After analyzing genetic data, a team of researchers from Imperial College London and University College London have found that iron 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.
The team then focused on these SNPs in a group of more than 50,000 patients with CAD, finding that those with the SNPs for higher iron status also had a lower risk of CAD.
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.
Factors such as age and gender can affect results and make it difficult to assess how iron levels influence the risk of CVD.
“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, “Just as when someone’s cholesterol levels are high we give them a statin, it could well be the case that if their iron levels are low, we could give them an iron tablet to minimize their risk of cardiovascular disease. 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.”
According to the World Health Organization, CVD is the leading cause of death worldwide, causing more than seven million deaths a year.
A lack of iron can also lead to anemia, tiredness, shortness of breath, heart palpitations and increase the risk of infection.
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.
The findings can be found published online in the journal Arteriosclerosis, Thrombosis, and Vascular Biology.