Researchers from the University of Edinburgh in Scotland and the Max Planck Institute for Biology of Ageing in Germany looked at three different aspects of biological aging and the genes associated with them:
lifespan (total years lived)healthspan (years lived without disease)longevity (survival until an exceptional old age)
Their research, published in a July 16 report in Nature Communications, found that the genes involved in metabolizing iron in the blood are connected to longer, healthier lives.
In addition, abnormally high or low levels of blood iron can lead to age-related health conditions, like liver disease, Parkinson’s disease, and a decreased ability to fight off infection.
“It appears that humans become less effective at incorporating iron into red blood cells as we get older,” Kalea Wattles, ND, a naturopathic physician and clinical content coordinator at the Institute for Functional Medicine, tells Verywell.
Wattles says that, as a result, more iron is left behind to create something called free radicals.
“Iron can participate in reactions that create ‘free radicals,’ which are compounds that are known to damage DNA and accelerate cellular aging,” she says. “In animal studies, this damage has been associated with signs of aging such as muscle wasting, brain tissue injury, and shortened lifespan.”
While Wattles says research regarding iron and free radicals in humans has largely only happened over the last decade, it shows free radicals can damage tissues throughout the body. Iron accumulation in the brain, for example, can contribute to conditions like Parkinson’s and Alzheimer’s disease.
The Risks of Too Much Iron
The Nature Communications study findings shed light on how high blood iron levels can reduce healthspan—or your healthy years of life.
“While iron is an essential mineral, it is potentially toxic at high levels," Wattle says. “In the setting of iron overload, iron is deposited into body tissues including the heart, liver, pancreas and joints. This can lead to heart failure, liver disease, elevated blood glucose, and arthritis. Recent evidence points to an association between elevated iron and shorter lifespans for humans as well.”
Sofia Norton, RD, a registered dietitian at Kiss My Keto, tells Verywell that iron overload from food or supplements can also cause immediate side effects, like constipation, nausea, vomiting, and stomach pain.
“Secondary iron overload from excessive intake will cause iron to accumulate in the body, which can damage organs,” she says, adding that this is rare in healthy people who are getting iron from their diet alone. She cautions that supplements are a different story, though, and should only be taken by people with diagnosed iron deficiencies.
The Risks of Too Little Iron
On the other hand, Norton says low iron levels can negatively affect muscle strength, energy levels, and mental abilities.
“Low iron levels exacerbate and increase the risk of age-related diseases because iron is essential for normal health,” she says. “For example, your body needs iron to make red blood cells that transport oxygen and to make enzymes involved in electron transfer and oxidation-reductions.”
How Much Iron Do You Need?
While this answer can be highly individualized depending on your health and the presence of any medical conditions, the National Institutes of Health offers some general guidelines.
Men (ages 19 and older): 8 milligramsWomen ages 19-50: 18 milligramsWomen ages 51 and older: 8 milligramsPregnant women: 27 milligrams
According to Norton, most people can get all the iron they need from a well-balanced, varied diet.
“To optimize your iron intake, eat a diet balanced in foods rich in both heme and non-heme iron,” she says. “Heme iron is found abundantly in animal protein food like red meat, poultry, eggs, and fish. Non-heme iron is found in plant foods, with richest sources being lentils, chickpeas, tofu, quinoa, dried apricots, and leafy greens.”
Wattle adds that not all sources of iron are created equal.
“It’s important to note that animal sources of iron and plant sources of iron are absorbed differently,” she says. Because of this, she says anyone following a vegan or vegetarian diet may have iron requirements one to two times higher than individuals who eat animal proteins.
