People who regularly consume iron-rich foods may benefit from improved heart health, but they may also be unknowingly increasing their risk for stroke.
Researchers at Imperial College London examined the medical data of more than 500,000 people to find out how iron affects the development of over 900 different diseases in the body.
Health Effects Of High Levels Of Iron
They found that naturally high levels of iron can help lower people's risk of high cholesterol levels and even prevent the buildup of fatty substances in the arteries.
However, the team also found that high levels of the mineral can make people more susceptible to stroke due to increased risk of blood clots. It also makes the skin more vulnerable to different bacterial infections.
The results show the important role iron plays in maintaining good health as well as the dangers of having high levels of the mineral in the body.
"Iron is a crucial mineral in the body, and is essential for carrying oxygen around the body," said Dr. Dipender Gill, lead author of the study.
"However, getting the right amount of iron in the body is a fine balance — too little can lead to anaemia, but too much can lead to a range of problems including liver damage."
Identifying 'Iron' Genes
Using a technique called Mendelian Randomization, Gill and his colleagues looked at the potential link between iron levels and disease development. They sought out certain genetic "variants", known as single-nucleotide polymorphisms, which may help explain why some people have naturally higher levels of iron.
The researchers also examined the likelihood of patients with single-nucleotide polymorphisms to develop medical conditions and illnesses, such as atherosclerosis and high cholesterol levels.
Atherosclerosis occurs when calcium, fibrin, cholesterol, fatty substances, and cellular waste products accumulate in the arteries, according to the American Heart Association. The more these plaques build up in the arteries, the thicker the wall of the blood vessels become. This greatly reduces the flow of blood and lessens the amount of oxygen and other nutrients circulating throughout the body.
Patients suffering from atherosclerosis may go on to develop other serious diseases such as severe chest pain (angina), coronary heart disease, peripheral artery disease, and chronic kidney disease. The condition can also result in heart attack and stroke.
The study's findings reveal that naturally higher iron levels were indeed linked to lower atherosclerosis and high cholesterol risks.
Higher Risk Of Stroke And Skin Infections
Gill and his team also found that higher iron levels can increase the risk of clots related to slower blood flow. This can cause people to become more susceptible to stroke and deep vein thrombosis. The results also showed the potential of developing different skin infections associated with high iron levels.
While the results provide new insights regarding the role of iron on human health, they also raise many questions. Researchers have yet to understand how the mineral affects cholesterol levels, narrows the arteries, and causes blood to clot.
Gill theorizes that lower cholesterol levels may be associated with the reduced risk of some arteries becoming furred. Higher levels of iron may also cause more blood clots to form when the flow of blood is reduced. This may help explain why the researchers found an increased occurrence of blood clots in their study.
As for the increased risk of skin infections, Gill believes that iron may also play a crucial role in the replication and virulence of certain bacteria.
The findings of the Imperial College London study are featured in the Journal of the American Heart Association and PLOS Medicine.
