Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count vs Vitamin D-3, High Potency, 5,000 IU, 240 Softgels
Side-by-side comparison of scores, ingredients, prices and real customer feedback for Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count and Vitamin D-3, High Potency, 5,000 IU, 240 Softgels.
Last verified: 07 Apr 2026 · Based on 106 reviews
Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count scores 83.0/100 vs Vitamin D-3, High Potency, 5,000 IU, 240 Softgels at 82.0/100. Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count wins on ingredient quality, side effects, certifications. Vitamin D-3, High Potency, 5,000 IU, 240 Softgels is stronger on effectiveness and value for money.
Which is better: Solgar Vitamin D3 1000 IU (... or Vitamin D-3, High Potency, ...?
Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count wins with its higher overall score of 83.0/100 versus 82.0/100 for NOW Foods Vitamin D-3, High Potency, 5,000 IU, 240 Softgels, at a lower price of £11.16 against £11.93. Pick NOW Foods Vitamin D-3 if you need 5000 IU to fix a confirmed deficiency. Solgar suits daily maintenance in low-sunlight areas with its clean safflower oil formula.
— AIScored Editorial Team
How Do the Scores Compare?
Solgar Vitamin D3 1000 IU (...
Solgar
|
Vitamin D-3, High Potency, ...
NOW Foods
|
|
|---|---|---|
| Overall Score | 83.0 | 82.0 |
| Effectiveness | 81.0/100 |
85.0/100
Best
|
| Ingredient Quality |
89.0/100
Best
|
83.0/100 |
| Value for Money | 86.0/100 |
91.0/100
Best
|
| Side Effects |
92.0/100
Best
|
87.0/100 |
| Certifications |
68.0/100
Best
|
52.0/100 |
| Best Price |
£11.16
Amazon UK →
Cheapest
|
£11.93 iHerb → |
| Price per Serving | £0.04 250 servings | N/A |
| Form | Softgels | None |
| Dose | 1000 IU (25mcg) Vitamin D3 | None |
| Third-Party Tested | ✗ No | ✗ No |
| Reviews Analysed | 56 | 50 |
Solgar Vitamin D3 1000 IU (25mcg...
Pros
- ✓Small, easy-to-swallow softgels with no taste or odour — universally noted across reviews
- ✓Exceptionally clean formulation: only safflower oil and gelatin shell, no magnesium stearate or silicon dioxide
- ✓250-count bottle offers excellent long-term value — up to ~8 months supply at 1/day
- ✓Reviewers consistently report improved energy, mood, and immunity — consistent with D3 research evidence
Cons
- ✗1000 IU is a maintenance dose only — insufficient to correct deficiency; those with low D levels typically need 2000–5000 IU under guidance
- ✗Not third-party tested (e.g. NSF, Informed Sport) — limits verification for athletes or those requiring assay confirmation
- ✗Contains bovine gelatin — not suitable for vegans, vegetarians, or some religious dietary requirements (halal concerns raised by reviewers)
- ✗Safflower oil carrier is functional but not as optimal as olive oil or MCT oil for fat-soluble vitamin absorption
Best For
Vitamin D-3, High Potency, 5,000...
Pros
- ✓Cholecalciferol (D3) in olive oil — correct form and fat-soluble delivery for meaningful absorption
- ✓240 softgels at 5,000 IU is exceptional value; multiple reviewers explicitly note how long a single purchase lasts
- ✓Tiny, tasteless, odourless softgels — easy to swallow, praised consistently across dozens of reviews
- ✓Several reviewers confirm blood levels normalised after taking this at a doctor-recommended 5,000 IU dose
Cons
- ✗Not vegan — bovine gelatin capsule shell rules it out for plant-based users
- ✗No independent third-party purity or potency testing (no NSF, USP, or equivalent verification)
- ✗5,000 IU is a therapeutic dose, not a maintenance dose — appropriate only with confirmed deficiency and blood monitoring
- ✗No K2 included; several reviewers specifically flag that K2 should be taken separately to direct calcium properly
Best For
What does the data say about Solgar Vitamin D3 1000... vs Vitamin D-3, High Pote...?
The key difference here is dosage. NOW Foods delivers 5,000 IU per softgel — a therapeutic dose designed to correct deficiency — while Solgar's offering provides 1,000 IU, a maintenance level suited to topping up levels that are already adequate. Both use D3 (cholecalciferol) in softgel form with an oil base for absorption, so the delivery mechanism is broadly similar. Solgar's formulation is notably cleaner, containing just safflower oil and gelatin, whereas NOW's ingredient list is slightly longer, though neither carries third-party certification.
If your GP has flagged low vitamin D or you've had a blood test confirming deficiency, the NOW Foods option at £11.93 makes practical sense — its 5,000 IU dose can shift levels meaningfully, and reviewers regularly report normalised results. For everyone else maintaining reasonable levels through winter, Solgar's 1,000 IU at £11.16 for 250 softgels is the more appropriate choice and avoids the risk of oversupplementing without monitoring.
On practicalities, both are small, odourless softgels that are easy to tolerate daily. Neither is vegan — both use gelatin shells — so plant-based users will need to look elsewhere entirely.
Solgar Vitamin D3 1000 IU is a well-regarded maintenance-dose supplement in a 250-count softgel format, praised by reviewers for its small capsule size, easy swallowability, and clean formulation.
What are the key differences?
Frequently Asked Questions
Which is better, Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count or Vitamin D-3, High Potency, 5,000 IU, 240 Softgels? ▼
Is Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count worth the price compared to Vitamin D-3, High Potency, 5,000 IU, 240 Softgels? ▼
Which has fewer side effects? ▼
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What the Data Says
Why do 97% of UK vitamin D supplements lack third-party certification?
Only 1 out of 35 vitamin D products we scored has independent certification. That's 97% without any third-party verification of purity, potency, or label accuracy.
This is worse than most supplement categories. The reason is simple: UK law doesn't require it, and testing costs money. Most vitamin D brands sell on price alone, especially in the D3-only space where the raw ingredient is cheap. Certification adds cost that budget brands won't absorb.
What does this mean for you? Without third-party testing, you're trusting the manufacturer's label claims. A 2021 study in Nutrients found that vitamin D supplements varied from 52% to 135% of their labelled dose. That's a problem if you're relying on a specific daily intake.
Among the 35 products we scored, the top performers are all from brands with strong manufacturing track records: NOW Foods D3 5000 IU and Thorne Vitamin D + K2 both score 87/100 overall. Thorne holds the highest certification score in the category at 85/100. If independent testing matters to you, that's the product to look at.
Do you need vitamin K2 with high-dose vitamin D?
Probably yes at high doses, and our data backs the pairing. Thorne Vitamin D + K2 Liquid is the only D3+K2 combo product in our 35-product database that scores 87/100 overall, matching the top-ranked D3-only options from NOW Foods. It also holds the highest certification score in the category at 85/100.
Here's the science behind it. Vitamin D increases calcium absorption from food. Vitamin K2 activates proteins that direct that calcium into bones and teeth, keeping it out of your arteries and soft tissue. At standard doses (1000-2000 IU daily), most people get enough K2 from diet to handle the extra calcium. At 4000-5000 IU daily, the calcium load increases enough that K2 becomes a more serious consideration.
The Endocrine Society doesn't yet include K2 in its vitamin D guidelines. But a growing body of research, including a 2019 meta-analysis in International Journal of Molecular Sciences, shows the D3+K2 combination improves bone mineral density more than D3 alone.
If you eat K2-rich foods regularly (natto, hard cheese, egg yolks, chicken liver), a standalone D3 product like NOW Foods D3 5000 IU 360 Softgels (87/100) is a solid choice. If your diet is low in K2, or you're taking 4000+ IU of D3 daily, Thorne D + K2 covers both bases in one product.
Disclaimer: AIScored provides data-driven comparisons based on publicly available reviews. This is not medical advice. Affiliate links may earn us a commission at no extra cost to you.
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