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.

Reduce muscle weakness

What this outcome means

Muscle weakness is when your muscles can't produce the force they should, leaving everyday lifting and movement harder than it once was. On DoseRank it maps to a defined health outcome built from human studies on grip strength, force output, and physical performance measures – data sourced from open sources and specialized resources. DoseRank is not medical advice.

Who it's for

Losing strengthEveryday lifting and carrying that now feels heavier.

Age-related declineMuscle and power fading gradually through later decades.

Recovery and disuseStrength lost after illness, bed rest, or immobilization.

Stack buildersAlready taking supplements such as Vitamin D or Phosphorus and want the dose right.

Evidence level

78Moderate-strong

Vitamin D and Phosphorus – have 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

Vitamin D and Phosphorus are the best supported ingredient signals for this outcome.

Dose matchedDoseFit 90

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: In range: Vitamin D 5000 IU vs 1000-5000 IU; Below range: Phosphorus 85 mg vs 500-1000 mg.

Processed

2.4k

Available

2.4k

Ingredients

Brands

332

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 →

Not sure which is right for you?

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Take 60-sec quiz

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.

Reduce muscle weakness

What this outcome means

Who it's for

Losing strengthEveryday lifting and carrying that now feels heavier.

Age-related declineMuscle and power fading gradually through later decades.

Recovery and disuseStrength lost after illness, bed rest, or immobilization.

Stack buildersAlready taking supplements such as Vitamin D or Phosphorus and want the dose right.

Evidence level

78Moderate-strong

Best available ingredients

Vitamin D and Phosphorus are the best supported ingredient signals for this outcome.

Dose matchedDoseFit 90

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: In range: Vitamin D 5000 IU vs 1000-5000 IU; Below range: Phosphorus 85 mg vs 500-1000 mg.

Processed

2.4k

Available

2.4k

Ingredients

Brands

332

Coverage

100%

Relevant ingredients

Which ingredient types matter for muscle weaknessOpen to see which ingredient types matter for muscle weakness

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

Use types to filter ranked products

Vitamins

452 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:

Top decision cards

Best products for muscle weakness

Ranking by · Composite outcome score

Best overall — the composite outcome score.

Top pick · DoseRank

Why this ranks #1 for muscle weakness

Solaray, Vitamin D3 + K2, 60 VegCaps

Solaray$0.31 / serving4.9 · 92,933Available now

Also helps with

Vitamin K status

Immune function

Respiratory infection incidence

Why this ranks here

Evidence fitVitamin D and Phosphorus have moderate human evidence for this outcome.
Dose fit1 of 2 dosed ingredients land in the studied range. Vitamin D at 5000 IU lands inside the studied 1000-5000 IU window.
Price / serving$0.31 per serving — mid price tier for this outcome.
AvailabilityIn stock across major retailers; 99% availability confidence.
TrustStrong trust signals — consistently high marks from verified buyer ratings.

The numbers

5000 IUIn rangeinside the studied 1000-5000 IU window

85 mgBelow rangebelow the studied 500-1000 mg window

110 mg

50 mcg

Compare top 3 Product data Open at retailer

The rest of the ranking · DoseRank

Top 10 ranked products

Solaray, Super Bio Vitamin D-3, 125 mcg, 120 Softgels

SolarayClinical81Dose fit90Popularity30$0.12/ serving

Solaray, Kids Vitamins & Minerals Chewable, Natural Black Cherry, 60 Chewables

SolarayClinical78Dose fit67Popularity76$0.28/ serving

Nature's Life, Super D-3, 100 mcg, 100 Softgels

Nature's LifeClinical80Dose fit84Popularity30$0.12/ serving

Nature's Life, Ultra D-3, 250 mcg , 100 Softgels

Nature's LifeClinical81Dose fit93Popularity30$0.18/ serving

LifeTime Vitamins, VitaLiquids, Bone Support, Strawberry, 16 fl oz (473 ml)

LifeTime VitaminsClinical78Dose fit67Popularity50$0.50/ serving

LifeTime Vitamins, Bone Support, Orange Vanilla, 16 fl oz (473 ml)

LifeTime VitaminsClinical78Dose fit67Popularity50$0.50/ serving

Solaray, Vitamin D-3 Lozenges, Natural Lemon, 50 mcg, 60 Lozenges

SolarayClinical78Dose fit73Popularity30$0.15/ serving

Nature's Life, Mighty Mini Vite, Daily Multivitamin, 240 Micro Tablets

Nature's LifeClinical78Dose fit67Popularity30$0.15/ serving

Solaray, Cal-Mag Citrate 2:1 Ratio, 180 Capsules

SolarayClinical78Dose fit67Popularity50$0.76/ serving