Iodine (Potassium Iodide) vs Magnesium Citrate

Mineral vs Sleep · evidence-backed comparison

Quick take
  • Iodine (Potassium Iodide) has the stronger evidence base (strong (multiple rcts / meta-analyses)).
  • Magnesium Citrate has the broader effect profile across the 9 effect categories.
  • Iodine (Potassium Iodide) is cheaper per serving ($0.05 vs $0.12).
  • Magnesium Citrate has a slightly cleaner safety profile.
  • Iodine (Potassium Iodide) has higher bioavailability (better absorption).

Side-by-side traits

TraitIodine (Potassium Iodide)Magnesium Citrate
Category
MineralSleep
Active compound
Potassium iodideMagnesium citrate
Form available
Capsule, Tablet, LiquidCapsule, Powder, Tablet, Liquid
Source
mineralsynthetic
Typical dose
150 mcg daily200–400 mg elemental Mg
Dose range
150–300 mcg200–400 mg
Loading protocol
Best taken with
with foodany time, with water
Best time of day
morningany
Bioavailability
How efficiently the body absorbs and utilizes the compound.
Very High (5/5)High (4/5)
Onset time
Cumulative: 2–8 weeksAcute: 1–3 hours
Half-life
Evidence level
Quality and quantity of human research.
Strong (multiple RCTs / meta-analyses)Moderate (some RCTs)
Overall effect
Subjective effect magnitude.
Low (2/5)Moderate (3/5)
Muscle / strength
Very Low (1/5)Low (2/5)
Physical energy
Low (2/5)Low (2/5)
Focus / cognition
Very Low (1/5)Very Low (1/5)
Mood / stress
Low (2/5)Low (2/5)
Sleep quality
Very Low (1/5)Moderate (3/5)
Immunity
Low (2/5)Very Low (1/5)
Recovery
Post-exercise recovery support.
Very Low (1/5)Low (2/5)
Longevity / healthspan
Low (2/5)Moderate (3/5)
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.
$0.05$0.12
Vegan friendly
YesYes
Gluten free
YesYes
3rd-party tested
YesYes

About Iodine (Potassium Iodide)

Essential for thyroid hormone synthesis. Iodized salt usually covers needs; supplement only if confirmed deficient.

Active compound: Potassium iodide
Forms: Capsule, Tablet, Liquid
Onset: Cumulative: 2–8 weeks
thyroiddeficiency-correctionpregnancy

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

Iodine (Potassium Iodide) safety

Common side effects:

  • Acne
  • Hyperthyroidism (high doses)
  • Goitre (paradox)

Avoid if:

  • Hyperthyroid
  • Graves' disease
  • Hashimoto's (caution)

Drug interactions:

  • Lithium
  • Anti-thyroid drugs

Magnesium Citrate safety

Common side effects:

  • Loose stools (often desired)
  • GI cramps

Avoid if:

  • Severe kidney disease

Drug interactions:

  • Bisphosphonates

Common uses

  • Thyroid support
  • Pregnancy
  • Iodine deficiency

Stacks well with: Selenium (Selenomethionine)

Common uses

  • General magnesium repletion
  • Constipation
  • Sleep

Stacks well with: 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.