Your Lab Says Normal. Your Hair May Disagree.

I have been saying this for years: a reference range can miss iron deficiency. The 2026 ASH guideline has now moved the official diagnostic line closer to where many clinicians already suspected it belonged. But there is a second confusion that the new guideline does not solve, and it is the one I see most often in patients asking about hair shedding or laser recovery. A diagnostic cutoff answers whether you are deficient. It does not answer whether your biology is ready for what a treatment is about to ask of it.

Normal · Deficient · Ready

What is a normal ferritin level, and why can “normal” still be low?

A “normal” ferritin on your lab report only means the result falls inside that laboratory’s population reference interval. That is a different question from whether iron deficiency is likely, and different again from whether your body is ready for a specific demand. Three separate lines answer three separate questions, and most confusion about ferritin comes from treating them as one.

• A laboratory range asks whether your result falls inside that lab’s population interval.
• A diagnostic guideline asks whether iron deficiency is likely.
• A procedure-planning target asks whether your biology appears ready for a specific demand, such as growing hair or healing after resurfacing.

The diagnosis line: ASH now suggests ≤30 ng/mL

The 2026 American Society of Hematology guideline suggests a ferritin of 30 ng/mL or below, rather than the older 15 ng/mL, to diagnose iron deficiency in adults, including menstruating and pregnant people. That applies irrespective of whether hemoglobin is normal. The recommendation is conditional and based on low-certainty evidence, which is worth knowing, but it is a meaningful shift: many results that were previously reported as unremarkable now fall on the deficient side of the line.

Keep the distinction clear. This is a diagnosis line. It is not a universal hair-growth target, and it is not a procedure-readiness target.

When symptoms or ongoing losses move the line to ≤50 ng/mL

ASH notes that a threshold of 50 ng/mL or below can be appropriate when adults have symptoms of iron deficiency or continuing risk factors. The same higher threshold can be appropriate with heavy menstrual bleeding, abnormal uterine bleeding, upcoming surgery, or pregnancy planning.

Inflammation changes interpretation. Ferritin rises during inflammation, so for anemia of inflammation ASH recommends ferritin together with fasting transferrin saturation (TSAT), not ferritin alone.

My selected-patient planning target: 70+ ng/mL

For selected hair-loss and elective procedure patients, I often want ferritin of at least 70 ng/mL before asking the body to build hair, recover from fractional CO2, or respond to a biostimulatory plan. That is provided the value, TSAT, CBC, symptoms, losses and inflammatory context make that target safe and appropriate for the individual.

Why I sometimes say “not yet”

Can low ferritin cause hair loss?

Low ferritin is associated with some forms of nonscarring hair loss, especially diffuse shedding, but it is rarely the whole story. Studies use different ferritin cutoffs, the exact “optimal” level for hair remains debated, and hair loss can also reflect genetics, thyroid disease, hormones, medications, illness, stress, inflammation, scarring conditions or other nutritional factors.

Hair growth is an expensive biological project, and hair can be the first place a reserve problem becomes visible. A 2022 systematic review and meta-analysis in women linked iron deficiency with nonscarring alopecia, and earlier work in the Journal of the American Academy of Dermatology examined iron status in female pattern hair loss and chronic telogen effluvium against controls. The point is not to treat one number. In my clinic a shedding assessment combines:

• the shedding pattern and a scalp examination;
• a CBC, ferritin and iron studies, including transferrin saturation;
• thyroid function;
• nutrition and protein intake;
• medications and relevant hormone history.

Evidence boundary: human association evidence exists; the exact optimal ferritin target for hair remains debated.

Does iron matter for CO2 laser recovery?

Iron sufficiency is biologically relevant to healing after fractional CO2, but no controlled human trial proves that a ferritin of 70 is a universal CO2 threshold. A resurfacing treatment creates a controlled repair demand: the skin has to re-epithelialize, remodel the extracellular matrix and rebuild collagen. Iron supports oxygen transport, mitochondrial energy, DNA synthesis and iron-dependent enzymes involved in that repair, which is why a 2014 review in Frontiers in Pharmacology examined iron’s role in skin and wound healing.

The treatment can be ready before your biology is. If oxygen delivery, iron handling, protein, thyroid function or inflammation is off, adding a device does not solve the foundation. That is why iron status sits beside the other readiness checks in my CO2 laser planning and in the pre-care steps of the CO2 laser recovery guide. For the wider picture of what recovery demands from skin, see why skin sometimes gets worse when you are doing everything right.

Evidence boundary: mechanistic and general wound-healing rationale; no direct ferritin-70 CO2 trial.

Biostimulators: collagen stimulation is a biological process

Biostimulatory injectables are not an instant fill. They depend on your own inflammatory, fibroblast and matrix-remodeling response. I do not want to ask a depleted system for an ambitious response without first understanding anemia, iron stores, protein intake, inflammation and other recovery constraints. This is clinical reasoning, not a proven guarantee of a better injectable result; direct outcome trials by ferritin level are lacking.

