Iron Bisglycinate vs Quercetin

Mineral vs Immune · evidence-backed comparison

Quick take
  • Iron Bisglycinate has the stronger evidence base (strong (multiple rcts / meta-analyses)).
  • Iron Bisglycinate has the broader effect profile across the 9 effect categories.
  • Iron Bisglycinate is cheaper per serving ($0.18 vs $0.35).
  • Quercetin has a slightly cleaner safety profile.
  • Iron Bisglycinate has higher bioavailability (better absorption).

Side-by-side traits

TraitIron BisglycinateQuercetin
Category
MineralImmune
Active compound
Ferrous bisglycinateQuercetin
Form available
Capsule, TabletCapsule, Tablet
Source
syntheticplant
Typical dose
18–25 mg elemental iron500–1000 mg daily
Dose range
18–25 mg500–1000 mg
Loading protocol
Best taken with
vitamin C, empty stomach (or with food if GI sensitive)vitamin C (potentiates)
Best time of day
morningany
Bioavailability
How efficiently the body absorbs and utilizes the compound.
Very High (5/5)Low (2/5)
Onset time
Cumulative: 4–12 weeksCumulative: 2–6 weeks
Half-life
~17 hours
Evidence level
Quality and quantity of human research.
Strong (multiple RCTs / meta-analyses)Moderate (some RCTs)
Overall effect
Subjective effect magnitude.
Moderate (3/5)Low (2/5)
Muscle / strength
Low (2/5)Very Low (1/5)
Physical energy
High (4/5)Low (2/5)
Focus / cognition
Moderate (3/5)Very Low (1/5)
Mood / stress
Moderate (3/5)Very Low (1/5)
Sleep quality
Low (2/5)Very Low (1/5)
Immunity
Low (2/5)High (4/5)
Recovery
Post-exercise recovery support.
Moderate (3/5)Moderate (3/5)
Longevity / healthspan
Very Low (1/5)High (4/5)
Safety rating
5 = exceptionally well-tolerated; 1 = significant risk profile.
Moderate (3/5)High (4/5)
Price per serving
Approximate USD per typical daily dose.
$0.18$0.35
Vegan friendly
YesYes
Gluten free
YesYes
3rd-party tested
YesYes

About Iron Bisglycinate

Best-tolerated iron form for treating deficiency anemia. Don't supplement without a confirmed low ferritin / low Hgb test.

Active compound: Ferrous bisglycinate
Forms: Capsule, Tablet
Onset: Cumulative: 4–12 weeks
anemiaenergymenstruationendurance

About Quercetin

Polyphenol with antihistamine and senolytic properties. Common in protocols for allergies and viral infections; pair with vitamin C.

Active compound: Quercetin
Forms: Capsule, Tablet
Onset: Cumulative: 2–6 weeks
antihistaminesenolyticimmunepolyphenol

Iron Bisglycinate safety

Common side effects:

  • Constipation (less than ferrous sulfate)
  • Dark stools

Avoid if:

  • Hemochromatosis
  • Iron overload
  • Untested males without deficiency

Drug interactions:

  • Levothyroxine
  • Calcium
  • PPIs

Quercetin safety

Common side effects:

  • Headache
  • Tingling extremities (high doses)

Avoid if:

  • Kidney disease

Drug interactions:

  • Cyclosporine
  • Quinolone antibiotics
  • Anticoagulants

Common uses

  • Anemia treatment
  • Heavy menstruation
  • Endurance athletes

Stacks well with: Vitamin C

Common uses

  • Seasonal allergies
  • Immune support
  • Senescent cell clearance

Stacks well with: Vitamin C, Zinc

Medical disclaimer

SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements — especially if you are pregnant, breastfeeding, take prescription medication, or have a chronic condition.