Iron Deficiency Problems: More Than Just Anemia

By Alchemist-hp (talk) (www.pse-mendelejew.de) - Own work, FAL, https://commons.wikimedia.org/w/index.php?curid=10115787

Iron deficiency can have harmful effects other than just anemia (which is bad enough); there can be problems with immune and nervous system function, as well as other negative effects.  Abstract:

OBJECTIVE:

To consider the key implications of iron deficiency for biochemical and physiological functions beyond erythropoiesis.

METHODS:

PubMed was searched for relevant journal articles published up to August 2017.

RESULTS:

Anemia is the most well-recognized consequence of persisting iron deficiency, but various other unfavorable consequences can develop either before or concurrently with anemia. Mitochondrial function can be profoundly disturbed since iron is a cofactor for heme-containing enzymes and non-heme iron-containing enzymes in the mitochondrial electron transport chain. Biosynthesis of heme and iron-sulfur clusters in the mitochondria is inhibited, disrupting synthesis of compounds such as hemoglobin, myoglobin, cytochromes and nitric oxide synthase. The physiological consequences include fatigue, lethargy and dyspnea; conversely iron repletion in iron-deficient individuals has been shown to improve exercise capacity. The myocardium, with its high energy demands, is particularly at risk from the effects of iron deficiency. Randomized trials have found striking improvements in disease severity in anemic but also non-anemic chronic heart failure patients with iron deficiency after iron therapy. In vitro and preclinical studies have demonstrated that iron is required by numerous enzymes involved in DNA replication and repair, and for normal cell cycle regulation. Iron is also critical for immune cell growth, proliferation and differentiation and for specific cell-mediated effector pathways. Observational studies have shown that iron-deficient individuals have defective immune function, particularly T-cell immunity, but more evidence is required. Preclinical models have demonstrated abnormal myelogenesis, brain cell metabolism, neurotransmission and hippocampal formation in iron-deficient neonates and young animals. In humans, iron deficiency anemia is associated with poorer cognitive and motor skills. However, the impact of iron deficiency without anemia is less clear.

CONCLUSION:

The widespread cellular and physiological effects of iron deficiency highlight the need for early detection and treatment of iron deficiency, both to ameliorate these non-erythropoietic effects and to avoid progression to iron deficiency anemia.

Rats and Colon Cancer

A study shows that dietary risk factors thought to contribute to colon cancer in humans induce early stage colonic lesions in rats.

Epidemiological studies have demonstrated clear associations between specific dietary and environmental risk factors and incidence of colorectal cancer, but the mechanisms responsible for these associations are not known. An animal model could facilitate such an understanding.

Both genotoxic and nongenotoxic carcinogens induce aberrant crypt foci (ACF) in the colons of F344 rats. F344 rats were provided with diets that contained putative risk factors for CRC: low calcium and low vitamin D, high iron, high fructose, and decreased light (UV) exposure or a control diet for 14 wk. The rats were then assessed with biochemical measures and by topological examination for evidence of colon abnormalities. Circulating ionized calcium was decreased from 2.85 to 1.69 mmol/L, and ACF were increased from 0.7 to 13.6 lesions/colon (both P < 0.001).

Rats exposed to the multiple environmental conditions associated with colon cancer, developed ACF similar to the heterogeneous or ill-defined ACF in the human colon. Heterogeneous ACF are the type most frequently seen in humans, and are also seen in rats shortly after exposure to the non-genotoxic colon carcinogen, dextran sulfate sodium. The rodent model could be used to assess the pathways from diet and environment to colon cancer and to provide guidance for clinical studies.

Consider carefully the results with "high fructose" - do we really need high fructose corn syrup in our diets? Also, the "high iron" is another warning shot about red meat.