The short answer · Muscle weakness
Take vitamin d & phosphorus for muscle weakness. This is the one to buy.
Solaray, Vitamin D3 + K2, 60 VegCaps
4.9· 93,142 ratings· $0.28/serving
Vitamin D 5000 IU — inside the studied 1000-5000 IU window
Of 2,245 products scored for Muscle weakness, Solaray, Vitamin D3 + K2, 60 VegCaps ranks #1 with a DoseRank score of 78. Vitamin D and Phosphorus have moderate human evidence for this outcome.
Retailer links may be affiliate links. Rankings and placement are never paid.
The form“Why Vitamin D & Phosphorus?”Evidence Moderate evidence
Vitamin D and Phosphorus have moderate human evidence for this outcome.
- Vitamin DThe pick
Moderate evidence · 5000 IU
Fat-soluble vitamin made in skin from sunlight; needed for calcium absorption, bone health, and immune modulation, and widely deficient in low-sun regions.
- PhosphorusThe pick
Moderate evidence · 85 mg
Essential mineral tracked on nutrition labels; critical for bone and tooth mineralization, ATP energy production, and cell membrane phospholipids.
The dose“Is the dose actually effective?”Dose fit 90
1 of 2 dosed ingredients land in the studied range. Vitamin D at 5000 IU lands inside the studied 1000-5000 IU window.
Vitamin D
Studied window 1000-5000 IU · this pick 5000 IU
Phosphorus
Studied window 500-1000 mg · this pick 85 mg
The ranking“Why should I trust this pick?”Trust 97
Strong trust signals — consistently high marks from verified buyer ratings. Each product gets a DoseRank score blending clinical strength, evidence, dose fit, trust and value. Retailer links may be affiliate links — the scoring model decides placement, never payment from a brand.
- 2,245 products scored
- Never paid placement
- Evidence level: Moderate · 78
- 322 brands
- 6 ingredients
The price“Can I do better than $0.28 a serving?”Value 72
$0.28 per serving — mid price tier for this outcome. The cheapest ranked pick here is $0.12 per serving.
- 2Solaray, Super Bio Vitamin D-3, 125 mcg, 120 SoftgelsScore 74 · $0.12/servingiHerb
- 4Nature's Life, Super D-3, 100 mcg, 100 SoftgelsScore 73 · $0.12/servingiHerb
Why not the absolute cheapest? The DoseRank score also weighs clinical strength, evidence, dose fit and trust — the very cheapest listings rarely hold up everywhere else.
Ready?
The #1 pick is $0.28 a serving.Solaray, Vitamin D3 + K2, 60 VegCaps — in stock at a tracked retailer.
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Solaray, Vitamin D3 + K2, 60 VegCaps ranks #1 for Muscle weakness with a DoseRank score of 78. The score blends clinical strength, evidence, dose fit, trust signals and value across 2,245 products scored for this outcome.
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