When it comes to iron supplementation, one of the most important questions is “What dose is right for me?” The answer depends on several factors, but ferritin levels are often a key starting point.

Ferritin is a storage protein that reflects how much iron your body has in reserve. It’s not the only marker involved in iron metabolism, but it’s one of the most commonly tested and clinically relevant tools for guiding supplementation decisions.

Why ferritin matters

While hemoglobin measures how much iron your red blood cells are using, ferritin measures how much iron is in storage, which is often where deficiency starts. Many people may have normal hemoglobin but low ferritin, especially women of childbearing age, vegetarians/vegans, endurance athletes, and individuals with digestive or absorption challenges.

Interpreting ferritin levels in context

Here’s a general breakdown of ferritin levels and what they might indicate in clinical practice:

These ranges can vary slightly by lab, region, and clinical setting, but they offer a helpful guide.

Matching FERAPRO^® strength to ferritin levels

FERAPRO^® offers three strengths: 30 mg, 75 mg, and 150 mg of elemental iron per capsule. Choosing the right one is about matching dose to need: not too much, not too little, and always balancing efficacy with tolerability.

Ferritin < 30 µg/L

Consider: FERAPRO^® 150

This is the most appropriate dose for those with clear iron deficiency or anemia. At this level, your body is likely in a deficit and needs aggressive repletion. If well tolerated, a daily dose of 150 mg elemental iron may be recommended for 3–6 months under practitioner guidance.

Exception: If you’ve had side effects on iron before, FERAPRO^® 75 is a better starting point with close monitoring.

Ferritin 30–50 µg/L

Consider: FERAPRO^® 75

This range indicates low iron stores, which can be enough to cause symptoms like fatigue, brain fog, or hair shedding, even if hemoglobin is still normal. A medium-strength dose helps rebuild reserves while being gentler on digestion. It can also be used in cases where higher doses are poorly tolerated.

Ferritin 50–75 µg/L

Consider: FERAPRO^® 30

This is a subclinical or borderline range, often seen in women who feel “okay” but not optimal. While not classically deficient, this range can be associated with mild fatigue or low resilience, particularly in menstruating women, plant-based eaters, and athletes. A gentle dose like 30 mg every other day can support replenishment before deficiency sets in.

Ferritin > 75 µg/L

Consider: Maintenance or pause

At this level, you may be replete or near repletion, especially if symptoms have improved. Depending on the context, such as post-pregnancy or after a repletion phase, FERAPRO^® 30 may be used every other day or a few times per week to maintain stores. Some women may choose to stop temporarily and monitor.

Always consider the full picture

Ferritin is just one piece of the puzzle. When selecting a dose, it’s also important to assess:

• Symptoms, such as fatigue, brain fog, low mood, or hair loss
• Dietary intake, especially because plant-based diets may reduce iron availability
• Menstrual blood loss
• Digestive health and absorption
• History of side effects on iron supplements
• Pregnancy or postpartum status

Practitioners often combine ferritin with other markers, such as hemoglobin, transferrin saturation, or serum iron, to form a more complete picture.

Summary: A tailored approach based on ferritin

FERAPRO^®’s three-tier dosing system offers the flexibility to adjust based on your lab work, how you feel, and how well you tolerate iron.