compounds capable of enhancing elimination of lead,” and “garlic feeding can be exploited to safeguard human consumers by minimizing lead concentrations in meat….”

If garlic is so effective at pulling lead out of chickens’ bodies, why not more directly exploit “garlic feeding” by eating it ourselves? Well, there had never been a study on the ability of garlic to help lead-exposed humans until…2012? (Actually, I’m embarrassed to say I missed it when the study was first published. That was back when I was just getting NutritionFacts.org up and running. Now that we have staff and a whole research team, hopefully important studies like this won’t slip through the cracks in the future.)

The study was a head-to-head comparison of the therapeutic effects of garlic versus a chelation therapy drug called D-penicillamine. One hundred and seventeen workers exposed to lead in the car battery industry were randomly assigned into one of two groups and, three times a day for one month, either got the drug or an eighth of a teaspoon of garlic powder compressed into a tablet, which is about the equivalent of two cloves of fresh garlic a day. As expected, the chelation drug reduced blood lead levels by about 20 percent—but so did the garlic. The garlic worked just as well as the drug and, of course, had fewer side effects. “Thus, garlic seems safer clinically and as effective,” but saying something is as effective as chelation therapy isn’t saying much. Remember how chelation drugs can lower blood levels in chronic lead poisoning, but they don’t actually improve neurological function?

Well, after treatment with garlic, significant clinical improvements were seen, including less irritability, fewer headaches, and improvements in reflexes and blood pressure, but these improvements were not seen in the drug group. They weren’t seen after treatment with the chelation therapy drug. So, garlic was safer and more effective. “Therefore, garlic can be recommended for the treatment of mild-to-moderate lead poisoning.


 There are also some human studieson vitamin C. Check out Can Vitamin C Help with Lead Poisoning?.

For even more lead videos, see:

To learn more about chlorella, 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:

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:

Boosting Antiviral Immune Function with Green Tea

Unlike most antiviral drugs, green tea appears to work by boosting the immune system to combat diseases such as genital warts (caused by HPV) and the flu (caused by the influenza virus).

According to one study, “The belief in green tea as a ‘wonder weapon’ against diseases dates back thousands of years.” I’ve talked about it in relation to chronic disease, but what about infectious disease? I explore this in my video Benefits of Green Tea for Boosting Antiviral Immune Function. Interest in the antimicrobial activity of tea dates back to a military medical journal in 1906, which suggested that servicemen fill their canteens with tea to kill off the bugs that caused typhoid fever. “However, this effect of tea was not studied further until the late 1980s” when tea compounds were pitted against viruses and bacteria in test tubes and petri dishes, but what we care about is whether it works in people. I had dismissed this entire field of inquiry as clinically irrelevant until I learned about tea’s effect on genital warts. External genital warts, caused by human wart viruses, “are one of the most common and fastest-spreading venereal diseases worldwide.”

Patients with external genital warts “present with one or several cauliflower-like growths on the genitals and/or anal regions…associated with…considerable impairment of patients’ emotional and sexual well-being.” But rub on some green tea ointment, and you can achieve complete clearance of all warts in more than 50 percent of cases.

If it works so well for wart viruses, what about flu viruses? As you can see at 1:41 in my video, it works great in a petri dish, but what about in people? Well, tea-drinking school children seem to be protected, but you don’t know about the broader population until it’s put to the test. If you give healthcare workers green tea compounds, they come down with the flu about three times less often than those given placebo, as you can see at 2:02 in my video. In fact, just gargling with green tea may help. While a similar effect was not found in high school students, gargling with green tea may drop the risk of influenza infection seven or eight-fold compared to gargling with water in elderly residents of a nursing home, where flu can get really serious.

Unlike antiviral drugs, green tea appears to work by boosting the immune system, enhancing the proliferation and activity of gamma delta T cells, a type of immune cell that acts as “a first line defense against infection.” According to the researchers, “Subjects who drank six cups of tea per day had up to a 15-fold increase in [infection-fighting] interferon gamma production in as little as one week”—but why?

There is in fact a molecular pattern shared by cancer cells, pathogens, and “edible plant products such as tea, apples, mushrooms, and wine.” So, eating healthy foods may help maintain our immune cells on ready alert, effectively priming our gamma delta T cells so they “then can provide natural resistance to microbial infections and perhaps tumors.” I guess I shouldn’t have been so surprised; tea, after all, is a “vegetable infusion.” You’re basically drinking a hot water extraction of a dark green leafy vegetable.


For more on what green tea can (and cannot) do, check out videos such as:

How else can we improve our immune function? See, for example:

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 to Take for Menstrual Cramps

In my video Ginger for Migraines, I described how ginger works as well as the leading “drug” in the treatment of migraines, “one of the most common causes of pain syndromes,” affecting as much as 12 percent of the population. Twelve percent is “common”?

How about menstrual cramps, which plague up to 90 percent of younger women? You can tell this study was written by a guy because he emphasizes the absenteeism and all the “lost productivity” for our nation. Menstrual cramps also just really hurt.

Can ginger help? As I discuss in my video Benefits of Ginger for Menstrual Cramps, women took a quarter teaspoon of ground ginger powder three times a day during the first three days of menstruation, and pain dropped from seven on a scale of one to ten down to a five, whereas there was no significant change in the placebo group, as you can see at 0:56 in my video. Most women in the placebo group said their symptoms stayed the same, whereas those unknowingly in the ginger group said they felt much better.

A subsequent study found that even just an eighth of a teaspoon three times a day appeared to work just as well, dropping pain from an eight to a six and, in the second month, down to a three. The “alleviation of menstrual pain was more remarkable during the second month of the intervention,” and study participants had only been taking the ginger for four days, not the whole month, suggesting it might work even better if women use ginger every period. 

What about the duration of pain? As you can see at 1:52 in my video, a quarter teaspoon of ground ginger powder three times a day not only dropped the severity of pain from about a seven down to a five but also decreased the duration of total hours in pain from 19 hours down to about 15 hours, indicating that three quarters of a teaspoon of ginger powder a day for three days is a safe and effective way to produce pain relief in college students with painful menstrual cramps, compared to placebo, capsules filled instead with powdered toast. But women don’t take breadcrumbs for their cramps. How does ginger compare with ibuprofen? An eighth of a teaspoon of ginger powder four times a day for three days versus 400 milligrams of Motrin were put to the test, and the ginger worked just as well as the drug of choice, as you can see at 2:40 in my video.

If you do take the drug, though, I was surprised to learn that it may be better to take drugs like ibuprofen and naproxen on an empty stomach because that may speed up the pain relief and help keep people from taking higher doses.


I’ve touched on this effect before in Ginger for Nausea, Menstrual Cramps, and Irritable Bowel Syndrome. What else can this amazing plant do? See, for example:

What else can really help with cramps, PMS, and cyclical breast pain? Check 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:

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: