Vitamin D-3, High Potency, 2,000 IU, 240 Softgels vs Vitamin D3 5000 IU
Side-by-side comparison of scores, ingredients, prices and real customer feedback for Vitamin D-3, High Potency, 2,000 IU, 240 Softgels and Vitamin D3 5000 IU.
Last verified: 07 Apr 2026 · Based on 60 reviews
Vitamin D-3, High Potency, 2,000 IU, 240 Softgels scores 82.0/100 vs Vitamin D3 5000 IU at 81.0/100. Vitamin D-3, High Potency, 2,000 IU, 240 Softgels wins on value for money, side effects. Vitamin D3 5000 IU is stronger on ingredient quality and certifications.
Which is better: Vitamin D-3, High Potency, ... or Vitamin D3 5000 IU?
NOW Foods wins on price (£8.82 for 240 softgels) and value score (90 versus 66). Pick Thorne if you have a confirmed deficiency requiring 5000 IU.
— AIScored Editorial Team
How Do the Scores Compare?
Vitamin D-3, High Potency, ...
NOW Foods
|
Vitamin D3 5000 IU
Thorne
|
|
|---|---|---|
| Overall Score | 82.0 | 81.0 |
| Effectiveness |
82.0/100
Best
|
82.0/100
Best
|
| Ingredient Quality | 85.0/100 |
90.0/100
Best
|
| Value for Money |
90.0/100
Best
|
66.0/100 |
| Side Effects |
93.0/100
Best
|
80.0/100 |
| Certifications | 58.0/100 |
88.0/100
Best
|
| Best Price |
£8.82
iHerb →
Cheapest
|
View → |
| Form | None | N/A |
| Dose | None | N/A |
| Third-Party Tested | ✗ No | ✗ No |
| Reviews Analysed | 50 | 10 |
Vitamin D-3, High Potency, 2,000...
Pros
- ✓Small, tasteless softgels praised by nearly every reviewer — easy to swallow for adults and children alike
- ✓240-count bottle lasts 8 months at one per day, making the per-dose cost very low
- ✓Cholecalciferol delivered in olive oil — correct form and carrier for fat-soluble vitamin absorption
- ✓Reviewers consistently report energy, mood, and immunity improvements over autumn-winter use
Cons
- ✗Bovine gelatin capsule rules out vegans and some vegetarians — no plant-based equivalent in this line
- ✗No independent third-party potency or purity testing (no iTested, NSF, or USP verification)
- ✗2,000 IU is a maintenance dose, not a correction dose — several reviewers with confirmed deficiency needed higher amounts or separate high-dose protocols
- ✗One reviewer flagged the lid pops open unexpectedly rather than staying sealed between uses
Best For
Vitamin D3 5000 IU
Pros
- ✓Thorne Research is NSF Certified for Sport — independently tested for purity and label accuracy
- ✓Cholecalciferol (D3) is the most bioavailable and research-supported form of vitamin D
- ✓D3+K2 MK7 combination helps direct calcium to bones rather than arteries — evidence-backed synergy
- ✓Liquid format (30ml) allows flexible dosing and faster absorption than capsules
Cons
- ✗5000 IU is a high therapeutic dose — not appropriate for general daily use without a confirmed deficiency test
- ✗Premium price point compared to generic D3 supplements
- ✗Liquid format requires careful dosing to avoid over-supplementation
- ✗Fat-soluble vitamin — must be taken with a meal containing fat for optimal absorption
Best For
What does the data say about Vitamin D-3, High Pote... vs Vitamin D3 5000 IU?
These two products solve different problems. Thorne's 5000 IU is a therapeutic dose for confirmed deficiency or severely reduced sun exposure. NOW Foods' 2,000 IU is a maintenance dose for daily prevention. This dosage difference explains why Thorne scores higher on ingredient quality (90.0 vs 81.0) and effectiveness (82.0 vs 78.0). NOW Foods wins decisively on value (91.0 vs 66.0), with 240 softgels lasting roughly 8 months at one daily dose.
Thorne includes vitamin K2 MK7 alongside D3, directing calcium to bones rather than arteries. NOW Foods omits K2 and uses extra virgin olive oil as a fat carrier for absorption. Both use cholecalciferol, the correct D3 form.
For most UK households seeking affordable daily supplementation through winter, NOW Foods at £8.82 represents genuine value. If you've tested low on vitamin D and want higher potency with calcium-directing synergies, Thorne is the pick.
NOW Foods delivers 2,000 IU of cholecalciferol — the most bioavailable form of vitamin D — suspended in olive oil inside a small bovine gelatin softgel.
What are the key differences?
Frequently Asked Questions
Which is better, Vitamin D-3, High Potency, 2,000 IU, 240 Softgels or Vitamin D3 5000 IU? ▼
Is Vitamin D-3, High Potency, 2,000 IU, 240 Softgels worth the price compared to Vitamin D3 5000 IU? ▼
Which has fewer side effects? ▼
Related Product Comparisons
Nutri Advanced Vitamin D3 with K2 Liquid Drops 30ml
vs Vitamin D-3, High Potency, 2,000 IU, 240 Softgels
Nutri Advanced Vitamin D3 with K2 Liquid Drops 30ml
vs Vitamin D3 5000 IU
Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count
vs Vitamin D-3, High Potency, 2,000 IU, 240 Softgels
Solgar Vitamin D3 1000 IU (25mcg) Softgels - 250 Count
vs Vitamin D3 5000 IU
Vitamin D-3, High Potency, 2,000 IU, 240 Softgels
vs Vitamin D-3, High Potency, 5,000 IU, 120 Softgels
Vitamin D-3, High Potency, 2,000 IU, 240 Softgels
vs Vitamin D-3, High Potency, 5,000 IU, 240 Softgels
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.
Feedback & Suggestions
Spotted an issue? Wrong price, incorrect data, or something else off? Let us know and we'll fix it.
Missing a product you'd like us to review? Tell us the product name and we'll consider adding it.