Benefits of Turmeric for Arsenic Exposure

What happened when turmeric curcumin was put to the test to see if it could reverse DNA damage caused by arsenic exposure?

Arsenic is a carcinogenic heavy metal, and the major mechanism of arsenic-related damage appears to be oxidative stress. It’s the arsenic-induced accumulation of free radicals that can kill off cells and damage our DNA, and the double whammy is that it may also disrupt our body’s ability to repair our DNA once it’s damaged. Well, if the damage is oxidation, what about eating antioxidant-rich foods, such as the spice turmeric, which contains an antioxidant pigment known as curcumin. I examine this in my video Benefits of Turmeric for Arsenic Exposure.

As anyone familiar with my videos can attest, “numerous clinical studies have suggested that curcumin has therapeutic efficacy against a variety of human diseases,” including cancer, diabetes, Alzheimer’s, and inflammatory bowel, joint, lung, skin, and eye diseases.

In terms of protection against heavy metals, studies suggest turmeric may help scavenge free radicals, as well as chelate, or bind up, heavy metals. But it’s all just theory, until you put it to the test. Until recently, all we had was research studying whether curcumin can protect against heavy metal-induced oxidation in puréed rat brains, for example. Why can’t you just give some turmeric to people? It’s not like there aren’t millions of people out there who’ve been exposed to arsenic and could use some help.

Indeed, in what became the greatest chemical disaster in human history, “tube-wells” were installed in Bangladesh to provide clean water. UNICEF meant well—too bad they didn’t test the water for arsenic. People started showing up with lesions on their feet, as you can see at 1:52 in my video, and as many as one in ten people in some parts of the country will now go on to die from cancers caused by the arsenic exposure. This disaster allowed the medical community to document all sorts of “interesting” cancers, but why not give them something that may help, like turmeric curcumin?

Researchers did just that. After they determined the extent of DNA damage in study subjects, half were randomly selected and prescribed curcumin capsules blended with a little black pepper compound, while the other half were given a placebo. As you can see at 2:25 in my video, before the study started, the amount of DNA damage found in the curcumin and placebo groups of arsenic-exposed individuals was higher than the DNA damage found in a control group of individuals not exposed to arsenic, which remained the same throughout the study. The researchers wanted to establish a baseline in the arsenic-exposed groups, so they waited for three months before starting the study. And, indeed, the DNA damage remained stable during that time. Then, for three months, they proceeded to give the groups the curcumin or the placebo. The placebo didn’t do much, but within the first month, the researchers could see the curcumin working. And, by the third month, the DNA damage in the curcumin-treated arsenic group was no worse than in those who hadn’t been exposed to arsenic at all. Amazing! “The comparison of the populations receiving curcumin and placebo established that curcumin had an effective role in regression of DNA damage and as an excellent antioxidant agent,” and what they found subsequently is that the curcumin undid the arsenic crippling of our DNA repair enzymes—both helping to prevent the damage and facilitating its repair. “Thus, curcumin intervention may be a useful modality for the prevention of arsenic-induced carcinogenesis [cancer development].”

Of course, you have to make sure the turmeric itself isn’t contaminated with heavy metals. Nearly a quarter of spices purchased in Boston had lead in them, and it’s not just a matter of buying U.S. versus foreign brands, as the difference in lead levels was not found to be statistically significant, as you can see at 3:52 in my video.

What about just eating antioxidant-rich fruits and vegetables? The reason we care about DNA damage is that we care about cancer. What if you measured the beta-carotene levels in people exposed to arsenic who went on to develop cancer, compared to those who got exposed to the same amount of arsenic but didn’t get cancer? Beta-carotene is like a proxy for healthy fruit and vegetable intake. The way you get high levels in your blood is by eating lots of healthy foods, like greens and sweet potatoes. Compared to those with low levels of beta-carotene in their blood, those with high levels had 99 percent lower odds of getting arsenic-induced cancer, as you can see at 4:34 in my video. So, if you’re going to eat rice, why not have some rice with some sweet potatoes on top?


What’s the rice connection? I produced a 13-part series on arsenic in rice. Air-pop some popcorn, sit back, and enjoy:

What else can turmeric do? Glad you asked!

Who Shouldn’t Consume Curcumin or Turmeric? 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 About Coconuts, Coconut Milk, and Coconut Oil MCTs?

Do the medium-chain triglycerides in coconut oil and the fiber in flaked coconut counteract the negative effects on cholesterol and artery function?

