Everything DoseRank tracks on the l-proline shelf — L-Lysine. The category itself is never ranked: 18 products get scored the moment you say what you want them to do.
How to read the scores
This legend covers the scores on this page — for data sources, scoring weights, and limits, read the full methodology →
Answer a few questions about your goals, habits, stack, and budget. Then, DoseRank will find the products that best match your needs based on your answers. It's free and only takes 60 seconds! No account is required.
A saved, shareable breakdown: your matched products, dose math, interaction flags to discuss with a clinician, and a price-tracked stack you can revisit.
Questions
Each product gets a composite score blending clinical strength, evidence, dose fit, trust and value — computed for the goal you picked, across this category's products. The #1 on the DoseRank tab has the highest composite; the other tabs re-rank the same products by Value, Trust, or Popularity. Placement is never paid.
Start with a goal, not a brand
Browsing l-proline supplements without a goal makes no sense — different products do different jobs, and “best” flips depending on which job you're hiring for. These are the 16 health outcomes that matter for this category. Pick yours, and the full evidence-ranked shelf loads for that goal alone.
Infection durationLength of infectious illness episodes.7 rankedModerate-strong
Skin elasticityAbility of skin to stretch and recoil.18 rankedModerate-strong
Skin aging signsVisible features such as fine lines, wrinkles, or loss of firmness.4 rankedModerate-strong
EdemaSwelling due to excess fluid accumulation.9 rankedModerate-strong
Skin hydrationMoisture content or hydration of the skin.4 rankedStrong
Oxidative stress biomarkersLaboratory indicators of oxidative damage or redox imbalance.9 rankedModerate-strong
Vascular functionOverall health and reactivity of the circulatory system.7 rankedModerate-strong
Vitamin C statusBiochemical sufficiency of ascorbic acid.5 rankedStrong
Uric acidPurine metabolism marker associated with gout and cardiometabolic risk.5 rankedModerate-strong
Dry eye symptomsIrritation, burning, or dryness of the eyes.4 rankedLimited
Antioxidant capacityMeasured ability to counter oxidative stress.9 rankedStrong
Fat oxidationUse of fat as an energy source.2 rankedModerate-strong
Common cold durationLength of cold episodes.5 rankedStrong
Blood pressureArterial pressure; direction of benefit depends on baseline status.9 rankedModerate-strong
Endothelial functionAbility of blood vessels to dilate and respond normally.6 rankedModerate-strongNothing is ranked yet — the shelf stays locked until you pick a goal.
No goal, no ranking.
A “best l-proline supplement” list without a goal would be marketing, not evidence. Pick what you want to improve and DoseRank scores all 18 products against that goal's trials.