Iron Bisglycinate
Plant-based diets often run low on bioavailable iron.
- Typical dose
- 18 mg
- When to take
- Afternoon
- Onset
- Ferritin rises over 2–3 months; energy improvements often noticed within 2–4 weeks
What it does
Benefits
- Corrects iron-deficiency anemia
- Restores energy in deficient individuals
- Supports oxygen transport and cognitive function
- Bisglycinate form is gentler on the gut than ferrous sulfate
The science
How it works
Iron is central to hemoglobin, which carries oxygen in red blood cells. Deficiency impairs oxygen delivery — fatigue, poor exercise tolerance, brain fog.
Getting it right
Dose & timing
Dose guidance
18 mg bisglycinate daily for maintenance. Treating deficiency: 30–60 mg elemental iron under medical guidance, with ferritin monitoring. Don't supplement without confirmed deficiency.
Best time to take
Between meals with vitamin C for best absorption. Avoid coffee, tea, calcium, and dairy within 2 hours — all block absorption.
Is it for you?
Who should (and shouldn't) take it
Good for
- Menstruating women (especially heavy periods)
- Vegans and vegetarians (plant iron is less bioavailable)
- Endurance athletes
- Pregnancy (under medical guidance)
Skip or ask a doctor if
- You haven't confirmed deficiency with a ferritin test
- You have hemochromatosis
- You're a man with normal iron (men rarely need to supplement)
Know before you start
Side effects & safety
- Constipation (less common with bisglycinate)
- Nausea
- Dark stools (harmless)
- Iron overload with unnecessary supplementation — serious
Shopping guide
Forms & what to look for
- Bisglycinate
Gentlest; well-absorbed
- Ferrous sulfate
Cheap, effective, more GI side effects
- Ferrous gluconate
Middle ground
- Heme iron
From animal sources; highest bioavailability
Combining
Stacks well with / avoid pairing
Stacks well with
Avoid pairing with
Common questions
FAQ
Should I just take iron to feel more energetic?
No — get a ferritin test first. Iron overload causes real harm. Supplement only if deficient.
Every day or every other day?
Recent research suggests alternate-day dosing increases absorption and reduces side effects.
Can I take it with my multi?
Check — if your multi already has iron, don't double up without a reason.
References
Sources & further reading
Educational only, not medical advice. Check with a clinician before starting anything new, especially if you're on medication or pregnant.
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