IU研究:红肉中的血红素铁摄入多了,患心脏病风险升高.

动物食物特别是红肉中的血红素铁易被身体吸收，和来自蔬菜的非血红素铁的吸收率相比为 37% ：5%，很多营养专家建议吃肉类以摄入铁。4月23日 Indiana University School of Public Health发表的文章里，对过去10年21项包括近30万人的研究进行分析，发现摄入血红素铁多的人，和很少摄入血红素铁的人相比，患心脏病风险升高57%。而摄入非血红素铁再多，也不会增加患心脏病风险。因为红肉中的血红素铁一旦被吸收，​​它可能成为在LDL(低密度脂蛋白)氧化过程中的催化剂，从而导致组织损伤的炎症，这是一个潜在的冠心病危险因素。

全文: http://www.sciencedaily.com/releases/2014/04/140423170903.htm
 

IU Health and Vitality: Iron and heart disease, animal memory, and yoga tips

Research and insights from Indiana University

• April 23, 2014

FOR IMMEDIATE RELEASE

The April issue of IU Health & Vitality discusses the following topics:

• Study: Iron consumption can increase risk for heart disease
• IU study opens prospects of new treatments for memory impairment
• Yoga is supposed to bring attention -- not tension -- to the body

Study: Iron consumption can increase risk for heart disease

Jacob Hunnicutt

A new study from the Indiana University School of Public Health-Bloomington has bolstered the link between red meat consumption and heart disease by finding a strong association between heme iron, found only in meat, and potentially deadly coronary heart disease.

The study found that heme iron consumption increased the risk for coronary heart disease by 57 percent, while no association was found between nonheme iron, which is in plant and other non-meat sources, and coronary heart disease.

The study was published online ahead of print in the Journal of Nutrition. Along with first author Jacob Hunnicutt, a graduate student in the school's Department of Epidemiology and Biostatistics, the study’s co-authors are Ka He and Pengcheng Xun, faculty members in the department.

Hunnicutt said the link between iron intake, body iron stores and coronary heart disease has been debated for decades by researchers, with epidemiological studies providing inconsistent findings. The new IU research, a meta-analysis, examined 21 previously published studies and data involving 292,454 participants during an average 10.2 years of follow-up.

The new study is unique because it looks at the associations of total iron consumption as well as heme and nonheme iron intake in comparison to the risk of coronary heart disease. The only positive association involved the intake of heme iron.

The body treats the two kinds of iron differently. It can better control absorption of iron from vegetable sources, including iron supplements, but not so with iron from meat sources.

"The observed positive association between heme iron and risk of CHD may be explained by the high bioavailability of heme iron and its role as the primary source of iron in iron-replete participants," the researchers wrote in the journal article. "Heme iron is absorbed at a much greater rate in comparison to nonheme iron (37 percent vs. 5 percent). Once absorbed, it may contribute as a catalyst in the oxidation of LDLs, causing tissue-damaging inflammation, which is a potential risk factor for CHD."

 

Iron stores in the body increase over time. The only way to reduce iron in the body is by bleeding, donating blood or menstruation. Some dietary choices, such as coffee and tea, also can inhibit iron absorption.

 

A demonstration of low impact "hatha" yoga