Studies of populations who eat a lot of coconuts are “frequently cited” by those who sell coconut oil “as evidence that coconut oil does not have negative effects on cardiovascular health.” For example, there was an apparent absence of stroke and heart disease on the island of Kativa in Papua New Guinea. What were they eating? Their diets centered around tubers, like sweet potatoes, with fruits, greens, nuts, corn, and beans. Although they ate fish a few times a week, they were eating a largely whole food plant-based diet. It’s no wonder they may have had such low rates of artery disease. And, one of the whole foods they were eating was coconut, not coconut oil.

Now, if you go to Pukapuka, even more coconuts are eaten. In fact, as you can see at 0:51 in my video What About Coconuts, Coconut Milk, and Coconut Oil MCTs?, there’s even an island where coconuts make up most of what people eat—and they do get high cholesterol. How can a population eating 87 percent plant-based, with no dairy and only rare consumption of red meat, chicken, and eggs, have cholesterol levels over 200? Well, they’re eating all those coconuts every day. What are their disease rates like? We don’t know. There are no clinical surveys, no epidemiological death data, and no autopsies. Some EKGs were taken, which can sometimes pick up evidence of past heart attacks, but they found few abnormalities. The sample was too small to be a definitive study, though. And, even if they did have low disease rates, they weren’t eating coconut oil—they were eating coconut in its whole form.

Coconut oil proponents pointing to these studies is like the high fructose corn syrup lobby pointing to studies of healthy populations who eat corn on the cob or the sugar industry pointing to studies on fruit consumption and saying you can eat all the refined sugar you want. But fruit has fiber and so do coconuts. Just as adding psyllium fiber (Metamucil) to coconut oil can help blunt the adverse effects on cholesterol, fiber derived from defatted coconut itself can reduce cholesterol levels as much as oat bran. What’s more, the plant protein in coconuts, which is also missing from the oil, may help explain why whole coconuts may not have the same effects on cholesterol. Although coconut fat in the form of powdered coconut milk may not have the same effects on cholesterol as coconut oil, frequent consumption, defined as three or more times a week, has been associated with increased risk of vascular disease, stroke, and heart disease. And, no wonder, as coconut milk may acutely impair artery function as badly as a sausage and egg McMuffin.

Researchers tested three different meals including a Western high-fat meal that “consisted of an Egg McMuffin®, Sausage McMuffin®, 2 hash brown patties and a non-caffeinated beverage (McDonald’s Corporation)” a local high-fat meal, and an “isocaloric low-fat meal.” The study was conducted in Singapore, so the more traditional local high-fat meal was rice cooked in coconut milk and served with anchovies and an egg. These two different high-fat meals were put up against the same amount of calories in an unhealthy low-fat meal of Frosted Flakes, skim milk, and juice. At 3:21 in my video, you can see the artery function—that is, its ability to relax normally—before and after eating each of the three meals. Researchers found that artery function is significantly crippled within hours of consuming the McMuffins and also the local high-fat meal with coconut milk. So, whether the fat is mostly from meat and oil or from coconut milk, the arteries clamped down similarly, whereas that horrible sugary breakfast had no bad effect on artery function. Why? Because as terrible as the Frosted Flakes meal was, it had no saturated fat at all. (It also didn’t have contain any eggs, so that might have helped, too.)

Coconut oil proponents also try to argue that coconut oil has MCTs, medium-chain triglycerides, which are shorter-chain saturated fats that aren’t as bad as the longer-chain saturated fats in meat and dairy. You can’t apply the MCT research to coconut oil, though. Why not? Well, MCT oil is composed of MCTs—about 50 percent of the medium-chain fat caprylic acid and the other 50 percent of the MCT capric acid—whereas those MCTs make up only about 10 percent of coconut oil. Most of coconut oil is the cholesterol-raising, longer-chain saturated fats, lauric and myristic. “It is therefore inaccurate to consider coconut oil to contain either predominantly medium-chain fatty acids or predominantly medium-chain triglycerides. Thus, the evidence on medium-chain triglycerides cannot be extrapolated to coconut oil.”

It’s actually quite “a common misconception” that the saturated fat in coconut oil is comprised of mainly MCTs. Actually, as we discussed, coconut oil is mainly lauric and myristic, both of which have potent bad LDL cholesterol-raising effects. “Coconut oil should therefore not be advised for people who should or want to reduce their risk of CHD,” coronary heart disease, which is the number-one killer of U.S. men and women. The beef industry, for example, loves to argue that beef fat contains stearic acid, a type of saturated fat that doesn’t raise cholesterol. Yes, but it also has palmitic and myristic acids that, like lauric acid, do raise cholesterol, as you can see at 5:12 in my video.

