Krill Oil vs L-Tryptophan

Omega / Fatty Acid vs Sleep · evidence-backed comparison

Quick take
  • Krill Oil has the broader effect profile across the 9 effect categories.
  • L-Tryptophan is cheaper per serving ($0.35 vs $0.80).
  • Krill Oil has higher bioavailability (better absorption).

Side-by-side traits

TraitKrill OilL-Tryptophan
Category
Omega / Fatty AcidSleep
Active compound
Phospholipid-bound EPA/DHA + astaxanthinL-tryptophan
Form available
SoftgelCapsule, Powder
Source
marinemicrobial
Typical dose
1–2 g daily (≈ 0.3 g EPA+DHA)500–1500 mg
Dose range
1–2 g500–1500 mg
Loading protocol
Best taken with
with foodcarbs (improves CNS uptake), empty stomach
Best time of day
anyevening
Bioavailability
How efficiently the body absorbs and utilizes the compound.
Very High (5/5)Moderate (3/5)
Onset time
Cumulative: 4–12 weeksAcute: 60 min
Half-life
~2 hours
Evidence level
Quality and quantity of human research.
Moderate (some RCTs)Moderate (some RCTs)
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
Moderate (3/5)Very Low (1/5)
Mood / stress
Moderate (3/5)High (4/5)
Sleep quality
Low (2/5)High (4/5)
Immunity
Low (2/5)Very Low (1/5)
Recovery
Post-exercise recovery support.
Moderate (3/5)Very Low (1/5)
Longevity / healthspan
High (4/5)Very Low (1/5)
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.
$0.80$0.35
Vegan friendly
NoYes
Gluten free
YesYes
3rd-party tested
YesYes

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

About L-Tryptophan

Serotonin and melatonin precursor. Generally safer than 5-HTP for daily use, with strong sleep-onset and mood support.

Active compound: L-tryptophan
Forms: Capsule, Powder
Onset: Acute: 60 min
serotoninmoodsleep-onset

Krill Oil safety

Common side effects:

  • No fishy burps
  • Mild GI upset (rare)

Avoid if:

  • Crustacean allergy
  • Bleeding disorders

Drug interactions:

  • Anticoagulants

L-Tryptophan safety

Common side effects:

  • Drowsiness
  • GI upset
  • Dry mouth

Avoid if:

  • SSRI use (serotonin syndrome)
  • Liver disease

Drug interactions:

  • SSRIs
  • MAOIs
  • Sedatives

Common uses

  • Heart health
  • Joint inflammation
  • Eye health

Stacks well with: Vitamin D3

Common uses

  • Sleep onset
  • Mood
  • Carb cravings

Stacks well with: Magnesium Glycinate

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.