Iron, zinc, oil, and even doughnuts are put to the test to see if they can block lead absorption.
How to Lower Lead Levels with Diet: Thiamine, Fiber, Iron, Fat, Fasting?
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.
There are certain nutrients whose intake has been associated with lower lead levels in the body. For example, women with higher thiamine intake (vitamin B1 intake) tended to have lower blood lead levels; the same with lead-exposed steel workers. Fiber and iron intake were also associated, to a lesser degree, with lower lead levels in the blood. The thinking is that the fiber might glom onto the lead, and flush it out of the body. And, the iron would inhibit the lead absorption, whereas the thiamine may accelerate lead removal through the bile. Thus, the research suggests that eating lots of iron, fiber, and especially thiamine-rich foods “may induce rapid removal and excretion of…lead from the tissues.” But thiamine’s never been put to the test, where you give people thiamine, and see if their lead levels drop. The closest I could find is a thiamine intervention for lead-intoxicated goats.
And, much of the fiber data are just from test tube studies like this, where, under simulated intestinal conditions, complete with flasks of feces, both soluble and insoluble dietary fiber were able to bind up large amounts of mercury, cadmium, and lead to such an extent that they may have blocked absorption in the small intestine—though when our good gut flora then might eat the fiber, some of the heavy metals may be re-released in the colon. So, it’s not completely fail-safe, and, like thiamine, there haven’t been controlled human studies.
But look, where is thiamine found? Here’s some of the healthiest sources that also contain fiber, concentrated in super-healthy foods like beans and greens that we should all be eating anyway. So, even if thiamine and fiber-rich foods don’t actually lower your lead levels, you’d still end up healthier.
Iron was put to the test, though, and it failed to improve the “cognitive performance” of lead-exposed children, failed to improve “behavior” or ADHD symptoms. No surprise, because it failed to bring down lead levels, as did zinc supplementation. Turns out that while “iron may limit [the] absorption of lead,…it may also inhibit [the] excretion of…lead” that’s already in your body.
And, iron may not even inhibit lead absorption in the first place. That was based on rodent studies, and it turns out we’re not rodents.
Same story with zinc. It may have helped to protect rat testicles, but didn’t seem to help human children. “Nevertheless, iron is routinely prescribed in children with lead poisoning.” But, “[G]iven the lack of scientific evidence supporting the use of [indiscriminate] iron [supplementation] in… children with lead poisoning, its routine use should be reexamined.” Though obviously, if you have an iron deficiency, supplementation may help.
High fat intake has also been identified as something that make things worse for lead-exposed children. Dietary fat was associated with higher lead levels in a cross-sectional, snapshot-in-time study, and there is a plausible biological mechanism. Dietary fat may boost lead absorption by stimulating extra bile, which, in turn, may “contribute…to lead absorption.” But, you really don’t know until you put it to the test.
In addition to testing iron, they also tested fat. They gave a group of intrepid volunteers a cocktail of radioactive lead. Then, with a Geiger counter, they could measure how much radiation they retained in their bodies. Drinking the lead with iron or zinc didn’t change anything, but adding about two teaspoons of vegetable oil boosted lead absorption into the body from about 60% up to around 75%.
The only thing that seemed to help, dropping lead absorption down to about 40%, was eating a light meal with the lead drink. What was the meal? Coffee and a doughnut. I think this is the first doughnut intervention I’ve ever seen with a positive outcome. Could it have been the coffee? Unlikely, as, if anything, coffee drinking has been associated with a tiny increase in blood levels.
If fat makes things worse, and the one sugar they tried didn’t help, they figured that it was just “eating food”—any food—not taking in lead on an empty stomach, that made the difference. And, indeed, if you repeat the study with a whole meal, lead absorption doesn’t just drop from 60% to 40%, but all the way down to just 4%! That’s extraordinary. That means it’s 15 times worse to ingest lead on an empty stomach.
Please consider volunteering to help out on the site.
- Campbell C, Osterhoudt KC. Prevention of childhood lead poisoning. Curr Opin Pediatr. 2000 Oct;12(5):428-37.
