Friday Favorites: Benefits of Turmeric for Arsenic Exposure

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Arsenic is a “carcinogenic heavy metal,” and “[t]he major mechanism of [arsenic]-related damage [appears to be] oxidative stress.” It’s the arsenic-induced “[a]ccumulation of free radicals” that can kill off cells, and damage our DNA. And then, the double whammy is that it may 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? As anyone familiar with my videos can attest, “numerous clinical [trials] have suggested…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, they suggest turmeric may both help scavenge free radicals as well as chelate, or bind up, heavy metals—complete with a fancy colorful diagram. But, it’s all just theory, until you put it to the test. Unfortunately, until recently, the tests were like this, where you can see if curcumin can protect against heavy metal-induced oxidation in puréed rat brains. 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.

In what became the greatest chemical disaster in human history, so-called “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 feet that looked like this, and as many as one in ten in some parts of the country will now go on to die from cancers caused by the arsenic exposure. This allowed the medical community to document all sorts of interesting cancers. But why not give them something that may help—like turmeric curcumin?

“After determining the [extent of] DNA damage, 50% of…volunteers were randomly selected and prescribed curcumin capsules blended with [a little black pepper compound],” and the other half “were…given a placebo.” Here’s the amount of DNA damage that was found in the curcumin and placebo groups of arsenic-exposed individuals before the study started, compared to the DNA damage found in a control group of individuals not exposed to arsenic, which remained the same throughout the study.

Now, they wanted to establish a baseline in the arsenic-exposed groups. So, they waited for three months to start the study. And, indeed, the DNA damage remained stable. Then, for three months, they proceeded to give them the curcumin or the placebo. The placebo didn’t do much, but within the first month, you 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.

And that’s amazing. The “curcumin had an effective role in [the] regression of DNA damage.” Yes, it’s “an excellent antioxidant agent,” but what they found subsequently is that the curcumin undid the arsenic crippling of our DNA repair enzymes. So, it both helped prevent the damage and facilitate repair. “Thus, curcumin…may be a useful modality for the prevention of arsenic-induced [cancer development].”

Of course, you have to make sure the turmeric itself isn’t contaminated with heavy metals. Oh, those poor kids in Bangladesh. If it’s not one thing, it’s  another. And, it’s not just kids in Bangladesh. 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 lead levels were not found to be statistically significant. How 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 you eat lots of healthy foods—like greens and sweet potatoes. Compared to those with low levels, those with high levels of beta carotene in their blood had 99% lower odds of getting arsenic-induced cancer—a hundred times lower odds. So, if you’re going to eat rice, why not some rice with some sweet potatoes on top?

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• Gulshan S, Rahman MJ, Sarkar R, Ghosh S, Hazra R. An Interesting Case of Basal Cell Carcinoma with Raynaud's Phenomenon Following Chronic Arsenic Exposure. JNMA J Nepal Med Assoc. 2016 Oct-Dec;55(204):100-102.
• Roy M, Sinha D, Mukherjee S, Biswas J. Curcumin prevents DNA damage and enhances the repair potential in a chronically arsenic-exposed human population in West Bengal, India. Eur J Cancer Prev. 2011 Mar;20(2):123-31.

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Image credit: Fight SLE. Image has been modified.

Motion graphics by Avocado Video.