Research article

Nutrition to Fight Lead Poisoning

By Robert J. Taylor, additional references sourced by Elizabeth O’Brien, Edited by Anne Roberts,
Photos by Catherine Sweeny. A Fact Sheet version of this Research Article can be found at www.lead.org.au/fs/Fact_sheet-Nutrients_that_reduce_lead_poisoning_June_2010.pdf

Glutathione and cysteine Glutathione is a major antioxidant that undertakes key functions within the body, particularly in the brain and liver, where it plays a major role in detoxifying xenobiotics (foreign compounds) and carcinogens. The depletion of glutathione in these two organs is a major impact of lead toxicity, with glutathione deficiencies being linked to brain cell death. Glutathione is poorly absorbed, at least from supplements, but it is manufactured within the body, so the optimum way to maximize levels is through maintaining good levels of the precursor molecules: cysteine, glutamic acid (glutamate as a salt) and glycine. Cysteine is the rarest of these in western diets, and is found in red peppers, garlic, onions, broccoli, Brussels sprouts, oats and wheat germ. It is readily destroyed by heat and processing, so little survives in cooked eggs or pasteurized milk, though significant amounts are found in undenatured (processed at low temperature) whey protein; and whey has been consistently linked with higher glutathione levels. However, should cysteine be unavailable, new cystine (the stable form of cysteine) can be formed by breaking down methionine. Glutamate is more common and is found in food flavorings such as MSG and a variety of protein-rich foods, including meat, fish and beans. It can also be manufactured inside the liver from other amino acids.

Glutathione also requires vitamin B6 for its manufacture but, in a demonstration of the complexities involved, B6 deficiency can actually increase glutathione levels. Given that glutathione manufacture occurs and is regulated inside the body, it cannot be automatically assumed that consumption of glutathione precursors, or glutathione itself, will directly relate to glutathione levels within the body, though it may maximize possible production.

1. Glutathione Wikipedia http://en.wikipedia.org/wiki/Glutathione

2. The systemic availability of oral glutathione A. Witschi, S. Reddy, B. Stofer and B. H. Lauterburg European Journal of Clinical Pharmacology Vol 43 No 6 Dec 1992 www.springerlink.com/content/051307ur34175737/

3. Lead-Induced Cell Death Of Human Neuroblastoma Cells Involves GSH Deprivation Chellu S. Chetty, Mohan C. Vemuri, Khamisi Campbell And Challa Suresh Cellular & Molecular Biology Letters Volume 10, (2005) pp 413 – 423 www.cmbl.org.pl/pdf/Vol10_p413.pdf [Shows that glutathione depletion plays a significant role in neuron (brain cell) death.]