• Log in with Facebook Log in with Twitter Log In with Google      Sign In    
  • Create Account
  LongeCity
              Advocacy & Research for Unlimited Lifespans

Photo
- - - - -

Iron intake and cancer risk

meat intake cancer iron hemochromatosis

  • Please log in to reply
4 replies to this topic

#1 Skötkonung

  • Guest
  • 1,556 posts
  • 33
  • Location:Västergötland, SE

Posted 07 September 2011 - 12:21 AM


One of the reasons that red meat intake could be associated with higher levels or mortality (and cancer) could because of the heme iron content (via oxidative damage)? That's unfortunate for me.. I have hemochromatosis and my transferrin saturation is almost constantly elevated (85% or higher) even if my ferritin levels are within a healthful range. I've already had problems with a adrenal adenoma, although I cannot say for certain it is linked to iron intake.

A little background reading:
When measuring the body's potential to store iron, transferrin saturation is a common laboratory test. It is usually calculated as a percentage and is the ratio of serum iron and total iron-binding capacity, multiplied by 100. Of the transferrin that is available to bind iron, this value tells a clinician how much serum iron is actually bound. For instance, a value of 15 % means that 15 % of free iron is being carried by transferrin.

Some relevant research:
Moderate elevation of body iron level and increased risk of cancer occurrence and death
"Men and women were divided into 5 groups on the basis of baseline transferrin saturation: 0 to 30%, 30–40%, 40–50%, 50–60%, and 60% and higher. Nineteen percent of men had a baseline transferrin saturation above 40% (the last 3 groups), whereas only 10 percent of women had transferrin saturation above 40%. For men and women combined, risk of cancer occurrence in each group relative to the first was 1.0, 0.95, 1.16, 1.38 and 1.81; for mortality the relative risks were 1.0, 0.96, 1.22, 1.29 and 1.73. There is evidence, in this cohort, of elevated cancer risk in those with moderately elevated iron level. This pattern was seen in women as well as in men."

Transferrin Saturation and Risk of Cancer
"In women, a positive association was observed between transferrin saturation and risk of stomach carcinoma (≥34.5% compared with ≤20.3%: relative risk (RR) = 3.5, 95% confidence interval (Cl) 0.98–12). In men, transferrin saturation was inversely associated with risk of colon and rectal carcinoma (≥40.7% compared with ≤26.0%: colon, RR = 0.62, 95% Cl 0.35–1.1; rectum, RR = 0.30, 95% Cl 0.08–1.1) and with non-Hodgkin's lymphoma (32.1–40.6% compared with ≤26.0%: RR = 0.31, 95% Cl 0.11–0.88; no cases observed with transferrin saturation ≥40.7%)."

The Mortality Risk of Elevated Serum Transferrin Saturation and Consumption of Dietary Iron
"Ingestion of large quantities of dietary iron and red meat in persons with high transferrin saturation is associated with an increase in mortality. Simple dietary restrictions may reduce the mortality risk associated with high transferrin saturation."

Transferrin Saturation in vegetarians versus omnivores:
The impact of vegetarianism on some haematological parameters
"Vitamin B12 and iron status were compromised by a vegetarian diet. Variations in mean corpuscular volume were determined by iron and vitamin B12 status. Lower lymphocyte and platelet count were accompanied by metabolic evidence that indicated vitamin B12 deficiency." Specifically, this study found lower transferrin saturation (almost pathologically low) in vegetarians.

Iron status of predominantly lacto-ovo vegetarian East Indian immigrants to Canada: a model approach
"Iron deficiency was higher among females than males: 33% vs 5%, respectively, via the TI model (serum ferritin, serum-transferrin saturation, and mean corpuscular- hemoglobin concentration) and 18-42% vs 2-22%, respectively, via individual biochemical-iron indices."

The bottom line:
You may not have hemochromatosis, but significant meat intake will raise transferrin saturation and predispose you to higher rates of cancer. High levels of alcohol intake and high levels of vitamin C intake will increase iron absorption regardless of whether the source is animal or plant. Tannins and phytates will block iron availability. Taking supplemental inositol-hexaphosphate with iron rich meals may be beneficial to those chronically high transferrin saturation.
  • like x 2

#2 lucid

  • Guest
  • 1,195 posts
  • 65
  • Location:Austin, Tx

Posted 11 September 2011 - 11:51 PM

Thanks for the links / summary:

I don't have hemochromatosis but have been donating blood 4x/ year because of the following studies:

