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Vitamins · Bone & Immunity

WeightWorld Vitamin D3 K2 (MK-7) Review

June 12, 2026 · 7 min read

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WeightWorld Vitamin D3 + K2 MK-7 365 tablets bottle

2000IU Cholecalciferol + 200mcg Menaquinone — 365 Tablets, 1 Full Year Supply

  • Vitamin D3: 2000 IU per tablet
  • Vitamin K2: 200 mcg MK-7 per tablet
  • Form: 1 tablet/day
  • Tablets: 365
  • Rating: 4.6 / 5 ★

What Is WeightWorld Vitamin D3 K2?

WeightWorld Vitamin D3 K2 is a combined supplement delivering 2000IU of Cholecalciferol (Vitamin D3) and 200mcg of Menaquinone (Vitamin K2 MK-7) in a single daily tablet. The bottle contains 365 tablets — a full year's supply at one tablet per day. It holds Amazon's Choice status with a 4.6-star rating from over 7,400 verified reviews and has been purchased by more than 3,000 customers in the past month alone. The product carries EFSA-approved health claims and is manufactured in Great Britain.

Why Combine Vitamin D3 and K2?

Vitamin D3 and Vitamin K2 are often discussed separately, but they work together in a critical biological partnership. Understanding why they are combined in one tablet requires knowing what each does independently — and what happens when one is present without the other.

Vitamin D3 — 2000IU per tablet

Vitamin D3 (Cholecalciferol) is the form of Vitamin D the human body produces naturally through sun exposure. It is responsible for:

  • Regulating calcium and phosphorus absorption in the intestine
  • Supporting the maintenance of normal bones and teeth (EFSA-approved claim)
  • Contributing to normal immune system function
  • Supporting normal muscle function

A dose of 2000IU is a mid-to-high maintenance dose, appropriate for adults — especially those with limited sun exposure, darker skin tones, or who live in northern latitudes where sunlight is insufficient for adequate synthesis during winter months.

Vitamin K2 MK-7 — 200 mcg per tablet

Vitamin K2, specifically in the MK-7 (Menaquinone-7) form, is the most bioavailable and longest-acting subtype of Vitamin K2. Its primary role is to direct calcium where it belongs:

  • Into bones and teeth — supporting mineralisation and density
  • Away from soft tissues and arterial walls — where calcium deposits can cause harm

This is why combining D3 with K2 matters: D3 increases calcium absorption, and K2 ensures that calcium is deposited in the right places. Taking high-dose D3 without K2 may raise circulating calcium without adequate direction.

MK-7 vs MK-4 — Why the Form of K2 Matters

  • Half-life: MK-4 ~1–2 hours · MK-7 ~72 hours
  • Dosing frequency: MK-4 multiple times/day · MK-7 once daily
  • Bioavailability: MK-7 higher
  • Source: MK-4 synthetic · MK-7 natural (natto fermentation)

MK-7 is the preferred form for supplementation because its longer half-life ensures stable blood levels from a single daily dose. WeightWorld uses MK-7, which aligns with current best practice in supplement formulation.

EFSA-Approved Health Claims

  • Vitamin D contributes to the maintenance of normal bones
  • Vitamin D contributes to the normal function of the immune system
  • Vitamin D contributes to the maintenance of normal teeth
  • Vitamin K contributes to the maintenance of normal bones
  • Vitamin K contributes to normal blood clotting

365 Tablets — A Full Year Supply

At one tablet per day, a single bottle covers an entire year. This eliminates frequent reordering and makes it straightforward to build a consistent supplementation habit. The gluten-free formulation makes it accessible to a broader range of dietary needs.

Who This Product Is Designed For

  • Adults with limited sun exposure or who live in northern climates
  • Those focused on long-term bone density maintenance
  • Individuals seeking a combined D3 + K2 MK-7 in a single tablet
  • People who prefer a once-daily supplement with a full-year supply
  • Anyone following a gluten-free diet
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FAQ

Frequently asked questions

Vitamin D3 increases the absorption of calcium from food. Vitamin K2 (MK-7) activates proteins that direct calcium into bones and teeth, and away from soft tissues and blood vessels. The two nutrients work synergistically — D3 without K2 may raise circulating calcium without ensuring it reaches the right destination.

MK-7 has a significantly longer half-life in the body (approximately 72 hours vs 1–2 hours for MK-4), which means stable blood levels are maintained with a single daily dose. MK-7 also has higher bioavailability and is derived from natural fermentation sources.

2000IU is within the range considered safe for most healthy adults by major health authorities. The EU Tolerable Upper Intake Level for Vitamin D is 4000IU per day for adults. Individuals with specific health conditions should consult a healthcare provider before starting supplementation.

EFSA (European Food Safety Authority) reviews scientific evidence and approves health claims that are substantiated. An EFSA-approved claim means the stated benefit has been validated through a regulated scientific process, not simply marketing copy.

One bottle contains 365 tablets. At the recommended dose of one tablet per day, this is a full year's supply.

The product is gluten-free. For information on whether the tablet shell and K2 source are suitable for vegetarian or vegan diets, refer to the full ingredient list on the current product listing or WeightWorld's website.

Vitamin D3 and K2 pair well with Magnesium, which plays a role in Vitamin D metabolism. Omega-3 fatty acids are also commonly taken alongside D3. Those on anticoagulant medications (such as warfarin) should consult a doctor before taking Vitamin K2, as it affects blood clotting pathways.

Amazon's Choice is assigned based on factors including customer ratings, order volume and fulfilment performance. With over 7,400 reviews at 4.6 stars and 3,000+ monthly purchases, this product reflects sustained customer satisfaction over time.

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