Taking iron is not the same as absorbing iron

How do you raise ferritin with food?

Food helps most when you pay attention to the iron source, what you pair it with, and what you keep away from it. Heme iron from animal foods is generally absorbed more efficiently than non-heme iron from plants. Vitamin C can improve non-heme absorption within a meal, while coffee and tea can reduce it. Source, pairing, timing, ongoing losses and inflammation all change the result.

Should you take vitamin C with every iron tablet?

Not automatically. Vitamin C helps non-heme iron from food, but a randomized clinical trial in JAMA Network Open found oral iron alone was equivalent to oral iron plus vitamin C for iron-deficiency anemia. The right regimen depends on the product, your diet, tolerance and your clinician’s plan.

The supporting cast

• Lactoferrin. Trials and reviews suggest possible improvements in ferritin or hemoglobin with better gastrointestinal tolerance in some populations, but products, doses and study groups vary. It is not a substitute for diagnosing blood loss.
• Vitamin A and copper. Both participate in normal iron mobilization and red-cell biology. I correct a documented deficiency; I do not recommend blind high-dose supplementation.
• B12 and folate. They do not directly increase iron absorption. They matter because deficiencies can impair normal red-cell production and create a second reason the CBC is not recovering.
• Dose and schedule. More is not always better. Depending on the patient, a lower or alternate-day oral schedule may improve absorption and tolerance, as a 2020 Haematologica study in iron-deficient women suggested. Intravenous iron is reserved for specific clinical situations. The dose and schedule are decisions to make with your physician.

When ferritin will not move

Why is my ferritin still low after taking iron supplements?

When ferritin stays low despite supplements, the answer is usually not more iron. It is finding out why your body is losing it, not absorbing it, not mobilizing it, or not responding the way the original plan predicted. Ferritin is one part of an iron assessment; the CBC, transferrin saturation, symptoms, losses, inflammation and timing of the test can all change interpretation.

1. You are still losing iron. Heavy menstrual bleeding, frequent blood donation, gastrointestinal bleeding, surgery, pregnancy and endurance-related losses can outrun replacement. Treating the source matters as much as replacing the iron.
2. Your gut cannot absorb it well. Celiac disease, H. pylori infection, autoimmune or atrophic gastritis, inflammatory bowel disease, bariatric surgery and chronic acid-suppressing medication can reduce absorption. SIBO belongs on the differential when the symptoms and history fit, but it is not the first explanation for everyone.
3. Inflammation is hiding the deficit. Ferritin is an acute-phase reactant. It can rise during inflammation even when usable iron is restricted. That is why ASH recommends evaluating ferritin with fasting transferrin saturation in anemia of inflammation and interpreting both in the full clinical context. If inflammation is part of your picture, this guide to inflammatory testing explains what we measure.
4. The plan is not reaching the target. Dose, formulation, timing, side effects, adherence, a competing B12 or folate deficiency, kidney disease or an incorrect diagnosis can all make ferritin appear “stubborn.” Re-testing should answer why, not trigger endless supplement escalation.

Early randomized pilot, not proof

Can a salmon protein supplement raise ferritin? What the ProGo pilot showed

A small 2026 pilot found that a salmon protein hydrolysate called ProGo nudged ferritin, hemoglobin and red-cell count upward compared with whey, which is interesting because the product contains almost no iron. It is an early signal, not a treatment for iron deficiency or hair loss.

In the double-blind trial, published in Biomedicines, seven adults received 12 g a day of ProGo and seven received matched whey protein for 56 days. Ferritin, hemoglobin, red-blood-cell count and a self-reported hair, nail and skin composite favored ProGo. The study was not a treatment trial in iron-deficient or hair-loss patients.

Why it is worth studying

• Randomized, double-blind, active-controlled design.
• The primary hematology endpoints remained significant after correction for multiple comparisons.
• ProGo contained only 3.1 mg of iron per kg, less than the whey comparator.
• The signal may involve iron-handling biology rather than direct iron replacement, but the mechanism was not measured in this trial.

Why it is still early

• Only 14 participants, seven per arm, with no formal power calculation.
• Participants were not required to have iron deficiency, anemia, hair loss or skin disease.
• Hair, nail and skin outcomes were subjective self-ratings, not objective hair counts or dermatologic measurements.
• Several authors were employees or consultants of Hofseth BioCare, and the statistician collaborated with the company.

Critical context: mean baseline ferritin was already 183.3 ± 85.2 µg/L in the ProGo arm and 174.0 ± 85.4 µg/L in the whey arm. This was not a study of depleted iron stores. Finished consumer beverages that use salmon peptides, such as STNDRD, have not been shown publicly to be identical to the powdered ProGo intervention, and they are not iron replacement or a treatment for hair loss. The ASH guideline defines iron deficiency; the pilot explores a salmon-protein hydrolysate. Neither paper proves that every patient needs ferritin of 70 before a procedure. I cover the same pilot from the weight-loss angle in ProGo, protein and GLP-1 care.

Measure before you push harder

What should a ferritin and hair-loss workup include?