- Mahaffey KR. Nutrition and lead: strategies for public health. Environ Health Perspect. 1995 Sep;103 Suppl 6:191-6.
- James HM, Hilburn ME, Blair JA. Effects of meals and meal times on uptake of lead from the gastrointestinal tract in humans. Hum Toxicol. 1985 Jul;4(4):401-7.
- Rosado JL, López P, Kordas K, García-Vargas G, Ronquillo D, Alatorre J, Stoltzfus RJ. Iron and/or zinc supplementation did not reduce blood lead concentrations in children in a randomized, placebo-controlled trial. J Nutr. 2006 Sep;136(9):2378-83.
- Kordas K, Stoltzfus RJ, López P, Rico JA, Rosado JL. Iron and zinc supplementation does not improve parent or teacher ratings of behavior in first grade Mexican children exposed to lead. J Pediatr. 2005 Nov;147(5):632-9.
- Batra N, Nehru B, Bansal MP. The effect of zinc supplementation on the effects of lead on the rat testis. Reprod Toxicol. 1998 Sep-Oct;12(5):535-40.
- Flanagan PR, Chamberlain MJ, Valberg LS. The relationship between iron and lead absorption in humans. Am J Clin Nutr. 1982 Nov;36(5):823-9.
- Wright RO. The role of iron therapy in childhood plumbism. Curr Opin Pediatr. 1999 Jun;11(3):255-8.
- Lucas SR, Sexton M, Langenberg P. Relationship between blood lead and nutritional factors in preschool children: a cross-sectional study. Pediatrics. 1996 Jan;97(1):74-8.
- Ou S, Gao K, Li Y. An in vitro study of wheat bran binding capacity for Hg, Cd, and Pb. J Agric Food Chem. 1999 Nov;47(11):4714-7.
- Taylor CM, Golding J, Hibbeln J, Emond AM. Environmental factors predicting blood lead levels in pregnant women in the UK: the ALSPAC study. PLoS One. 2013 Sep 5;8(9):e72371.
- Lee MG, Chun OK, Song WO. Determinants of the blood lead level of US women of reproductive age. J Am Coll Nutr. 2005 Feb;24(1):1-9.
- Ito Y, Niiya Y, Otani M, Sarai S, Shima S. Effect of food intake on blood lead concentration in workers occupationally exposed to lead. Toxicol Lett. 1987 Jul;37(2):105-14.
- Rico JA, Kordas K, López P, Rosado JL, Vargas GG, Ronquillo D, Stoltzfus RJ. Efficacy of iron and/or zinc supplementation on cognitive performance of lead-exposed Mexican schoolchildren: a randomized, placebo-controlled trial. Pediatrics. 2006 Mar;117(3):e518-27.
Icons created by Anand Prahlad, Jon Trillana and Imogen Oh from the Noun Project.
Image credit: Kristina DeMuth. Image has been modified.
Motion graphics by Avocado Video.
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.
There are certain nutrients whose intake has been associated with lower lead levels in the body. For example, women with higher thiamine intake (vitamin B1 intake) tended to have lower blood lead levels; the same with lead-exposed steel workers. Fiber and iron intake were also associated, to a lesser degree, with lower lead levels in the blood. The thinking is that the fiber might glom onto the lead, and flush it out of the body. And, the iron would inhibit the lead absorption, whereas the thiamine may accelerate lead removal through the bile. Thus, the research suggests that eating lots of iron, fiber, and especially thiamine-rich foods “may induce rapid removal and excretion of…lead from the tissues.” But thiamine’s never been put to the test, where you give people thiamine, and see if their lead levels drop. The closest I could find is a thiamine intervention for lead-intoxicated goats.
And, much of the fiber data are just from test tube studies like this, where, under simulated intestinal conditions, complete with flasks of feces, both soluble and insoluble dietary fiber were able to bind up large amounts of mercury, cadmium, and lead to such an extent that they may have blocked absorption in the small intestine—though when our good gut flora then might eat the fiber, some of the heavy metals may be re-released in the colon. So, it’s not completely fail-safe, and, like thiamine, there haven’t been controlled human studies.
