LEAD
Action News vol 10 no 2, June 2010, ISSN 1324-6011
Incorporating Lead Aware Times ( ISSN 1440-4966) and Lead Advisory Service
News (ISSN 1440-0561)
The Journal of The LEAD (Lead Education and Abatement Design) Group Inc.
Vitamin E
is an essential nutrient but supplementation is not recommended for
pregnant women (due to potential heart problems in the fetus) and
individuals at risk of stroke, on anti-coagulant medication or with
Vitamin K deficiency (due to anti-coagulant properties). There are 8 forms
of Vitamin E, and only one form, (alpha-tocopherol) is retained in
significant quantity within the body and is generally used in supplements
but supplementation with one form can reduce levels of the other forms
with unknown impacts.
In a similar manner to
vitamin C a number of studies have found Vitamin E to be inversely
associated with blood lead levels as well increasing the robustness of
lead-impacted red blood cells. In addition, a number of studies in rats
have found Vitamin C and E to be protective of lead-induced kidney, liver
and brain damage particularly in conjunction with each other, partially
because vitamin C can recycle Vitamin E into its active form. Vitamin C
operates within body fluids, including cellular fluids, destroying
oxidizing molecules, while vitamin E acts to protect structures such as
cell membranes. Some animal studies have indicated an impact on indicators
relating to hypertension, but impacts on hypertension have not been
confirmed by human studies.
Vitamin E: Tocopherol is
found predominantly with vegetable oils. The following contain
high levels: Back row: vegetable oils (wheat germ, sunflower,
safflower, palm, linseed, peanut, corn, olive [pictured]), curry
paste (or powder), marzipan, wheat germ. Front row: nuts(Almond,
hazel, pine), margarine. Not Pictured: fish liver and oils
(haddock, cod), fish roe
Vitamin E is found in
good quantities in a wide range of nuts, seeds and vegetable oils. There
is, however, some evidence that vitamin E supplementation can slightly
reduce the average lifespan, though it may reduce risks in some subgroups,
e.g. dialysis patients, some diabetic individuals, or smokers at least 66
years of age with high vitamin C levels. Consuming 814IU (560mg) of
vitamin E a day was recommended as safe by the UK government’s Expert
Group on Vitamins and Minerals, though considerable uncertainty exists on
long- term impacts.
Graded
Associations of Blood Lead and Urinary Cadmium Concentrations with
Oxidative-Stress–Related Markers in the U.S. Population: Results
from the Third National Health and Nutrition Examination Survey
Duk-Hee Lee, Ji-Sun Lim, Kyungeun Song, Yongchool Boo, and David R.
Jacobs Jr Environmental Health Perspectives VOLUME 114 | NUMBER 3 |
March 2006 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1392227/
[Finds that low vitamin E levels are associated with higher blood lead
levels. Figure one allows a comparison of the impact of vitamin C and
vitamin E levels on blood lead]
Antioxidant effects
of α tocopherol, ascorbic acid and l.-methionine on lead-induced
oxidative stress to the liver, kidney and brain in rats R. C. Patra,
D. Swarup and S. K. Dwivedi Toxicology Vol 162, No 2, 11 May 2001,
Pages 81-88 http://www.ncbi.nlm.nih.gov/pubmed/11337108
[Found that vitamin C, E
and methionine reduced damage to these three organs, but that vitamin
E had larger impacts on the brain and liver]
Effect of treating
lactating rats with lead acetate and its interaction with vitamin E or
C on neurobehavior, development and some biochemical parameters in
their pups A. A. Hassan and H. M. Jassim Iraqi Journal of Veterinary
Sciences, Vol. 24, No. 1, 2010 (45-52) http://www.vetmedmosul.org/ijvs/media/10-1-9e.pdf
[The conclusion has a good brief summary of the differing yet
interconnected impacts of vitamin C and E as antioxidants.]
Increased nitric
oxide inactivation by reactive oxygen species in lead-induced
hypertension Nosratola D Vaziri, Kaihui Liang and Yaoxian Ding Kidney
International (1999) 56, 1492-1498 http://www.nature.com/ki/journal/v56/n4/pdf/4491060a.pdf
[Demonstrates a role for
vitamin E in reducing lead-induced hypertension, at least in rats. But
see next entry]
Does Increased
Oxidative Stress Cause Hypertension? Ehud Grossman Diabetes Care 31 (Suppl.
2):S185–S189, 2008 http://care.diabetesjournals.org/content/31/Supplement_2/S185.full.pdf+html
[A critical appraisal of the use of antioxidants to treat
hypertension. Page S187 column 1 has a review of the disappointing
studies of vitamin C and E supplementation and hypertension.]
Decision Analysis
Supports the Paradigm That Indiscriminate Supplementation of Vitamin E
Does More Harm than Good Yedidya Dotan; Ilya Pinchuk; Dov Lichtenberg;
Moshe Leshno Arteriosclerosis, Thrombosis, and Vascular Biology.
2009;29:1304 http://atvb.ahajournals.org/content/29/9/1304.short
[An examination of a range of studies that finds individuals who take
supplemental vitamin E on average live 4 months less in life-quality
adjusted terms].
Vitamin E may
increase and decrease mortality Harri Hemilä letter and reply by
Lichtenberg American Heart Association at http://atvb.ahajournals.org/letters/#919
[Hemila quotes his own study of older smokers to show Vitamin E can be
beneficial. Lichtenberg makes the point that the article he co-wrote
(cited above) never disputed this, citing studies of renal and
diabetic patients.]