Betaine Anhydrous vs Magnesium L-Threonate

Performance vs Sleep · evidence-backed comparison

Quick take
  • Betaine Anhydrous has the stronger evidence base (moderate (some rcts)).
  • Betaine Anhydrous is cheaper per serving ($0.25 vs $1.10).
  • Magnesium L-Threonate has higher bioavailability (better absorption).

Side-by-side traits

TraitBetaine AnhydrousMagnesium L-Threonate
Category
PerformanceSleep
Active compound
TrimethylglycineMagnesium L-threonate
Form available
Powder, CapsuleCapsule, Powder
Source
plantsynthetic
Typical dose
2.5 g daily1.5–2 g (≈144 mg elemental Mg)
Dose range
2.5 g1500–2000 mg
Loading protocol
Best taken with
with mealsevening
Best time of day
anyevening
Bioavailability
How efficiently the body absorbs and utilizes the compound.
High (4/5)Very High (5/5)
Onset time
Cumulative: 2–6 weeksCumulative: 4–12 weeks
Half-life
~14 hours
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
Moderate (3/5)Very Low (1/5)
Physical energy
Moderate (3/5)Very Low (1/5)
Focus / cognition
Low (2/5)High (4/5)
Mood / stress
Low (2/5)Moderate (3/5)
Sleep quality
Very Low (1/5)High (4/5)
Immunity
Very Low (1/5)Very Low (1/5)
Recovery
Post-exercise recovery support.
Moderate (3/5)Very Low (1/5)
Longevity / healthspan
Moderate (3/5)Moderate (3/5)
Safety rating
5 = exceptionally well-tolerated; 1 = significant risk profile.
Very High (5/5)Very High (5/5)
Price per serving
Approximate USD per typical daily dose.
$0.25$1.10
Vegan friendly
YesYes
Gluten free
YesYes
3rd-party tested
YesYes

About Betaine Anhydrous

Methyl donor that supports homocysteine recycling and may modestly boost power output. Often paired with creatine in pre-workout formulas.

Active compound: Trimethylglycine
Forms: Powder, Capsule
Onset: Cumulative: 2–6 weeks
powermethylationliverhomocysteine

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

Betaine Anhydrous safety

Common side effects:

  • Fishy body odor (rare)

Avoid if:

  • Kidney disease

Magnesium L-Threonate safety

Common side effects:

  • Drowsiness
  • Headache (rare)

Avoid if:

  • Severe kidney disease

Drug interactions:

  • Bisphosphonates

Common uses

  • Power output
  • Homocysteine support
  • Liver health

Stacks well with: Creatine Monohydrate, Vitamin B12 (Methylcobalamin)

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.