IRON AND THE SEX DIFFERENCE IN HEART DISEASE RISK

Premenopausal women in affluent societies are protected from heart diseases which kill large numbers of men. The basis for this sex difference and the loss of protection with menopause is unknown. The hypothesis offered is that the greater incidence of heart diseases in men and postmenopausal women compared with the incidence in premenopausal women is due to higher levels of stored iron in these two groups. The hypothesis is supported by observations of (1) myocardial failure in iron storage diseases, (2) accumulation of stored iron with age in men, and (3) accumulation of stored iron after menopause to levels found in men. In addition, the heart diseases of affluence are rare among impoverished peoples who are often iron deficient. The depletion of iron stores by regular phlebotomy could be the experimental system for testing this hypothesis, and a preventive therapy if the hypothesis is confirmed.

http://www.sciencedirect.com/science/article/pii/S0140673681924636

Donation of Blood Is Associated with Reduced Risk of Myocardial Infarction

Because high body iron stores have been suggested as a risk factor for acute myocardial infarction, donation of blood could theoretically reduce the risk by lowering body iron stores. For this reason, the authors tested the hypothesis that voluntary blood donation is associated with reduced risk of acute myocardial infarction in a prospective epidemiologic follow-up study in men from eastern Finland. The subjects are all participants of the Kuopio Ischaemic Heart Disease Risk Factor Study. A cohort of 2, 862 men aged 42–60 years were followed for an average of almost 9 years. One man (0.7%) out of 153 men who had donated blood in 24 months preceding the baseline examination experienced an acute myocardial infarction during 1984 to 1995, whereas 316 men (12.5%) of 2, 529 non-blood donors had an acute myocardial infarction (p < 0.0001 for difference between proportions). In a Cox proportional hazards model adjusting for age, examination years and all other predictive coronary disease risk factors, blood donors had a 88% reduced risk (relative hazard = 0.12, 95% confidence interval 0.02–0.86, p = 0.035) of acute myocardial infarction, compared with non-blood donors. These findings suggest that frequent blood loss through voluntary blood donations may be associated with a reduced risk of acute myocardial infarction in middle-aged men. Am J Epidemiol 1998; 148: 445–51.

http://aje.oxfordjournals.org/content/148/5/445.short

I think there was another study in kentucky that found <40% reduced risk. I also ran into one study just a minute ago negating the above conclusion. I'll have to look into it more.

sponsored ad

  • Advert
Click HERE to rent this advertising spot for NUTRITION to support LongeCity (this will replace the google ad above).

#3 hggh

  • Guest
  • 15 posts
  • 13
  • Location:California

Posted 21 September 2011 - 09:20 AM

Would be good to drink a green tea (or garlic, fiber, calcium, magnesium, vitamin E [organic, hulled sunflower seeds are rich in fiber, vitamin E, and magnesium], or red wine) to reduce iron levels in food.

Or eat a polyphenol rich food (I try to take a POMx pill supplement when I eat red meat, or at least normal tea drink which has polyphenol). Here is a UC Berkeley video lecture on iron (mentions polyphenol, and importance of iron for oxygen delivery too).

Edited by hggh, 21 September 2011 - 09:39 AM.


#4 TheFountain

  • Guest
  • 5,362 posts
  • 257

Posted 29 September 2011 - 03:26 PM

Although vegetarian diets are associated with reduced iron volume most people would be surprised at how much iron a vegetarian can intake over the course of one day, in some cases in the range of 140% RDA but still have low iron volume.

I think the bioavailability of meat derived iron vs vegetarian derived iron sources has a great deal to do with it. heme iron (from meat soruces) is absorbed along with the iron already bound by hemoglobin but isn't co-dependent on this and will be absorbed at any rate, whereas nonheme iron (non-meat sources) absorption is dependent on the iron already in your blood. Vegetarians without high iron stores already could see difficulty in absorbing dietary iron.

I wonder if the blood iron volume of vegetarians isn't actually a happy medium when it comes to low risk factor for certain conditions associated with high iron intake vs deficiency. Not stating anything definitive here, just guessing.

Edited by TheFountain, 29 September 2011 - 03:30 PM.


#5 GhostBuster

  • Guest
  • 107 posts
  • 22

Posted 30 September 2011 - 02:44 PM

What if Tullio Simoncini is right and cancer is caused by fungi?

Fungi and other parasites need iron and they have a capacity to get it:

Iron uptake in fungi: A system for every source

http://www.sciencedirect.com/science/article/pii/S0167488906001091

Hemoglobin Predicts Quality of Life in Cancer Patiens

http://www.medscape.com/viewarticle/440702

Iron status markers in patients with small cell carcinoma of the lung. Relation to survival

http://www.ncbi.nlm....les/PMC1977453/

Edited by GhostBuster, 30 September 2011 - 03:09 PM.






Also tagged with one or more of these keywords: meat intake, cancer, iron, hemochromatosis

2 user(s) are reading this topic

0 members, 2 guests, 0 anonymous users