Condition protocol · 6 min read

Telogen effluvium supplement protocol — iron, vitamin D, and what actually helps

Updated 2026-05-18 · Reviewed by SupplementScore editors · No sponsorships

Telogen effluvium (TE) is acute diffuse hair shedding triggered by a physiological stressor two to four months prior — an illness with high fever, childbirth, major surgery, severe weight loss, starting or stopping certain medications (oral contraceptive transitions, SSRIs, beta-blockers, retinoids, anticoagulants), or correctable nutritional deficiency. The hair-cycle reset itself is self-limiting in most cases — full recovery typically takes 6–12 months once the trigger has resolved. The supplement layer matters mainly through correctable deficiencies: ferritin, vitamin D, zinc, and thyroid status. Everything beyond those is supportive at best.

Read this first. Diffuse hair shedding has multiple causes — TE, female pattern hair loss (FPHL), thyroid disease, iron deficiency, drug-induced shedding, and others. Persistent shedding beyond 6 months, scarring patches, scalp inflammation, eyebrow or eyelash loss, or rapid progression deserves a dermatology evaluation. Hair loss work-up should include ferritin, full iron studies, TSH, free T4, vitamin D 25-OH, zinc, complete blood count, and (where indicated) ANA, syphilis serology, and hormones. Do not skip the labs — the deficiency-correctable cases respond well, and missing thyroid disease is a meaningful error.

What actually has trial evidence

Tier 1 evidence · Correctable deficiency

Iron — only when ferritin is low (test first)

Ferrous bisglycinate 25–50 mg elemental, on an empty stomach with vitamin C, every other day

Ferritin <30 ng/mL is associated with TE and other diffuse alopecias; the optimal hair-cycle ferritin target is debated, but most hair specialists aim for ferritin ≥50 ng/mL. Supplement only if ferritin is actually low — iron is hazardous in iron overload (hereditary hemochromatosis affects 1 in 200 people of Northern European ancestry). Bisglycinate is well-tolerated; alternate-day dosing improves absorption and reduces constipation. Take with vitamin C; separate from coffee, tea, calcium, and thyroid medication.

Tier 2 evidence · Correctable deficiency

Vitamin D3 — only when 25-OH-D is low (test first)

2,000–4,000 IU/day to a 25-OH-D target of 30–50 ng/mL

Vitamin D deficiency is more prevalent in TE and FPHL cohorts than in matched controls, and several small trials have shown improvement in shedding when deficiency is corrected. Test 25-OH-D and supplement to target; megadose annual bolus regimens are not appropriate.

Tier 2 evidence · Correctable deficiency

Zinc — only when serum zinc is low (test first)

Zinc bisglycinate or picolinate 15–22 mg elemental zinc/day with food

Frank zinc deficiency causes a characteristic alopecia and is overrepresented in some TE cohorts. Supplement only if documented deficiency. Long-term zinc supplementation without copper can produce copper deficiency — pair with 1–2 mg copper if zinc is continued more than 4–6 weeks.

Tier 2 evidence · Hair-cycle nutrition

Adequate protein intake (target 1.0–1.2 g/kg/day)

Diet first; whey or plant protein supplementation to gap-fill

Hair is largely keratin (a protein). Severe protein restriction and very-low-calorie dieting are well-documented TE triggers. Adequate protein intake is foundational. In users on calorie deficit (intentional weight loss, GLP-1 therapy), protect protein intake actively.

Tier 3 evidence · Adjunct (small RCT signal)

Marine collagen peptides (specific brands have trial evidence)

2.5–10 g/day specific marine collagen peptide preparations

Some small RCTs of specific marine collagen preparations show improved hair density and reduced shedding in women with self-reported thinning. Mechanism uncertain; effect likely modest. Generic collagen powder is unlikely to replicate trial-specific preparations' effects.

Tier 3 evidence · Hair-supplement formulation

Specific hair-supplement combinations (Nutrafol-style multivitamin + adaptogen blends)

Per product instructions

Several proprietary hair-supplement combinations (Nutrafol, Viviscal) have small RCT signal in women with self-reported thinning, but trials are funded by manufacturers and effect sizes are modest. Reasonable as an adjunct if budget allows and underlying deficiencies are already addressed; not appropriate as a first-line replacement for proper work-up.

What to address first — the underlying drivers

TE almost always has a trigger; identifying and addressing it matters more than any supplement:

What to skip

What to track

Repeat the "60-second hair count" weekly: count hairs lost in the morning shower or on the pillow. Photograph the part and crown in consistent lighting weekly. Track shedding count + scalp photos against the timeline. Most TE resolves 6–9 months after the trigger is removed and deficiencies are corrected. If shedding has not slowed at 6 months despite ferritin ≥50, 25-OH-D 30+, normal thyroid, and adequate nutrition, dermatology referral for biopsy or alternative diagnosis (FPHL, scarring alopecia) is reasonable.

Practical quick-start. Test first: ferritin, full iron studies, TSH, free T4, vitamin D 25-OH, zinc, CBC. Correct any deficiency: ferrous bisglycinate 25 mg elemental every other day on empty stomach (only if ferritin <50 ng/mL); vitamin D3 2,000–4,000 IU/day to target; zinc bisglycinate 15 mg/day with food (only if low). Protect protein intake (target 1.0–1.2 g/kg/day). Identify and address the upstream trigger (illness, postpartum, restrictive diet, medication change). Stop biotin if taking it. Expect 6–9 months for shedding to slow once the trigger is removed and deficiencies are corrected.