Too much iron in red meat raises heart disease risk
According to a new study at Indiana University School of Public Health, the risk of heart disease may be increased by consuming iron found in red meat. But the researchers found that getting iron from other sources of food did not have the same negative effect.
The scientists focused on heme iron—the kind found in beef and other animal-based foods. One of the main differences between heme iron and non-heme iron--which is found in vegetables--is that heme iron is better absorbed by the body. That's why dieticians often recommend that people with iron deficiencies consume more meat.
The researchers collected data from 21 studies in order to examine the effects of heme, non-heme and total iron on people’s risk of coronary heart disease. The studies were conducted over 10 years and involved about 300,000 participants. The findings, which will appear in an upcoming issue of the Journal of Nutrition, showed that the participants who consumed the most heme iron from meat or fish raised their risk of developing heart disease by 57 percent, when compared with the participants who consumed the least amount of heme iron.
The results of the study may be explained at least in part by how iron absorption works. Researchers said that when the body absorbs heme iron, oxidation of low-density lipoprotein (LDL)—the “bad cholesterol”—is sped up, which can lead to tissue damage and inflammation. The researchers acknowledged that the study did not show that iron from animal-based foods caused heart disease.