Super Strength Vitamin D3 + K2 (MK-7) for Stronger Bones, Higher Strength

Vitamin D contributes to the normal function of the immune system and to the maintenance of normal bones, teeth and muscle function (authorised claims). K2 (MK-7) is included as it works alongside D3 in typical bone-health routines. Reviewers most often choose this combination for winter and general immune support.

4000iu (100µg) is our highest everyday D3 strength, chosen by customers who want strong support or have been advised a higher dose. It's within the recognised daily upper level for adults, but if you're unsure which strength suits you, we also offer lower-strength D3 options, and you can ask your GP.

Many take the higher strength through the darker months; others year-round. UK guidance suggests considering a Vitamin D supplement in autumn and winter, and taking a combined D3 + K2 tablet daily makes this easy to keep up as part of a routine.

D3 and K2 are a common pairing in bone-health routines, and having both in a single tablet means one dose covers both. This is our combined D3 4000iu + K2 (MK-7) 100mcg formula, designed for anyone who'd prefer to take them together rather than as two separate supplements.

Yes. Vitamin D contributes to normal absorption and use of calcium, and vitamin K2 helps direct calcium towards normal bones, so they work well alongside a calcium intake. Magnesium is also fine to pair. If you already take several supplements or any prescribed medicine, have a quick word with your pharmacist so your total daily amounts stay sensible and suited to you.

Vitamin D status is checked by a test rather than by how you feel, so day-to-day changes aren't a reliable guide. Ask your GP if you'd like your level checked, especially if you're taking the higher 4000iu strength or have specific health considerations.

Vitamin D contributes to the normal function of the immune system and to the maintenance of normal bones, teeth and muscle function (authorised claims). K2 (MK-7) is popularly paired with D3 in bone-health formulas like this one. Customers tell us they take this combination for general wellbeing through the year, particularly in winter.

Taken daily as directed, this supports normal immune function, muscle function and bone and teeth maintenance as part of a balanced diet. Don't exceed the stated daily dose. If you're on medication, especially anticoagulants, or have a medical condition, check with your GP or pharmacist before starting a daily D3 + K2 supplement.

This isn't suitable for everyone. Speak to your GP or pharmacist first if you're pregnant or breastfeeding, take anticoagulant medication, have a kidney condition, or take other supplements containing Vitamin D, as levels can add up. Always check the label and keep to the recommended daily amount.

Vitamin D contributes to the maintenance of normal teeth, which is an authorised claim covering this nutrient. K2 is commonly included alongside D3 in bone and teeth-focused formulas like this one. As with any supplement, it works best alongside good oral care and a varied, balanced diet.

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UK standard delivery usually takes 2, 3 working days from dispatch (excluding weekends and bank holidays). For Next Day Delivery, please place your order by 1pm Monday, Friday for delivery on the next working day. You'll receive a tracking email as soon as your order has been dispatched, so we recommend checking your tracking information first if your order hasn't yet arrived.

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We primarily serve customers in the UK, but we also deliver to selected international destinations. Please see our Shipping and Returns for the countries we currently ship to and applicable delivery charges.

We offer a 90-day hassle-free returns policy on unopened products. Return postage costs are the customer's responsibility unless the item is faulty or sent in error.

Our supplements are made in the UK in GMP-certified facilities to stringent quality standards. We carefully select our ingredients and carry out rigorous quality checks throughout the manufacturing process, so every product meets our high standards.

Every order is covered by our 90-day money-back guarantee. If you are not completely happy for any reason, contact our Customer Care team within 90 days of purchase and we will refund you, no awkward questions. It is our way of making it easy to try something new with confidence.