Vegan Runner With Amenorrhea and Low Ferritin
Your client is a 27-year-old female recreational runner who follows a vegan diet and is training for a half marathon. She is 55 kg, 168 cm, and reports 5 months of amenorrhea, fatigue, and hair loss. Labs: ferritin 12 ng/mL, hemoglobin 11.8 g/dL, vitamin B12 180 pg/mL. She takes omeprazole daily for GERD. A 3-day food recall shows about 1,400 kcal/day, 35 g protein/day, no fortified plant milks or B12-fortified foods, and coffee with every meal. She eats lentils and spinach most days but takes them with coffee and without vitamin C. Her training volume increased from 25 to 55 km/week over 6 weeks. She has no history of disordered eating, but she often feels too busy to eat lunch. She asks you to 'fix my hormones' with a supplement and whether she should stop omeprazole.
1. Interpret the assessment data. What nutrition and medical issues should be explored, and which require referral?
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Several findings point in the same direction. Her energy intake (about 1,400 kcal) and protein (35 g, about 0.6 g/kg) are low for half-marathon training, and her volume rose quickly from 25 to 55 km/week. That combination raises concern for low energy availability. Ferritin 12 ng/mL is low, hemoglobin 11.8 g/dL is borderline, and B12 180 pg/mL is low-normal; omeprazole can reduce B12 and iron absorption, and coffee with meals further impairs nonheme iron uptake.
Amenorrhea for 5 months is not a nutrition problem to 'fix' with a supplement-it requires medical evaluation, especially with fatigue and hair loss. I would refer to her physician for the amenorrhea and labs and to a registered dietitian for individualized care. I would not diagnose RED-S or iron deficiency anemia myself, but I would describe the concerns and support the referral. Bone health and thyroid or other causes should be on the physician's radar.
2. Identify three specific nutrition changes with mechanisms that could improve iron and B12 status and support training.
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1. Pair plant iron with vitamin C and move coffee: add citrus, bell pepper, or tomato to lentils and spinach, and separate coffee or tea by at least 1 hour from iron-rich meals. Vitamin C improves nonheme iron absorption, while coffee tannins inhibit it.
2. Increase total energy and distribute protein: move toward about 1.2–1.4 g/kg/day (roughly 66–77 g) with 20–30 g at meals, using tofu, tempeh, lentils, beans, and fortified plant milk. This supports training and recovery and helps correct low energy availability.
3. Secure B12: use B12-fortified plant milk or nutritional yeast daily, or a supplement after physician or pharmacist review. With omeprazole, absorption may be reduced, so the dose and form need medical guidance. I would also discuss iron supplement use only with the physician, because ferritin 12 with borderline hemoglobin needs evaluation, not self-dosing.
3. She asks you to recommend a 'hormone reset' supplement and to stop omeprazole. How do you respond within scope?
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I would be direct: those are outside my scope. A 'hormone reset' supplement cannot be recommended without knowing the cause of her amenorrhea, and with her low energy availability, fatigue, and low ferritin, a stimulant or herbal product could do harm. Stopping omeprazole is a medication change that belongs to her prescriber, especially because she has GERD and the PPI affects B12 and iron.
I would explain the risk, not just refuse: unregulated supplements can contain unknown ingredients, and the priority is medical evaluation plus adequate energy, iron-rich food pairing, and B12. I would offer to prepare a food and symptom summary for her physician and dietitian, document the request and my response, and continue coaching only on food and behavior. If she wants supplement guidance, I would route it to the prescriber or pharmacist.