A useful review connects your symptoms with the treatment you are asking your body to recover from. Depending on the question, that means your menstrual or bleeding history, diet, medications and gut history, alongside a CBC, ferritin, fasting TSAT, inflammatory markers, thyroid function, B12 and folate, and copper or vitamin A when indicated. The common reasons patients come to us:

All of these sit inside the physician-directed panels on our precision diagnostics page.

Frequently asked questions

Does ferritin below 30 mean iron deficiency even if hemoglobin is normal?

The 2026 ASH guideline suggests ferritin at or below 30 ng/mL for diagnosing iron deficiency in most adults, irrespective of whether anemia is present. Symptoms, ongoing losses, pregnancy, inflammation and transferrin saturation can change interpretation.

Does ASH recommend ferritin above 70 for hair growth or CO2 laser?

No. ASH addresses the diagnosis of iron deficiency; it does not set a ferritin-70 hair, CO2 laser or biostimulator target. Ferritin of at least 70 ng/mL is Dr. Sajic’s clinic-specific optimization target for selected patients, not a universal guideline.

Can low ferritin cause hair loss?

Low ferritin is associated with some forms of diffuse nonscarring hair loss, but study thresholds and results vary. Hair loss can also reflect genetics, thyroid disease, hormones, medications, illness, stress, inflammation, scarring disease or nutritional factors. A scalp and medical assessment matter.

Should I take vitamin C with every iron tablet?

Vitamin C can improve non-heme iron absorption from food, but a randomized clinical trial found oral iron alone equivalent to oral iron plus vitamin C for iron-deficiency anemia. The best regimen depends on the product, diet, tolerance and your clinician’s plan.

Why can ferritin stay low despite supplements?

Continuing menstrual or gastrointestinal blood loss, poor adherence or tolerance, celiac disease, H. pylori, atrophic gastritis, inflammatory bowel disease, bariatric surgery, acid-suppressing drugs, inflammation or a competing diagnosis can all contribute. The response should be investigated rather than treated with endless dose escalation.

Does ProGo replace iron treatment?

No. The ProGo pilot enrolled only 14 people who were not required to be iron deficient, found early hematologic signals, and needs confirmation. It should not replace diagnostic work, prescribed oral or intravenous iron, or evaluation for blood loss and malabsorption.

Is a high ferritin a good thing?

Not necessarily. A high ferritin can signal inflammation, liver disease, infection, metabolic disease or iron overload. Too much iron can be harmful, so supplements and intravenous iron need a diagnosis, a dose and follow-up.

Verifiable sources

The ASH recommendation is conditional and based on low-certainty evidence. The hair-loss data are associations with varying cutoffs. The CO2 and biostimulator reasoning is mechanistic, not trial-proven. The ProGo trial is a 14-person, company-connected pilot in people without iron deficiency.

• Powers JM, et al. American Society of Hematology 2026 guidelines for diagnosis of iron deficiency. Blood Advances. 2026. doi:10.1182/bloodadvances.2025015950
• Auerbach M, DeLoughery TG, Tirnauer JS. Iron deficiency in adults: a review. JAMA. 2025;333:1813–1823.
• Pasricha SR, Tye-Din J, Muckenthaler MU, Swinkels DW. Iron deficiency. The Lancet. 2021;397:233–248. doi
• Treister-Goltzman Y, Yarza S, Peleg R. Iron deficiency and nonscarring alopecia in women: systematic review and meta-analysis. Skin Appendage Disorders. 2022;8:83–92. PMC
• Olsen EA, et al. Iron deficiency in female pattern hair loss, chronic telogen effluvium, and control groups. Journal of the American Academy of Dermatology. 2010;63:991–999. PubMed
• Wright JA, Richards T, Srai SKS. The role of iron in the skin and cutaneous wound healing. Frontiers in Pharmacology. 2014;5:156. PMC
• Expert consensus on clinical recommendations for fractional ablative CO2 laser in facial skin rejuvenation treatment. Lasers in Medical Science. 2025. PMC
• Li N, et al. The efficacy and safety of vitamin C for iron supplementation in adult patients with iron deficiency anemia: a randomized clinical trial. JAMA Network Open. 2020;3:e2023644. doi
• Stoffel NU, et al. Iron absorption from supplements is greater with alternate-day than consecutive-day dosing in iron-deficient anemic women. Haematologica. 2020;105:1232–1239. PubMed
• National Institutes of Health Office of Dietary Supplements. Iron: fact sheet for health professionals. ods.od.nih.gov
• Snook J, et al. British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults. Gut. 2021;70:2030–2051. gut.bmj.com
• The effectiveness of oral bovine lactoferrin compared with iron supplementation in patients with a low hemoglobin profile: systematic review and meta-analysis. 2024. PMC
• Currie C, Myklebust TÅ, Bjerknes C, Framroze B. A pilot study of salmon protein hydrolysate (ProGo®) supplementation to assess its impact on hematologic, integumentary and metabolic health. Biomedicines. 2026;14:1663. doi