The UK government wants everyone to think about taking vitamin D3 and K2 supplements, especially during autumn and winter. You might wonder why. The answer lies in our limited sunlight exposure, which makes it hard to maintain healthy vitamin D levels naturally.
Vitamin D plays a crucial role in our bodies. It regulates calcium and phosphate levels that keep our bones, teeth, and muscles healthy. The best D3 and K2 combinations become even more vital when you look at the statistics. Around 95% of the US population doesn't get enough vitamin D, and UK numbers tell a similar story. Without enough vitamin D, children risk developing rickets while adults could face osteomalacia - both conditions cause bone pain and deformities.
This piece will tell you everything about vitamin D3 and K2 supplementation. You'll learn how these vitamins work together to support bone and heart health, and discover the top products you can find in the UK market today.
Understanding Vitamin D3 and K2: The Simple Facts
Vitamin D3 and K2 team up to support your bone health, immune function, and cardiovascular system. You'll better appreciate their partnership by learning how each nutrient works on its own.
What is vitamin D3 and how is it made?
Vitamin D3 (cholecalciferol) is a fat-soluble nutrient that people call the "sunshine vitamin" and with good reason too. Your body can produce vitamin D3 when your skin meets ultraviolet B (UVB) rays from sunlight40. This amazing process takes place in the lower layers of your skin's epidermis. UVB rays spark a biochemical reaction that turns a cholesterol-like substance into vitamin D341.
The original form doesn't work biologically. Your body needs to transform vitamin D3 twice before it can help you. Your liver changes it to 25-hydroxyvitamin D (calcidiol) first. Your kidneys then create the active form called 1,25-dihydroxyvitamin D or calcitriol42.
Active vitamin D serves many purposes in your body. It helps calcium absorption in your gut, keeps your blood's calcium and phosphate levels steady, and lets your bones mineralize normally42. Scientists have found vitamin D receptors in almost every type of body tissue, which suggests it plays a big role in many health aspects43.
What is vitamin K2 and where does it come from?
Vitamin K2 (menaquinone) is part of the vitamin K family, along with vitamin K1 (phylloquinone)44. These forms share a similar quinone ring structure but differ in their side chains and how they work in your body45.
K2 exists in several forms, labeled MK-4 through MK-13, based on their side chain length45. MK-4, MK-7, and MK-9 have been studied the most44. Unlike D3, sunlight can't help your body make K2. You get it from two main sources:
1. Bacterial synthesis - Bacteria create most K2 forms. This happens in fermented foods and in your gut, where good bacteria make longer-chain menaquinones (MK-5 to MK-13)45.
2. Conversion process - Your body changes some vitamin K1 from leafy greens into K2's MK-4 form. This doesn't work very well though - you only absorb 10-15% of the K1 you eat46.
You'll find K2 mostly in fermented foods like natto (Japanese fermented soybeans), some cheeses, and animal products such as organ meats and egg yolks46. Natto stands out because it has lots of MK-7, which stays in your blood longer than other forms41.
Why these vitamins matter for UK residents
UK residents need to know about these vitamins for several key reasons:
The UK's northern location and cloudy weather limit natural vitamin D production. Public Health England says everyone should think over taking vitamin D supplements throughout the year, not just in autumn and winter43. This advice recognizes how our climate affects our vitamin D levels.
These vitamins work together to keep your bones and heart healthy. D3 boosts calcium absorption from your intestines and increases osteocalcin production47. Vitamin K2 must activate osteocalcin through carboxylation before it can guide calcium into your bones47.
Not having enough K2 can cause two problems:
-
- Your bones can't properly use calcium, which makes them more likely to break
- Extra calcium might build up in your arteries instead of your bones, leading to heart problems47
This teamwork explains why the best vitamin D3 and K2 supplements combine both nutrients. Research shows using D3 and K2 together works better at preventing bone loss than using either one alone43.
Studies have also shown that taking vitamin K supplements and eating enough fiber can help keep your teeth healthy and prevent tooth loss from gum disease, especially in men46. This shows just one of many ways vitamin D3 can help you beyond bone health.
UK adults should remember these vitamins don't work alone. They're partners in a complex system that keeps your bones strong, heart healthy, and immune system working well throughout your life.
Natural Sources vs Supplements
UK residents face unique challenges to get enough vitamin D3 and K2. Natural sources exist for both nutrients, but several factors affect whether these sources alone can meet your body's needs.
Sunlight exposure in the UK
The UK's location creates a vitamin D production challenge. Most people can make enough vitamin D from sunlight from late March/early April through September5. In spite of that, between October and early March, the sun's rays aren't strong enough for your body to make adequate vitamin D through your skin5.
People with lighter skin need just 10-15 minutes of daily sun between April and September. This provides enough year-round vitamin D while keeping sunburn and skin cancer risks low48. People with darker skin need 25-40 minutes of exposure48. Professor Ann Webb, an expert in Atmospheric Radiation, says "little and often" works best for most people who want safe sun exposure48.
