Optimal Ferritin: Evidence Backed Range for Ferritin

Contrary to popular belief, ferritin isn’t just about iron storage— it’s also a crucial marker of inflammation. In fact, iron is so vital that the body has no active way to excrete excess amounts, relying on absorption instead. Conventional reference ranges are skewed by widespread iron deficiency and inflammation, underestimating the risks of both low and high ferritin levels. As a result, early indicators of cardiovascular, cognitive, and metabolic health are overlooked.

At Superpower, we base our recommendations on the latest scientific research to define the optimal ferritin range. Our evidence-driven approach emphasizes proactive health management, addressing suboptimal ferritin levels early to prevent them from developing into more serious health concerns.

Key Points

• Ferritin's Dual Role: Ferritin is an iron storage protein, but also an important marker of inflammation.
• "Normal" is too HIGH: Conventional ranges underestimate health risks associated with both low and high ferritin.
• Conventional is NOT Optimal: Research shows that a narrower range correlates with better heart and brain health as well as improved profiles of inflammation
  • Conventional Range - Women: 10–307 ng/mL & Men: 20–336 ng/mL
  • Optimal Range. - Women: 45–80 ng/mL & Men: 60–120 ng/mL

What is the Role of Iron?

Iron is an essential mineral used to generate the protein hemoglobin. Your red blood cells use hemoglobin to deliver oxygen from the lungs and carry it throughout the body. Iron is also used to build myoglobin, a protein which provides oxygen to muscles. Unbound or free iron can catalyse oxidative stress and DNA damage through the so-called Fenton reaction causing cellular damage. The bad news is that we cannot measure free iron in tissues or inside cells, where it is likely causing the problem. However, blood markers of iron stores are useful predictors.

What is Ferritin?

Ferritin is a protein complex that stores iron in a safe, soluble, and non-toxic form, helping regulate iron levels and prevent damage from free iron ^[1]. By safely sequestering iron, ferritin protects cells from oxidative stress, which can occur when free iron reacts with oxygen, generating harmful free radicals.

Ferritin is made up of two types of subunits: heavy (H) chains, which handle the rapid oxidation of iron, and light (L) chains, which manage long-term iron storage ^[2]. This combination ensures that iron is readily available when needed for essential functions like oxygen transport, energy production, and cell growth.

Each ferritin molecule can hold up to 4,500 iron atoms, making it an efficient iron storage system ^[2]. When the body requires iron, ferritin releases it in a controlled manner.

Beyond iron storage, ferritin is critical in maintaining cellular functional and responding to inflammation. As an acute-phase reactant, ferritin levels rise significantly in response to inflammation, infection, or tissue damage, making it a sensitive marker for both iron metabolism and systemic inflammation ^{[3, 4]}. This is especially evident in chronic conditions such as autoimmune diseases, infections, or cancer, where ferritin production increases to sequester iron and protect against further damage.

Ferritin is primarily stored in organs like the liver, spleen, and bone marrow, but smaller amounts circulate in the bloodstream, allowing it to serve as a key biomarker for assessing overall iron stores.

Why Should You Care About Ferritin?

Ferritin is more than just an indicator of iron storage— its levels are strongly linked to heart health, brain function, metabolic syndrome, and inflammation ^[3-7].

Low ferritin levels often indicate iron deficiency, which can lead to fatigue, poor endurance, reduced cognitive performance, and weakened immune function. This is especially concerning for athletes, as iron deficiency can impair physical performance and slow recovery while sufficient ferritin levels improves performance and endurance ^{[8 - 10]}

Elevated ferritin levels often indicate inflammation in the body, as ferritin functions as an acute-phase reactant ^{[3, 4]}. During inflammatory processes, the body increases ferritin production to sequester iron, making it less available to pathogens. Ferritin levels often rise alongside other markers of inflammation like C-reactive protein and erythrocyte sedimentation rate, even in cases of low-grade inflammation ^{[4, 11, 12]}.

