16/06/2026
Five nutrients. Chronically undertested in women. Here's what they are and what goes wrong when they're low.
1. Iron (ferritin — not just hemoglobin)
Your stored iron can be critically depleted while your hemoglobin reads normal. Low ferritin causes fatigue that doesn't respond to sleep, hair shedding, brain fog, and bone-deep exhaustion. that often gets blamed on stress, burnout, or just being female.
2. Magnesium
Over 300 enzymatic reactions depend on magnesium — including those that regulate cortisol, sleep quality, muscle tension, and blood sugar. Many women aren’t getting enough – and when the stress burden is high, sufficient magnesium becomes even more important. The form of magnesium you take is important, as is the form you test (ask for serum magnesium).
3. Vitamin D
It's technically a hormone precursor, not just a vitamin. A level of 30 is "normal" by lab standards, but research suggests women may function best between 60 and 80. That gap matters for mood, immunity, bone density, and thyroid health.
4. B12
Essential for nerve function, energy metabolism, and red blood cell production. If you've been eating mostly plants for any length of time and no one has talked to you about B12 monitoring — that's a clinical conversation worth having. Deficiency symptoms can include fatigue, mood changes, peripheral numbness, and cognitive changes – and once you’re deficient, recovery isn’t always quick.
5. Omega-3 fatty acids
In addition to being critical for cell membrane integrity, omega-3s are anti-inflammatory and considered cardio-protective, because they help maintain healthy cholesterol and triglyceride levels. Panels to assess omega-3 levels are available, but are not often offered.
None of this is a green light to Amazon-cart your way through a supplement stack. These nutrients show up in food first – that’s always the foundation. But if you’re still struggling, targeted testing tells you what you're actually dealing with before you start throwing capsules at it. Optimal ranges, forms, and context all matter, and that's where a clinician who actually looks at the full picture comes in.
If you've been feeling off and none of these have been evaluated — you have a starting point now. Bring these to your next appointment.
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