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Can Vitamin C Supplements Help with Lead Poisoning?

“Even if a nutritional manipulation is proven effective in reducing blood lead levels, reliance on such an intervention places most of the burden for prevention on those most affected and least responsible for the underlying environmental causes of lead toxicity. Nutritional interventions, therefore, must never substitute for efforts to reduce lead exposure to safe levels. On the other hand, when used as an adjunct to environmental measures, some nutritional changes may prove to have benefits beyond any impact on lead toxicity.” For example, consumption of vitamin C-rich foods may help with “blood pressure, blood lipid profiles, and respiratory symptoms,” in addition to perhaps influencing “lead toxicity through an influence on absorption of lead, elimination of lead, transport within the body, tissue binding, or secondary mechanisms of toxicity,” that is, even just helping ameliorate some of the damage. But what is this based on?

In 1939, a remarkable study was published, entitled “Vitamin C treatment in lead poisoning,” in which 17 lead industry workers were given 100 mg of vitamin C a day, the amount found in one or two oranges, and “with practically all of them there was a marked gain in vigor, color of skin, cheerfulness, blood picture, appetite and ability to sleep well.” The 17 workers were chosen because they seemed to be in pretty bad shape and possibly even had scurvy, so it’s no wonder a little vitamin C helped. But vitamin C is an antioxidant, and oxidation is “an important mechanism underlying lead toxicity,” so it’s conceivable that it may have mediated some of the harm. But, the vitamin C didn’t appear to just reduce the damage from the lead—it also reduced the lead itself. As you can see from 1:43 in my video Can Vitamin C Help with Lead Poisoning?, the amount of lead in a painter’s urine over a period of a month after starting 200 mg of vitamin C a day exhibited a five-fold drop, suggesting he was absorbing less of the lead into his body. He was one of three painters researchers tried this on, and evidently all three painters’ levels dropped. The researchers concluded that those “exposed to lead…should be advised to include in their diet plenty of such rich sources of vitamin C as tomatoes (fresh or canned), raw cabbage, oranges or grapefruit, raw spinach (or even cooked, in very little water), raw turnips, green bell peppers, cantaloupe, etc.”

Now, this drop in lead in the subjects’ urine was seen with only three painters, and the study didn’t have a control group of painters who didn’t take vitamin C, so perhaps everyone’s lead levels would have dropped for some other reason or perhaps it was just a coincidence. You don’t know…until you put it to the test.

Those original data were so compelling that others were inspired to try to replicate them. I mean, if it actually worked, if vitamin C could help with lead poisoning, grapefruits could be handed out at the factory door! The earlier study didn’t have a good control group, but the researchers weren’t going to make that same mistake this time. In this study, half of the group got 100 mg of vitamin C a day—not just for a month but for a year—and the other group got nothing. The result? “Careful study of a large group of lead workers failed to reveal any effect of ascorbic acid vitamin C…on the lead concentration in the blood…or urine” (emphasis added). There was no difference in their physical condition and no changes in their blood work, so “no reason has been found for recommending the use of ascorbic acid vitamin C to minimize effects of lead absorption.” What a disappointment. It looked so promising!

Whenever I study a topic, I try to read the research chronologically so I can experience the discoveries as they happened throughout history. At this point, though, I was so tempted to jump to a recent review to see what had happened in the intervening 74 years since that first study was published, but I didn’t want to spoiler alert! myself, so I kept reading the papers sequentially. There were in vitro studies where researchers dripped antioxidants on lead exposed cells and it seemed to help, so they jumped on the cantaloupe bandwagon, too, but these were test tube studies.

The first population study was published in 1999, and, as you can see at 4:02 in my video, researchers did find that those with high vitamin C levels in their blood tended to have lower lead levels. Youths with the highest vitamin C levels had a nearly 90 percent lower prevalence of elevated blood lead levels compared to those with the lowest vitamin C levels. Now, this was a cross-sectional study, just a snapshot in time, so we don’t know if the vitamin C caused a drop in lead or if perhaps the lead caused a drop in vitamin C. Lead is a pro-oxidant, so maybe it ate up the vitamin C. And who has higher vitamin C levels? Those who can afford to have higher vitamin C levels and eat lots of fruits and vegetables. “It is also possible that higher ascorbic acid levels may represent healthier lifestyles or greater socio-economic status.” Indeed, maybe lower vitamin C levels are just a proxy for being poor, and that’s the real reason for higher lead levels.

There are lots of good reasons to be eating more fruits and vegetables, and we should be eating more spinach regardless, but it would be nice to know if vitamin C actually helps with lead poisoning. And, to know that, we need to put it to the test.

