Case Study: Iron Deficiency Anemia in a 23-Year-Old Female
Chief Complaints:
Fatigue, headaches, nausea, irregular cycles, and cold hands and feet
Background
A 23-year-old female presented with chronic fatigue, intermittent headaches, nausea, and temperature intolerance, describing her hands and feet as “always cold.” She also noted irregular menstrual cycles (ranging from 24 to 45 days), though her bleeding pattern was otherwise normal in flow and duration.
Her diet consisted primarily of plant-based foods, with limited intake of animal protein. She reported a “mostly vegetarian” pattern, often skipping meals due to nausea. Upon further questioning, she disclosed frequent use of an over-the-counter proton pump inhibitor (PPI) for occasional heartburn.
Functional Medicine Workup
We conducted a comprehensive evaluation, including:
- Intake form and diet tracking using Cronometer app
- Comprehensive Stool Analysis (GI Effects)
- Serum Hormone & Nutrient Panel: Iron studies, CBC, CMP, B12, Folate, Vitamin D, zinc, copper, etc.
- Occult Blood Testing (to rule out gastrointestinal bleeding)
- Referral for Vaginal ultrasound (to rule out fibroids or other causes of menstrual irregularity)
Key Laboratory Findings
| Marker | Result | Reference Range | Comment |
| Hemoglobin | 11.2 g/dL | 12.0 – 15.5 | Low |
| Hematocrit | 33.5% | 36 – 46 | Low |
| MCV | 78 fL | 80 – 100 | Low (microcytic) |
| MCH | 25 pg | 27 – 33 | Low |
| RDW | 16.2% | 11.5 – 14.5 | High |
| Serum Iron | 32 µg/dL | 60 – 170 | Low |
| Ferritin | 9 ng/mL | 15 – 150 | Low |
| Transferrin Saturation | 9% | 25 – 35% | Low |
| Total Iron Binding Capacity (TIBC) | 435 µg/dL | 250 – 400 | High |
| Soluble Transferrin Receptor | Elevated | — | Consistent with iron deficiency |
| B12 | 412 pg/mL | 200 – 900 | Normal |
| Folate | 13 ng/mL | >3 | Normal |
| Vitamin D | 38 ng/mL | 30 – 100 | Adequate |
| Zinc | 69 µg/dL | 70 – 120 | Low-normal |
| Copper | 98 µg/dL | 80 – 155 | Normal |
Occult blood testing x 3 via LabCorp: Negative across multiple samples
Stool test: Normal pancreatic elastase, no blood, WBC or inflammatory patterns suggestive of IBD (normal calprotectin, eosinophil protein X and fecal secretory IgA). Insufficiency dysbiosis and low SCFA levels (butyrate specifically) and a few potential pathogens (Candida, Klebsiella)
Ultrasound: Referral made, waiting on results
Clinical Interpretation
Markers of iron deficiency anemia
Low/normal B12 (functional goal > 800) and Vitamin D levels (functional goal 50-70)
Low zinc levels (functional goal 100)
This patient’s presentation reflects classic iron deficiency anemia most likely due to decreased intake and absorption, not blood loss.
Her diet provided minimal iron sources, and her chronic PPI use likely compounded absorption issues by reducing stomach acid required to convert ferric to ferrous iron. Functional testing confirmed depleted iron stores (ferritin <10 ng/mL), low serum iron, and compensatory elevation in TIBC and RDW, consistent with stage 2–3 iron deficiency anemia.
Functional Medicine Treatment Approach
1. Address Underlying Causes
- Discontinued over-the-counter PPI and supported gastric function using digestive bitters and HCl supplementation (titrated as tolerated).
- Emphasized the role of adequate stomach acid for iron absorption.
2. Diet Optimization
- Encouraged prebiotic foods to support insufficiency dysbiosis and butyrate production. Also added Prebiotic Powder from Hyperbiotics, start low and increase slowly to 1 scoopy 5 days per week.
- Introduced heme iron–rich foods: grass-fed beef, chicken liver pâté, oysters, and clams (if tolerated).
- Encouraged combining plant-based sources (spinach, lentils, pumpkin seeds) with vitamin C–rich foods such as bell peppers, citrus, or kiwi to enhance absorption.
- Recommended limiting coffee, tea, and dairy around iron-rich meals.
3. Targeted Supplementation
- Started Proferin Clear (heme iron polypeptide) 1 capsule daily with meals, later titrated to 2 capsules, monitor for constipation
- Added Vitamin C 250 mg with iron to improve uptake.
- Avoided ferrous salts due to their lower bioavailability and GI side effects.
- Recommended zinc and copper repletion to maintain balance during long-term supplementation in the form of Zinc Balance, 1 capsule three times daily
- Introduced B12 lozenge from Designs for Health, Trifolamin once daily
4. Lifestyle and Cycle Regulation
- Addressed stress and circadian rhythm support to promote menstrual regularity.
- Planned hormone panel follow-up after iron repletion to evaluate potential secondary effects on cycle irregularity.
Follow-Up
After 8 weeks of dietary and supplement intervention, the patient reported:
- Noticeably improved energy and mood
- Resolution of headaches and nausea
- Slight improvement in menstrual cycles (average 30 days) although only had 2 cycles in this 8 week timeframe, continue to monitor
- Less temperature intolerance and better exercise tolerance
Repeat labs (8 weeks):
Ferritin increased to 28 ng/mL, Hemoglobin improved to 12.6 g/dL, and Transferrin Saturation normalized at 25%.
B12 normalized to 980 pg/mL
Zinc improved to 79 µg/dL
Key Takeaways
- Iron deficiency in young women often stems from low intake or impaired absorption, not necessarily blood loss but always very important to rule this out gastric bleed, IBD or menorrhagia .
- PPIs and low stomach acid are underrecognized contributors to deficiency.
- Functional evaluation should always include root-cause assessment—nutritional, hormonal, and gastrointestinal.
- Heme-based iron (like Proferin) and dietary correction are often better tolerated and more effective than standard ferrous salts.
- Addressing both diet and digestive function is crucial for sustained recovery.