Elevated ferritin levels are also associated with metabolic syndrome, a group of conditions that increase the risk of heart disease, stroke, and type 2 diabetes ^[7]. High levels of iron and ferritin are linked to a higher prevalence of metabolic syndrome and insulin resistance ^{[7, 13]}. Excess ferritin can contribute to the development of glucose intolerance, type 2 diabetes, and disrupted sugar metabolism, including insulin resistance ^{[14, 15]}. The accumulation of iron in tissues, particularly in the liver and pancreas, leads to oxidative stress and inflammation, which impairs insulin sensitivity and disrupts normal sugar metabolism.

Ferritin levels is also an independent risk factor for heart problems ^{[5, 16]}. High ferritin, particularly in men, has been associated with an increased risk of cardiovascular disease ^[16]. Elevated ferritin could serve as a source of reactive iron and excess accumulation can promote oxidative stress, damaging blood vessels and increasing the risk of atherosclerosis and heart disease ^{[17 - 19]}.

Ferritin also plays a crucial role in brain health ^[6]. Iron is essential for producing neurotransmitters, delivering oxygen to the brain, and supporting energy metabolism. However, research suggests that excessively high ferritin levels are inversely associated with verbal memory and cognitive function ^[20]. This link highlights ferritin's potential role in brain aging and neurodegenerative diseases. Ensuring ferritin stays within an optimal range may protect cognitive function, particularly in aging populations ^[6].

Finally, ferritin levels correlate with death from all causes ^{[5, 21, 22]}. Both extremes of ferritin levels indicate underlying issues, with elevated levels signaling inflammation—a key driver of age-related diseases such as cardiovascular disease, diabetes, and cancer. Low ferritin, on the other hand, reflects iron deficiency, which can impair overall health.

Conventional Reference Range for Ferritin

The traditional reference range is oftentimes different for men and women with menstruating women having lower “normal” levels.  Typical levels are in the range:

• Women: 10–307 ng/mL
• Men: 20–336 ng/mL

Conventional ranges for ferritin are aimed at identifying extremes—severe iron deficiency on the low end and iron overload or inflammation on the high end—but they don’t always reflect what is healthiest for long-term health.

Superpower Optimal Range for Ferritin

At Superpower, we propose a more narrow optimal range of:

• Women: 45 – 80 ng/mL
• Men: 60 – 120 ng/mL

Ferritin levels at either extreme are linked to reduced performance and poor health outcomes. Our ranges are informed by research that shows that optimal levels, especially for heart and brain health, are narrower and lower than typical population-based ranges.

Health Note: Most absorbed iron is exported by intestinal cells and packaged into the transport protein transferrin. Tissues needing iron, like bone marrow (for red blood cell production), or the liver (for iron sensing and storage), take it up via transferrin receptors. While less responsive to short-term changes in iron metabolism, monitoring total iron levels, transferrin saturation, and hemoglobin is crucial for a comprehensive understanding of your iron status and overall metabolism.

Why Is The Conventional Range For Ferritin Problematic?

Anemia affects nearly one-fourth of the global population, and the body has no active mechanism for excreting excess iron. Iron follows a U-shaped dose-response curve, where both deficiency and excess pose significant health risks ^{[26, 27]}.

However, conventional ferritin reference ranges are based on population averages skewed by widespread anemia, poor iron absorption, and the body's inability to eliminate excess iron ^{[28 - 32]}. This results in broad and imprecise ranges that fail to identify optimal iron levels, overlooking both iron deficiency and overload.

Iron absorption from the diet is inefficient, especially for non-heme iron (from plant sources). Only a small fraction of dietary iron is absorbed, and factors like phytates (in grains), polyphenols (in tea and coffee), and calcium inhibit absorption ^{[33, 34]}.

The lower end of the conventional ferritin range is around 15 ng/mL, but research suggests that iron deficiency can occur at levels below 30 ng/mL, especially in women of reproductive age ^[24]. This means some individuals may be overlooked because their ferritin levels fall within the "normal" range.

Ferritin also acts as an acute-phase reactant, meaning its levels rise in response to inflammation or cell damage. This can lead to misdiagnosis, as iron-deficient individuals may show "normal" or elevated ferritin levels in the presence of inflammatory conditions such as infections, diabetes, or obesity ^{[11, 35]}.

