Is a higher dose always better?

No. Dose-fit rewards landing inside the range studied for the outcome — over-dosing (common with melatonin) or under-dosing both lower the score. The goal is the effective dose, not the biggest number.

What does the Value score mean?

The Value score compares a product's price per serving with clinically relevant products ranked for the same outcome. A score of 50 is the typical price; above 50 means better value than typical, while below 50 means the product costs more than typical. It is a 0–100 value signal, not a percentile.

Why is the cheapest product not #1?

Cost is only one input. The cheapest pick here is a citrate form with weaker absorption and a stock-risk flag, so it leads on Value-for-cost but trails on the composite that also weighs evidence, dose fit and availability.

Are these affiliate links?

Retailer links may be affiliate links and DoseRank may earn a commission. Rankings and placement are determined by the scoring model only — never by payment from a brand.

Is this medical advice?

No. DoseRank summarizes evidence to help you choose; it is not a substitute for a clinician, especially if you are pregnant, breastfeeding, on medication, or managing a health condition.

Improve circulation

What this outcome means

Peripheral circulation is how well blood reaches your hands, feet, and the tissues farthest from your heart. On DoseRank it maps to a defined health outcome built from human studies on limb blood flow, skin temperature, and ankle-brachial measures – data sourced from open sources and specialized resources. DoseRank is not medical advice.

Who it's for

Cold hands and feetFingers and toes that stay chilly even in warm rooms.

Numb or tingling limbsPins-and-needles in the extremities after sitting still.

Heavy, tired legsAching or sluggish legs during long stretches of standing.

Stack buildersAlready taking supplements such as Propionyl-L-Carnitine and want the dose right.

Evidence level

92Strong

Propionyl-L-Carnitine – has strong public evidence. DoseRank looks at both evidence quality and formula fit. A DoseFit Score of 78 means this product's ingredient forms and doses are close to what was used in the studies behind this ranking - DoseRank weights each product ingredient.

Best ingredients

Propionyl-L-Carnitine is the best supported ingredient signal for this outcome.

Dose matchedDoseFit 78

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: In range: Propionyl-L-Carnitine 2 g vs 1-3 g.

Processed

346

Available

346

Ingredients

Brands

Coverage

100%

How to read the scores

What every metric means

Each score is 0–100. Higher is better for every metric below.

CompositeThe overall DoseRank score — a weighted blend of clinical strength, evidence, dose fit, trust and value.Higher is better

ClinicalHow strongly the formula's ingredients and doses match what clinical studies used for this outcome.Higher is better

EvidenceHow much published human research backs the formula's key ingredients for this outcome — both how many studies exist and how strong they are.Higher is better

ValueHow the price per serving compares with similar products for this outcome — 50 is the typical price, higher means better value for your money.Higher is better

TrustHow well customers rate this product, with extra weight given to ratings backed by a large number of reviews.Higher is better

PopularityHow strongly this product sells compared with the other ranked products for this outcome.Higher is better

This legend covers the scores on this page — for data sources, scoring weights, and limits, read the full methodology →

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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

Frequently asked

Each product gets a composite score blending clinical strength, evidence, dose fit, trust and value. 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.

Improve circulation

What this outcome means

Who it's for

Cold hands and feetFingers and toes that stay chilly even in warm rooms.

Numb or tingling limbsPins-and-needles in the extremities after sitting still.

Heavy, tired legsAching or sluggish legs during long stretches of standing.

Stack buildersAlready taking supplements such as Propionyl-L-Carnitine and want the dose right.

Evidence level

92Strong

Best ingredients

Propionyl-L-Carnitine is the best supported ingredient signal for this outcome.

Dose matchedDoseFit 78

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: In range: Propionyl-L-Carnitine 2 g vs 1-3 g.

Processed

346

Available

346

Ingredients

Brands

Coverage

100%

Relevant ingredients

Which ingredient types matter for peripheral circulationOpen to see which ingredient types matter for peripheral circulation

1 products across 1 ingredient types — open to filter the ranking.

Use types to filter ranked products

Amino Acids & Derivatives

1 product

The building blocks of protein, taken singly for targeted effects – leucine for muscle, theanine for calm. Free-form versions absorb fast on an empty stomach.

Typical:

Top decision cards

Best products for peripheral circulation

Ranking by · Composite outcome score

Best overall — the composite outcome score.

Top pick · DoseRank

Why this ranks #1 for peripheral circulation

Life Enhancement, PropeL™, 240 Vegetarian Capsules

Life Enhancement$2.18 / serving4.4 · 117Available now

Also helps with

Neuropathy symptoms

Angina symptoms

Antioxidant capacity

Why this ranks here

Evidence fitPropionyl-L-Carnitine is the strongest evidence signal for this outcome.
Dose fitPropionyl-L-Carnitine at 2 g lands inside the studied 1-3 g window.
Price / serving$2.18 per serving — high price tier for this outcome.
AvailabilityIn stock across major retailers; 99% availability confidence.
TrustLimited trust signals so far for this listing.

The numbers

2 gIn rangeinside the studied 1-3 g window

2 g

600 mg

Compare top 3 Product data Open at retailer

The rest of the ranking · DoseRank

Top 10 ranked products

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Solaray, Cool Cayenne™, 180 VegCaps (300 mg per Capsule)

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Solaray, Extra Hot Cool Cayenne, 90 VegCaps (300 mg per VegCap)

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Vitacost, Cayenne Pepper, 180 Capsules (300 mg per Capsule)

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Solaray, True Herbs, Cayenne, 515 mg, 180 VegCaps

SolarayClinical4Dose fit67Popularity30$0.08/ serving

Solaray, True Herbs, Cayenne, 515 mg, 100 VegCaps

SolarayClinical4Dose fit67Popularity30$0.10/ serving

Swanson Vitamins, Garlic with Cayenne , 200 Capsules

Swanson VitaminsClinical4Dose fit67Popularity30$0.19/ serving