If you compare the effects of different saturated fats, as you can see at 5:29 in my video, stearic acid does have a neutral effect on LDL, but palmitic, myristic, and lauric acids shoot it up—and, frankly, so may MCT oil itself, as it bumps up LDL 15 percent compared to control. Bottom line? “Popular belief”—spread by the coconut oil industry—“holds that coconut oil is healthy, a notion not supported by scientific data.” The science just doesn’t support it.

So, basically, “coconut oil should be viewed no differently” from animal sources of dietary saturated fat. A recent review published in the Journal of the American College of Cardiology put it even more simply in its recommendations for patients. When it comes to coconut oil, “avoid.”

Okay, but doesn’t saturated fat boost HDL, the so-called good cholesterol? Check out Coconut Oil and the Boost in HDL “Good” Cholesterol.


Isn’t coconut oil supposed to be good for Alzheimer’s, though? See my video Does Coconut Oil Cure Alzheimer’s?

If you want to learn more about the original McMuffin artery studies, see The Leaky Gut Theory of Why Animal Products Cause Inflammation.

You may also be interested in Flashback Friday: Coconut Oil and Abdominal Fat.

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:

How to Lower Your Sodium-to-Potassium Ratio

The potassium content in greens is one of two ways they can improve artery function within minutes of consumption.

More than a thousand years ago, for the treatment of hypertension, an ancient Persian medical text advised lifestyle interventions, such as avoiding meat and pastries, and recommended eating spinach. A thousand years later, researchers discovered that a single meal containing spinach could indeed reduce blood pressure, thanks to its nitrate content. All green leafy vegetables are packed with nitrate, which our body can use to create nitric oxide that improves the flexibility and function of our arteries. This may be why eating our greens may be one of the most powerful things we can do to reduce our chronic disease risk.

As you can see at 0:54 in my video Lowering Our Sodium-to-Potassium Ratio to Reduce Stroke Risk, just switching from low-nitrate vegetables to high-nitrate vegetables for a week can lower blood pressure by about 4 points, and the higher the blood pressure people started out with, the greater benefit they got. Four points might not sound like a lot, but even a 2-point drop in blood pressure could prevent more than 10,000 fatal strokes every year in the United States.

Potassium-rich foods may also act via a similar mechanism. If we get even just the minimum recommended daily intake of potassium, we might prevent 150,000 strokes every year. Why? Potassium appears to increase the release of nitric oxide. One week of eating two bananas and a large baked potato every day significantly improved arterial function. Even a single high-potassium meal, containing the equivalent of two to three bananas’ worth of potassium, can improve the function of our arteries, whereas a high-sodium meal—that is, a meal with the amount of salt most people eat—can impair arterial function within 30 minutes. While potassium increases nitric oxide release, sodium reduces nitric oxide release. So, the health of our arteries may be determined by our sodium-to-potassium ratio.

As you can see at 2:30 in my video, after two bacon slices’ worth of sodium, our arteries take a significant hit within 30 minutes. However, if you add three bananas’ worth of potassium, you can counteract the effects of the sodium. As I show at 2:48 in my video, when we evolved, we were eating ten times more potassium than sodium. Now, the ratio is reversed, as we consume more sodium than potassium. These kinds of studies “provide additional evidence that increases in dietary potassium should be encouraged,” but what does that mean? We should eat more beans, sweet potatoes, and leafy greens, the latter of which is like giving you a double whammy, as they are high in potassium and nitrates. The recommendation from a thousand years ago to eat spinach is pretty impressive, though bloodletting and abstaining from sex were also encouraged, so we should probably take ancient wisdom with a grain of salt—but our meals should be added-salt free.

Why might abstaining from sex not be the best idea for cardiovascular health? Because the opposite may actually be true. See my video Do Men Who Have More Sex Live Longer?.


What else can we do about stroke risk? Check out:

For more on potassium, see in Potassium and Autoimmune Disease and 98% of American Diets Potassium-Deficient.

Interested in learning more about the dangers of sodium? See:

Sodium isn’t just bad for our arteries. Check out How to Treat Asthma with a Low-Salt Diet and Sodium and Autoimmune Disease: Rubbing Salt in the Wound?.

I further explore the wonders of nitrate-rich vegetables in:

Sweet potatoes are an excellent high-potassium, low-sodium choice, but what’s the best way to prepare them? Check out The Best Way to Cook Sweet Potatoes.

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: