Magnesium Citrate vs Magnesium L-Threonate

Sleep vs Sleep · evidence-backed comparison

Quick take
  • Magnesium Citrate has the stronger evidence base (moderate (some rcts)).
  • Magnesium L-Threonate has the broader effect profile across the 9 effect categories.
  • Magnesium Citrate is cheaper per serving ($0.12 vs $1.10).
  • Magnesium L-Threonate has a slightly cleaner safety profile.
  • Magnesium L-Threonate has higher bioavailability (better absorption).

Side-by-side traits

TraitMagnesium CitrateMagnesium L-Threonate
Category
SleepSleep
Active compound
Magnesium citrateMagnesium L-threonate
Form available
Capsule, Powder, Tablet, LiquidCapsule, Powder
Source
syntheticsynthetic
Typical dose
200–400 mg elemental Mg1.5–2 g (≈144 mg elemental Mg)
Dose range
200–400 mg1500–2000 mg
Loading protocol
Best taken with
any time, with waterevening
Best time of day
anyevening
Bioavailability
How efficiently the body absorbs and utilizes the compound.
High (4/5)Very High (5/5)
Onset time
Acute: 1–3 hoursCumulative: 4–12 weeks
Half-life
Evidence level
Quality and quantity of human research.
Moderate (some RCTs)Limited (small studies)
Overall effect
Subjective effect magnitude.
Moderate (3/5)Moderate (3/5)
Muscle / strength
Low (2/5)Very Low (1/5)
Physical energy
Low (2/5)Very Low (1/5)
Focus / cognition
Very Low (1/5)High (4/5)
Mood / stress
Low (2/5)Moderate (3/5)
Sleep quality
Moderate (3/5)High (4/5)
Immunity
Very Low (1/5)Very Low (1/5)
Recovery
Post-exercise recovery support.
Low (2/5)Very Low (1/5)
Longevity / healthspan
Moderate (3/5)Moderate (3/5)
Safety rating
5 = exceptionally well-tolerated; 1 = significant risk profile.
High (4/5)Very High (5/5)
Price per serving
Approximate USD per typical daily dose.
$0.12$1.10
Vegan friendly
YesYes
Gluten free
YesYes
3rd-party tested
YesYes

About Magnesium Citrate

Most affordable absorbable magnesium. Doubles as a mild laxative — useful if constipated, less ideal if not.

Active compound: Magnesium citrate
Forms: Capsule, Powder, Tablet, Liquid
Onset: Acute: 1–3 hours
sleepconstipationvaluemuscle

About Magnesium L-Threonate

Only magnesium form proven to cross the blood-brain barrier in animals. Marketed for cognitive aging and sleep, but premium-priced.

Active compound: Magnesium L-threonate
Forms: Capsule, Powder
Onset: Cumulative: 4–12 weeks
brainsleepmemoryblood-brain-barrier

Magnesium Citrate safety

Common side effects:

  • Loose stools (often desired)
  • GI cramps

Avoid if:

  • Severe kidney disease

Drug interactions:

  • Bisphosphonates

Magnesium L-Threonate safety

Common side effects:

  • Drowsiness
  • Headache (rare)

Avoid if:

  • Severe kidney disease

Drug interactions:

  • Bisphosphonates

Common uses

  • General magnesium repletion
  • Constipation
  • Sleep

Stacks well with: Vitamin D3

Common uses

  • Cognitive aging
  • Deep sleep
  • Memory

Stacks well with: Zinc, Vitamin D3

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.