But look, where is thiamine found? Here’s some of the healthiest sources that also contain fiber, concentrated in super-healthy foods like beans and greens that we should all be eating anyway. So, even if thiamine and fiber-rich foods don’t actually lower your lead levels, you’d still end up healthier.
Iron was put to the test, though, and it failed to improve the “cognitive performance” of lead-exposed children, failed to improve “behavior” or ADHD symptoms. No surprise, because it failed to bring down lead levels, as did zinc supplementation. Turns out that while “iron may limit [the] absorption of lead,…it may also inhibit [the] excretion of…lead” that’s already in your body.
And, iron may not even inhibit lead absorption in the first place. That was based on rodent studies, and it turns out we’re not rodents.
Same story with zinc. It may have helped to protect rat testicles, but didn’t seem to help human children. “Nevertheless, iron is routinely prescribed in children with lead poisoning.” But, “[G]iven the lack of scientific evidence supporting the use of [indiscriminate] iron [supplementation] in… children with lead poisoning, its routine use should be reexamined.” Though obviously, if you have an iron deficiency, supplementation may help.
High fat intake has also been identified as something that make things worse for lead-exposed children. Dietary fat was associated with higher lead levels in a cross-sectional, snapshot-in-time study, and there is a plausible biological mechanism. Dietary fat may boost lead absorption by stimulating extra bile, which, in turn, may “contribute…to lead absorption.” But, you really don’t know until you put it to the test.
In addition to testing iron, they also tested fat. They gave a group of intrepid volunteers a cocktail of radioactive lead. Then, with a Geiger counter, they could measure how much radiation they retained in their bodies. Drinking the lead with iron or zinc didn’t change anything, but adding about two teaspoons of vegetable oil boosted lead absorption into the body from about 60% up to around 75%.
The only thing that seemed to help, dropping lead absorption down to about 40%, was eating a light meal with the lead drink. What was the meal? Coffee and a doughnut. I think this is the first doughnut intervention I’ve ever seen with a positive outcome. Could it have been the coffee? Unlikely, as, if anything, coffee drinking has been associated with a tiny increase in blood levels.
If fat makes things worse, and the one sugar they tried didn’t help, they figured that it was just “eating food”—any food—not taking in lead on an empty stomach, that made the difference. And, indeed, if you repeat the study with a whole meal, lead absorption doesn’t just drop from 60% to 40%, but all the way down to just 4%! That’s extraordinary. That means it’s 15 times worse to ingest lead on an empty stomach.
Please consider volunteering to help out on the site.
- Campbell C, Osterhoudt KC. Prevention of childhood lead poisoning. Curr Opin Pediatr. 2000 Oct;12(5):428-37.
- Mahaffey KR. Nutrition and lead: strategies for public health. Environ Health Perspect. 1995 Sep;103 Suppl 6:191-6.
- James HM, Hilburn ME, Blair JA. Effects of meals and meal times on uptake of lead from the gastrointestinal tract in humans. Hum Toxicol. 1985 Jul;4(4):401-7.
- Rosado JL, López P, Kordas K, García-Vargas G, Ronquillo D, Alatorre J, Stoltzfus RJ. Iron and/or zinc supplementation did not reduce blood lead concentrations in children in a randomized, placebo-controlled trial. J Nutr. 2006 Sep;136(9):2378-83.
- Kordas K, Stoltzfus RJ, López P, Rico JA, Rosado JL. Iron and zinc supplementation does not improve parent or teacher ratings of behavior in first grade Mexican children exposed to lead. J Pediatr. 2005 Nov;147(5):632-9.
- Batra N, Nehru B, Bansal MP. The effect of zinc supplementation on the effects of lead on the rat testis. Reprod Toxicol. 1998 Sep-Oct;12(5):535-40.
- Flanagan PR, Chamberlain MJ, Valberg LS. The relationship between iron and lead absorption in humans. Am J Clin Nutr. 1982 Nov;36(5):823-9.
- Wright RO. The role of iron therapy in childhood plumbism. Curr Opin Pediatr. 1999 Jun;11(3):255-8.
