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 vascular function

What this outcome means

Vascular function is how well your blood vessels widen, narrow, and respond as blood moves through your body during rest and effort. On DoseRank it maps to a defined health outcome built from human studies on flow-mediated dilation, arterial stiffness, and endothelial reactivity – data sourced from open sources and specialized resources. DoseRank is not medical advice.

Who it's for

Stiffening with ageOlder arteries that have grown less elastic and slower to respond.

Sedentary circulationLong sitting days and little movement that leave vessels sluggish.

Watching the numbersPeople tracking blood pressure and vascular markers at routine checkups.

Stack buildersAlready taking supplements such as Grape Seed Extract and want the dose right.

Evidence level

78Moderate-strong

Grape Seed Extract – has moderate public evidence for this outcome. This usually means there are smaller or mechanistic studies, but not randomized human trials. A DoseFit Score of 90 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 available ingredients

Grape Seed Extract is the best supported ingredient signal for this outcome.

Dose matchedDoseFit 90

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: In range: Grape Seed Extract 400 mg vs 150-400 mg.

Processed

2.7k

Available

2.7k

Ingredients

Brands

298

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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Get a personal report

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 vascular function

What this outcome means

Who it's for

Stiffening with ageOlder arteries that have grown less elastic and slower to respond.

Sedentary circulationLong sitting days and little movement that leave vessels sluggish.

Watching the numbersPeople tracking blood pressure and vascular markers at routine checkups.

Stack buildersAlready taking supplements such as Grape Seed Extract and want the dose right.

Evidence level

78Moderate-strong

Best available ingredients

Grape Seed Extract is the best supported ingredient signal for this outcome.

Dose matchedDoseFit 90

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: In range: Grape Seed Extract 400 mg vs 150-400 mg.

Processed

2.7k

Available

2.7k

Ingredients

Brands

298

Coverage

100%

Relevant ingredients

Which ingredient types matter for vascular functionOpen to see which ingredient types matter for vascular function

2.5k products across 5 ingredient types — open to filter the ranking.

Use types to filter ranked products

Botanicals/Herbal Extracts

296 products

Concentrated plant and herbal extracts standardized to actives. Potency depends on the extract ratio and marker content, not raw weight.

Typical: ,

Minerals & Trace Elements

408 products

Inorganic nutrients from calcium to zinc. The chemical form drives absorption – chelates and citrates usually beat cheap oxides.

Typical:

Vitamins

837 products

Essential micronutrients the body can't make in sufficient amounts. Fat-soluble ones (A, D, E, K) store up; water-soluble ones need regular topping-up.

Typical:

Amino Acids & Derivatives

537 products

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:

Antioxidants & Bioactive Compounds

393 products

Molecules that neutralize free radicals and tune cell signaling. Helpful in balance; mega-doses can blunt the body's own adaptive defenses.

Top decision cards

Best products for vascular function

Ranking by · Composite outcome score

Best overall — the composite outcome score.

Top pick · DoseRank

Why this ranks #1 for vascular function

Nutricost, Grape Seed Extract, 240 Capsules (400 mg per Capsule)

Nutricost$0.07 / serving4.7 · 1,128Available now

Also helps with

Blood pressure

Antioxidant capacity

Oxidative stress biomarkers

Why this ranks here

Evidence fitGrape Seed Extract has moderate human evidence for this outcome.
Dose fitGrape Seed Extract at 400 mg lands inside the studied 150-400 mg window.
Price / serving$0.07 per serving — low price tier for this outcome.
AvailabilityIn stock across major retailers; 99% availability confidence.
TrustSolid trust signals from buyer ratings, with room to grow.

The numbers

400 mgIn rangeinside the studied 150-400 mg window

Compare top 3 Product data Open at retailer

The rest of the ranking · DoseRank

Top 10 ranked products

California Gold Nutrition, Vitamin D3 + K2 as MK-7, 180 Veggie Capsules

California Gold NutritionClinical85Dose fit69Popularity100$0.08/ serving

Nutricost, Vitamin K2 MK-7, 100 mcg, 240 Softgels

NutricostClinical85Dose fit68Popularity99$0.07/ serving

Metabolic Nutrition, Vitamin D3 + K2, 90 Capsules

Metabolic NutritionClinical86Dose fit76Popularity89$0.11/ serving

Micro Ingredients, Vitamin D3 & K2, 300 Softgels

Micro IngredientsClinical86Dose fit76Popularity96$0.10/ serving

Micro Ingredients, Vitamin K2, MK-7, 200 mcg, 300 Softgels

Micro IngredientsClinical86Dose fit76Popularity91$0.07/ serving

NOW Foods, Grape Seed Extract, 500 mg, 90 Veg Capsules

NOW FoodsClinical88Dose fit91Popularity84$0.26/ serving

Codeage, A, D, K Vitamins+, 180 Vegetable Capsules

CodeageClinical88Dose fit94Popularity84$0.22/ serving

Nutricost, Vitamin K2 + Vitamin D3, 120 Softgels

NutricostClinical85Dose fit68Popularity98$0.11/ serving

NOW Foods, Mega D3 & MK-7, 120 Capsules

NOW FoodsClinical86Dose fit74Popularity99$0.22/ serving