Iron Bisglycinate vs NAC (N-Acetyl Cysteine)

Mineral vs Immune · evidence-backed comparison

Quick take
  • NAC (N-Acetyl Cysteine) has the broader effect profile across the 9 effect categories.
  • Iron Bisglycinate is cheaper per serving ($0.18 vs $0.22).
  • NAC (N-Acetyl Cysteine) has a slightly cleaner safety profile.
  • Iron Bisglycinate has higher bioavailability (better absorption).

Side-by-side traits

TraitIron BisglycinateNAC (N-Acetyl Cysteine)
Category
MineralImmune
Active compound
Ferrous bisglycinateN-acetyl L-cysteine
Form available
Capsule, TabletCapsule, Powder
Source
syntheticsynthetic
Typical dose
18–25 mg elemental iron600–1800 mg daily
Dose range
18–25 mg600–1800 mg
Loading protocol
Best taken with
vitamin C, empty stomach (or with food if GI sensitive)empty stomach or with food
Best time of day
morningany
Bioavailability
How efficiently the body absorbs and utilizes the compound.
Very High (5/5)Moderate (3/5)
Onset time
Cumulative: 4–12 weeksAcute and cumulative
Half-life
~6 hours
Evidence level
Quality and quantity of human research.
Strong (multiple RCTs / meta-analyses)Strong (multiple RCTs / meta-analyses)
Overall effect
Subjective effect magnitude.
Moderate (3/5)Moderate (3/5)
Muscle / strength
Low (2/5)Low (2/5)
Physical energy
High (4/5)Low (2/5)
Focus / cognition
Moderate (3/5)Low (2/5)
Mood / stress
Moderate (3/5)Moderate (3/5)
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$0.22
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 NAC (N-Acetyl Cysteine)

Glutathione precursor used clinically for liver protection (acetaminophen overdose). Strong evidence for OCD, COPD, and PCOS.

Active compound: N-acetyl L-cysteine
Forms: Capsule, Powder
Onset: Acute and cumulative
glutathioneliverlungOCD

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

NAC (N-Acetyl Cysteine) safety

Common side effects:

  • Sulfur smell
  • GI upset
  • Headache

Avoid if:

  • Asthma (rare bronchospasm)

Drug interactions:

  • Nitroglycerin
  • Anticoagulants
  • Activated charcoal

Common uses

  • Anemia treatment
  • Heavy menstruation
  • Endurance athletes

Stacks well with: Vitamin C

Common uses

  • Liver protection
  • Lung health
  • OCD / mental health
  • PCOS

Stacks well with: Vitamin C, Selenium (Selenomethionine)

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.