You need to strike a careful balance with sun exposure. Your skin should never look pink or sunburnt—either during or hours after being in the sun48.
Food sources of D3 and K2
You can boost your vitamin D3 and K2 levels through certain foods, even though natural sources are limited:
Vitamin D3 food sources:
Vitamin K2 food sources:
K2 stays active in your body much longer than K1. K1 leaves your blood within 8 hours, while K2 remains active for up to 72 hours51. On top of that, K2 helps direct calcium to your bones and keeps it from building up in arteries and organs where it could cause harm51.
Why supplements are often necessary
UK residents often need D3 and K2 supplements despite natural sources being available:
Vitamin D deficiency rates in the UK are worryingly high, especially among people with darker skin and during winter48. Professor Lesley Rhodes points out that "many people in the UK get insufficient vitamin D"48. So the NHS suggests everyone should think about taking a daily supplement with 10 micrograms of vitamin D during autumn and winter5.
These groups should take vitamin D supplements all year:
-
- People with limited outdoor time (frail or housebound individuals)
- Those living in care homes
- People who cover most skin when outdoors
- People with darker skin tones5
The Department of Health and Social Care has specific guidelines for children. Babies up to 1 year need a daily supplement with 8.5-10 micrograms of vitamin D throughout the year if they're breastfed or drink less than 500ml of infant formula daily5. Children aged 1-4 years need a daily 10-microgram supplement year-round5.
Public Health England has responded to growing concerns about low vitamin D levels. They now suggest everyone should think about taking vitamin D supplements all year, not just during autumn and winter43.
Modern lifestyles mean we don't get much sun exposure. It's also hard to get enough vitamin D from food alone. That's why many doctors now recommend high-quality supplements as the most reliable solution52.
Who Should Take Vitamin D3 and K2 Supplements?
The UK government says everyone needs vitamin D supplements during autumn and winter. Some people need these supplements more than others. Let's look at who needs the best vitamin D3 and K2 supplements UK providers have to offer. This will help you decide if you need them too.
People with limited sun exposure
Your risk of vitamin D deficiency goes up if you don't spend much time outdoors. The Department of Health and Social Care recommends daily vitamin D3 supplements throughout the year if you:
-
- Are frail or housebound
- Live in care homes or similar institutions
- Wear clothing that covers most of your skin when outdoors5
These groups don't get enough sunlight to keep their vitamin D at healthy levels. Research shows that vitamin K2 works with vitamin D3 to help your body absorb and use calcium better, which makes taking them together a smart choice9.
The UK's location and weather make it hard to get enough vitamin D naturally. This is especially true from October to March when UVB rays are too weak. You might need supplements year-round, even if you're active outdoors.
Older adults and postmenopausal women
Your body's natural ability to make and absorb vitamin D drops as you age. After 50, you'll absorb less vitamin D and your bone density will start to decline naturally. This makes supplements more important than ever53.
Postmenopausal women face special challenges that make vitamin D3 and K2 supplements essential:
Yes, vitamin D3 helps your body absorb calcium, but you need K2 to get that calcium into your bones. Research points to better health outcomes with vitamin D levels between 40-60 ng/mL (100-150 nmol/L). These levels link to lower heart disease risk and better survival rates11.
Taking these supplements early can protect postmenopausal women from losing bone density. Studies show that taking D3 and K2 together works better than using either one alone12.
People with darker skin tones
Your risk of vitamin D deficiency is higher if you have darker skin because of melanin's protective effects. The NHS recommends year-round vitamin D supplements if you have African, African-Caribbean, or South Asian background5.
Melanin makes it harder for your skin to make vitamin D from sunlight. Research shows vitamin D deficiency affects about 57.2% of people with Asian ancestry and 38.5% of those with Black African ancestry in the UK. This compares to just 17.5% of those with White European ancestry3.
Black people who stay fit are 45% less likely to lack vitamin D than those who don't exercise much. However, obesity increases vitamin D deficiency risk by 70% in Black individuals compared to those at healthy weights13.
The seasons make this worse, as Black and brown women face higher deficiency risks all year round14. Regular supplements become crucial.
Learn more about vitamin D deficiency
Vitamin D deficiency affects about 1 billion people worldwide15. Getting enough vitamins D3 and K2 from food alone is tough. Quality supplements are a practical way to maintain good levels, especially if you're in a high-risk group.
Top 8 Best Vitamin D3 and K2 Supplements in the UK
Your risk group for vitamin D deficiency determines which supplement works best for you. Let me share what we learned from researching the best vitamin D3 and K2 supplements you can buy in the UK. Each supplement offers unique benefits based on your needs.
1. Liposomal Vitamin D3&K2&C (Liposomal Vitamin D3&K2&C)
This state-of-the-art liposomal technology delivers superior absorption rates compared to traditional supplements. The advanced formula combines vitamin D3 (10mcg/400IU), K2 (45mcg), and vitamin C (500mg) in a highly bioavailable form16.