High ferritin levels, often considered “normal,” have been linked to a reduced lifespan, particularly in older adults and men without chronic diseases ^[25]. Studies show that individuals with ferritin levels above 400 ng/mL had significantly shorter median survival compared to those with levels below 200 ng/mL, with risk falling further around 120 ng/mL ^{[36, 37]}. Increasing ferritin concentrations have also been correlated with a higher risk of premature death and death from all causes ^{[5, 22, 37]}. Severely elevated ferritin levels are an independent predictor of in-hospital death, increasing the risk by 119% ^[21].

Even moderately elevated ferritin is associated with metabolic syndrome and insulin resistance ^{[7, 38 - 40]}. Excess iron causes oxidative damage to pancreatic cells, and high-normal ferritin levels have been linked to an increased risk of diabetes and impaired sugar metabolism ^{[23, 41]}.

Supporting Evidence from Research Studies

Despite its critical role, iron's U-shaped dose-response curve has a very narrower optimal range ^{[26, 27]}. Recent studies indicate that maintaining ferritin within ~20 - 130 ng/mL provides significant benefits for longevity, physical performance, and cognitive function.

Ferritin levels within the high-normal range, have been linked to shortened lifespan. Men with ferritin levels above 190 ng/mL face a significantly increased risk of death from heart disease and other causes compared to those with levels between 70 - 120 ng/mL ^[5]. Similarly, genetically predicted higher iron levels are associated with reduced life expectancy, reinforcing the need for stricter control of iron stores ^{[42 - 45]}.

In a study of 1,300 older men with normal iron levels, reducing ferritin from 120 to 80 ng/mL through bloodletting was associated with a 37% reduction in cancer risk, and cancer survival rates were doubled [46]. Moreover, high ferritin levels are associated with shorter telomere length - a marker of cellular aging, and ferritin production is increased in response to pro-longevity factors, suggesting that optimal ferritin levels can help slow down biological aging ^{[47 - 50]}.

Ferritin levels also display a U-shaped relationship with cognitive health and performance ^{[51 - 54]}. Elevated levels (>200 ng/mL in women, >300 ng/mL in men) are associated with worse cognitive task performance, while low ferritin (<30 ng/mL) also impairs cognitive function, though to a lesser extent ^{[55 - 57]}. Elevated ferritin levels have been shown to predict the progression from mild cognitive impairment to Alzheimer's disease, particularly when ferritin remains chronically high ^[57].

Ferritin levels above ~250 ng/mL are linked to decreased bone health ^{[58 - 61]}. Ferritin levels above 120 ng/mL are associated with elevated markers of inflammation like C-reactive protein and increased oxidative stress ^[5]. In combination, this can harm bone-forming cells and increase bone breakdown. Conversely, low ferritin levels, below 15–20 ng/mL, may impair collagen synthesis and bone formation ^[60]. Even mild-to-moderate iron deficiency is associated with significant bone health deterioration ^[61].

In athletes, low ferritin levels (<20 ng/mL) are linked to fatigue and reduced performance, but maintaining levels just above this threshold, ~30 ng/mL, improves endurance and reduces your risk of injury ^{[10, 24]}

Emerging Research: Popular longevity interventions like rapamycin, calorie restriction, and dilution of old plasma possibly exert their beneficial effects by modulating iron metabolism ^[62]!

The Key Takeaway

Ferritin is not just a marker of iron storage; it's also a key indicator of inflammation. Conventional ranges often fail to reflect optimal health, as they are skewed by widespread iron deficiency and elevated inflammatory states. As a result, what’s considered "normal" may overlook the risks of both iron overload and deficiency. These extremes can lead to serious health issues like cardiovascular disease, metabolic dysfunction, and cognitive decline in both men and women.

At Superpower, our approach is rooted in emerging research that identifies a narrower, more precise ferritin range. Studies show that ferritin levels of 45 – 80 ng/mL in women and 60 –120 ng/mL in men are associated with better heart and brain health, reduced inflammation, and improved longevity. We’re not just aiming to prevent deficiency or iron overload—we're focused on optimizing ferritin levels for long-term health and well-being.