Unfortunately, most of the published interventions are not very helpful, with such titles as “Effects of dietary vitamin C supplementation on lead-treated sea cucumbers,….”  And, there is a surprising number of articles on the effects of vitamin C supplementation on mouse testicles. Why? Because lead may impair male fertility. Indeed, lead workers appear to have a reduced likelihood of fathering children, but this may in part be due to oxidative stress. In that case, how about giving an antioxidant, like vitamin C, and putting it to the test(es)? No, I’m not talking about rat testes or suggesting frog testes. Neither am I proposing crab testes. (I didn’t even know crabs had testicles!) Finally, here’s one to discuss: “Clinical relevance of vitamin C among lead-exposed infertile men.” A study of human men, which I will cover in Yellow Bell Peppers for Male Infertility and Lead Poisoning?.

I’m always conflicted about writing these kinds of blogs and producing videos like Can Vitamin C Help with Lead Poisoning?. I can imagine some just want “the answer,” but those with vested and commercial interests often exploit that natural impulse. This is problem with science in general, but perhaps particularly in nutrition. When it comes to something as life-or-death important as what to feed ourselves and our families we shouldn’t just follow someone’s opinions or beliefs on the matter. We should demand to see the science. That’s what I try to do: Present the available data as fairly and even-handedly as possible, and let you make up your own mind. You can imagine how easily someone could cherry-pick just one or two studies and present a distorted but compelling case for or against, in this case, vitamin C supplements. That’s why I feel it’s important to present each study in their historical context. Stay tuned for the thrilling conclusion in Yellow Bell Peppers for Male Infertility & Lead Poisoning?.


 For those of you who are thinking, Why should I care about lead? I don’t eat paint chips or use leaded gasoline. Anyway, what’s the big deal?, check out my full series of lead videos for information on how we got into this mess and some of the ways we can dig ourselves 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:

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Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.


8 responses to “Can Vitamin C Supplements Help with Lead Poisoning?

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  1. Smiling. A blog with a cliffhanger.

    Link attached for the people who can’t handle cliffhangers.

    I love that you share the whole process. It helps my brain so much.

  2. I was looking at ionic footbaths on PubMed yesterday. The studies weren’t really there for it as a form of detox but it did seem to decrease aluminum, arsenic, and mercury. Not lead. Pretty sure, not lead.

    I was comparing that to 12 weeks of Fiji water in price and effectiveness.

  3. Off topic my husband was in hospital with chest pains. Turns out it wasn’t his heart but pain in his esophagus. They fed him milk and eggs! When will hospitals wake up to nutrition? Luckily we are in Canada so no bills to pay.

  4. DEB – ABOUT SILAGE:

    I’ve been told by farmers that feeding corn or wheat even once to ruminants does something to the rumen, reducing the amount of certain nutrients in the animal. Perhaps this makes more sense when we remember that Dr. Greger has reported that, in humans, eating different foods changes the bacteria in our intestines.

    But to produce conjugated linoleic acid (CLA – reputed to have many (unproven) health benefits in humans), the bacteria in the rumen must consume FRESH grass, because as soon as the grass starts to dry, the enzymes in the grass needed by the bacteria start breaking up. So what farmers (of 100% grass fed ruminant) do is wrap up newly cut grass in plastic to prevent the grass from drying – producing SILAGE. That is what ruminants eat in winter. The problem with this (according to one farmer) is you end up with a giant icicle.

    I am not familiar with the other terms in your post. Where did they come from?

    I know there was a big meeting a few years back when farmers got together to come up with a definition of just what is 100% grass fed ruminant. There was a lot of discussion and arguing about what do we feed the animals in an emergency? So a rule was added that there has to be enough stored silage to last through an emergency.

    I also know that not all farmers were happy with rules finally issued by the feds. Further, some farmers have been experimenting with planting a small amount of legumes, etc.

    So finally: it is best to buy 100% grass beef and lamb from a southern farmer so the fields are buried in snow much less of the time.

  5. There is a conundrum in the research on Vitamin C. First, Ascorbic acid is an extract from an environment (the whole fruit or vegetable) containing many other nutrients, such as flavonoids and antioxidants along with other vitamins and minerals, that affect the efficacy of “Vitamin C.” So, studies comparing the vitamin C in a red bell pepper or a grapefruit cannot logically or practically be compared to studies focusing simply on Ascorbic Acid and calling that ascorbic Acid Vitamin C and the grapefruit as a vitamin C source. I must say emphatically that this note is not a negative review of Dr. Greger’s article or work, it is for the scientific research community as a whole. Ascorbic acid by itself can never have the same effect in the human body as the nutritional profile of a Vitamin C laden fruit or vegetable. All of the research makes this mistake. I would like to see research that lists, let’s say, 75 to 100% of the nutrients or the perfect nutritional profile of an orange, let’s say, and determine their effects on the human body. Since all fruits and vegetables contain hundreds of nutrition co-factors or nutrients, perhaps the four or five leading nutrients in say an orange or other fruit or vegetable could be researched for “their”, effects, let’s say, on lead poisoning or lead content in urine of workers.

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