Methylfolate (5-MTHF) vs Krill Oil

Vitamin vs Omega / Fatty Acid · evidence-backed comparison

Quick take
  • Methylfolate (5-MTHF) has the stronger evidence base (strong (multiple rcts / meta-analyses)).
  • Krill Oil has the broader effect profile across the 9 effect categories.
  • Methylfolate (5-MTHF) is cheaper per serving ($0.22 vs $0.80).

Side-by-side traits

TraitMethylfolate (5-MTHF)Krill Oil
Category
VitaminOmega / Fatty Acid
Active compound
L-5-methyltetrahydrofolatePhospholipid-bound EPA/DHA + astaxanthin
Form available
Capsule, TabletSoftgel
Source
syntheticmarine
Typical dose
400–1000 mcg daily1–2 g daily (≈ 0.3 g EPA+DHA)
Dose range
400–1000 mcg1–2 g
Loading protocol
Best taken with
with foodwith food
Best time of day
morningany
Bioavailability
How efficiently the body absorbs and utilizes the compound.
Very High (5/5)Very High (5/5)
Onset time
Cumulative: 4–8 weeksCumulative: 4–12 weeks
Half-life
~3 hours
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
Moderate (3/5)Low (2/5)
Focus / cognition
Moderate (3/5)Moderate (3/5)
Mood / stress
High (4/5)Moderate (3/5)
Sleep quality
Very Low (1/5)Low (2/5)
Immunity
Low (2/5)Low (2/5)
Recovery
Post-exercise recovery support.
Very Low (1/5)Moderate (3/5)
Longevity / healthspan
Moderate (3/5)High (4/5)
Safety rating
5 = exceptionally well-tolerated; 1 = significant risk profile.
High (4/5)High (4/5)
Price per serving
Approximate USD per typical daily dose.
$0.22$0.80
Vegan friendly
YesNo
Gluten free
YesYes
3rd-party tested
YesYes

About Methylfolate (5-MTHF)

Pre-methylated folate that bypasses MTHFR variants. Essential during pregnancy and for treatment-resistant depression with low folate.

Active compound: L-5-methyltetrahydrofolate
Forms: Capsule, Tablet
Onset: Cumulative: 4–8 weeks
moodMTHFRpregnancyhomocysteine

About Krill Oil

Phospholipid-bound omega-3s with included astaxanthin. Better absorbed per gram than fish oil but ~3× the price for same EPA/DHA.

Active compound: Phospholipid-bound EPA/DHA + astaxanthin
Forms: Softgel
Onset: Cumulative: 4–12 weeks
heartbrainphospholipidastaxanthin

Methylfolate (5-MTHF) safety

Common side effects:

  • Anxiety / irritability (over-methylation)
  • Insomnia (PM use)

Avoid if:

  • Bipolar disorder

Drug interactions:

  • Methotrexate
  • Antiseizure meds

Krill Oil safety

Common side effects:

  • No fishy burps
  • Mild GI upset (rare)

Avoid if:

  • Crustacean allergy
  • Bleeding disorders

Drug interactions:

  • Anticoagulants

Common uses

  • Pregnancy
  • MTHFR variants
  • Depression
  • Homocysteine

Stacks well with: Vitamin B12 (Methylcobalamin), Betaine Anhydrous

Common uses

  • Heart health
  • Joint inflammation
  • Eye health

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.