- Lucas SR, Sexton M, Langenberg P. Relationship between blood lead and nutritional factors in preschool children: a cross-sectional study. Pediatrics. 1996 Jan;97(1):74-8.
- Ou S, Gao K, Li Y. An in vitro study of wheat bran binding capacity for Hg, Cd, and Pb. J Agric Food Chem. 1999 Nov;47(11):4714-7.
- Taylor CM, Golding J, Hibbeln J, Emond AM. Environmental factors predicting blood lead levels in pregnant women in the UK: the ALSPAC study. PLoS One. 2013 Sep 5;8(9):e72371.
- Lee MG, Chun OK, Song WO. Determinants of the blood lead level of US women of reproductive age. J Am Coll Nutr. 2005 Feb;24(1):1-9.
- Ito Y, Niiya Y, Otani M, Sarai S, Shima S. Effect of food intake on blood lead concentration in workers occupationally exposed to lead. Toxicol Lett. 1987 Jul;37(2):105-14.
- Rico JA, Kordas K, López P, Rosado JL, Vargas GG, Ronquillo D, Stoltzfus RJ. Efficacy of iron and/or zinc supplementation on cognitive performance of lead-exposed Mexican schoolchildren: a randomized, placebo-controlled trial. Pediatrics. 2006 Mar;117(3):e518-27.
Icons created by Anand Prahlad, Jon Trillana and Imogen Oh from the Noun Project.
Image credit: Kristina DeMuth. Image has been modified.
Motion graphics by Avocado Video.
Republishing "How to Lower Lead Levels with Diet: Thiamine, Fiber, Iron, Fat, Fasting?"
You may republish this material online or in print under our Creative Commons licence. You must attribute the article to NutritionFacts.org with a link back to our website in your republication.
If any changes are made to the original text or video, you must indicate, reasonably, what has changed about the article or video.
You may not use our material for commercial purposes.
You may not apply legal terms or technological measures that restrict others from doing anything permitted here.
If you have any questions, please Contact Us
How to Lower Lead Levels with Diet: Thiamine, Fiber, Iron, Fat, Fasting?
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
This is why it’s critical to “get the lead out” of our tap water, but it’s estimated that most of our lead exposure comes from food, rather than water. It’s not what we eat, however, but what we absorb. If 90 percent of the lead in food is blocked from absorption by the very fact that it’s in food, you could get 10 to 20 times more lead absorbed into your bloodstream consuming the same amount of lead in water you drink on an empty stomach.
Where does all this lead exposure come from anyway? Check out the first five videos in this series:
- How the Lead Paint Industry Got Away with It
- Lead in Drinking Water
- How the Leaded Gas Industry Got Away with It
- “Normal” Blood Lead Levels Can Be Toxic
- The Effects of Low-Level Lead Exposure in Adults
For more on blocking lead absorption, as well as what to eat to help rid yourself of lead you’ve already built up, see:
- How to Lower Lead Levels with Diet: Breakfast, Whole Grains, Milk, Tofu?
- Best Foods for Lead Poisoning: Chlorella, Cilantro, Tomatoes, Moringa?
- Best Food for Lead Poisoning: Garlic
- Can Vitamin C Help with Lead Poisoning?
- Yellow Bell Peppers for Male Infertility and Lead Poisoning?
- How to Lower Heavy Metal Levels with Diet
Or, even better, don’t get exposed in the first place. Find out more in these videos:
- Get the Lead Out
- Lead Contamination of Tea
- Lead Contamination in Bone Broth
- Filled Full of Lead
- California Children Are Contaminated
Some of my other videos on lead include:
- Can Saunas Detoxify Lead from the Body?
- How to Lower Heavy Metals Levels with Diet
- How Much Lead Is in Organic Chicken Soup (Bone Broth)?
- Lead in Calcium Supplements
- Lead Contamination in Hot Sauces
And what about lead levels in women? See:
- The Rise in Blood Lead Levels at Pregnancy and Menopause
- Should Pregnant Women Take Calcium Supplements to Lower Lead Levels
- Is Lipstick Safe Given the Lead Contamination?
If you haven’t yet, you can subscribe to my videos for free by clicking here. Read our important information about translations here.