A new study has found a link between low levels of iron and a higher risk of heart disease. After analysing genetic data, a team of researchers from Imperial College London and University College London have found that iron-rich foods could have a protective effect against coronary artery disease (CAD), a type of cardiovascular disease (CVD) where clogged arteries reduce the amount of blood reaching the heart.
The team looked at the impact of genetic variants on people’s iron status by gathering genomic data from 48,000 people in a public database. They focused on three points in the genome where a single ‘letter’ difference in the DNA — called a single nucleotide polymorphism (SNP) — can slightly increase or reduce a person’s iron status, which is the amount of the nutrient in the body.
Although previous research has already shown that iron status plays a role in CVD risk, the results have been conflicting, with some studies finding that high iron status has a protective effect, while others have suggested that high iron status could actually increase the risk of heart attacks.
“As our genes are randomly allocated before we are born, their impact on our systemic iron status is less affected by the lifestyle or environmental factors that can confound observational studies,” explained Dr Dipender Gill, lead author of the study. However, the researchers also pointed out that the findings now need to be validated in a randomized controlled trial to see if iron supplements have any impact on the risk of CVD.
“Our findings have potential implications for public health,” Dr Gill added, “For those people who have already had a heart attack, and whose iron status is low, we could potentially reduce their risk of having another heart attack just by giving them an iron tablet. This is an exciting idea that warrants further investigation.”
Men require less than nine milligrams of dietary iron per day, however women under 50 need closer to 15 milligrams, although most people are able to get enough iron from their diet, with iron found in foods such as red meat, pork and poultry, seafood, beans, dark green leafy vegetables, such as spinach, and dried fruit, such as raisins and apricots.