Liposomal encapsulation shields these vital nutrients from stomach acid degradation. The absorption rate can reach up to 98% - this is a big deal as it means that it works better than conventional supplements17. The pleasant-tasting liquid formula supports bone health, immune function, and skin maintenance. It's suitable for vegans too16.
2. Metagenics Vitamin D3 5000 + K2
Metagenics created a high-potency formula with 125mcg (5000IU) of vitamin D3 and 90mcg of vitamin K22. This professional-grade supplement comes recommended by functional medicine practitioners and naturopaths.
Regular users report better vitamin D blood levels. Some even improved from osteoporosis to osteopenia2. The small, orange-scented softgels make daily supplements more enjoyable than typical vitamin tablets.
3. Sports Research D3 + K2
Sports Research created a perfect plant-based formula combining VegaDELight™ Vegan D3 (125mcg/5000IU from lichen) and MenaQ7® K2 (100mcg from chickpea) in veggie softgels6. Virgin coconut oil boosts absorption of these fat-soluble vitamins.
The non-GMO, gluten-free formula strengthens bones and immune function. Finding a vegan-friendly vitamin D3 supplement isn't easy, which makes this one special6.
4. Codeage Calcium Pro+
Codeage's detailed bone health formula has calcium (250mg), vitamin D3 (12.5mcg/500IU), vitamin K2 as MK-7 (50mcg), plus magnesium, zinc, copper, and boron18. Postmenopausal women concerned about bone density will find this all-in-one approach helpful.
Each bottle lasts four months with 120 servings, making it an economical solution for long-term use19. The vegetarian-friendly capsules come from cGMP-certified facilities, guaranteeing quality and purity.
5. Innerbody Testosterone Support
This specialized formula targets hormonal balance through vitamin D3 (1000IU) and K2 (75mcg) with added nutrients20. Zinc (25mg) and selenium (20mcg) work together to support men's health.
The supplement's collaborative effort includes ashwagandha, fenugreek, maca, and longjack. These herbs traditionally boost testosterone production and overall vitality21.
6. Cytoplan D3 & K2
Cytoplan packs 100μg (4000IU) of plant-based vitamin D3 and 100μg of vitamin K2 (MK-7) in each capsule22. This potent formula helps quickly raise vitamin D levels or provides seasonal support during winter months.
The tiny capsules contain no GMOs, wheat, soy, dairy, colorings, or flavorings. They work well with various dietary priorities and sensitivities23.
7. Nutravita Vitamin D3 & K2
Nutravita blends 3000IU of vitamin D3 with 100mcg of fully bioactive, all-trans vitamin K2 MK-71. Their formula uses K2 from Kappa Bioscience, proven effective in 22 clinical trials1.
A 120-capsule bottle lasts 4 months at a reasonable price. Users notice less joint stiffness and recover faster from minor illnesses with regular use1.
8. Solgar D3 & K2
Solgar brings 70 years of supplement manufacturing expertise to this combination. Their D3 and K2 formula optimizes calcium distribution to support bone mineralization and heart health24.
The company's steadfast dedication to quality shows in their small-batch production using premium ingredients. They avoid unnecessary fillers, binders, or artificial colorings25. Healthcare professionals often recommend this gold-standard approach.
How to Read Supplement Labels
Reading supplement labels can feel overwhelming. This guide will help you understand what to look for when choosing the best vitamin d3 and k2 supplements UK stores have available. Let's break down these labels together so you can pick products that work best for you.
Understanding mcg vs IU
Supplement labels show vitamin D3 and K2 amounts in two ways: micrograms (mcg/μg) or International Units (IU). Here's what you need to know about these measurements:
Micrograms (mcg or μg) show the actual weight of a vitamin. One microgram is a millionth of a gram26. Think of it as a paper clip divided into a million tiny pieces - that's how small one microgram is!
International Units (IU) tell us how the vitamin works in your body rather than its weight27. Scientists created this system to measure vitamins' effects consistently.
The math for vitamin D is simple: 1 microgram of vitamin D equals 40 IU28. A supplement with 25 mcg of vitamin D3 gives you the same 1,000 IU you might see on older labels7.
New rules make manufacturers list both mcg and IU on labels8. This switch to metric units gives you more precise dosing and matches what health experts prefer.
What MK-4 and MK-7 mean
Labels for the best vitamin d3 and k2 supplements often show "MK-4" or "MK-7" - these are two types of vitamin K2:
MK-4 (menaquinone-4) works quickly but stays in your blood for just 4-6 hours29. You'll need to take these supplements more often to keep steady levels.
MK-7 (menaquinone-7) lasts much longer in your body - up to 72 hours30. You won't need as many doses to maintain good levels, which makes daily use easier.
Product labels might say "Vitamin K2 (as menaquinone-7)" or "Vitamin K2 (MK-7)" with the amount31. Top-quality supplements often use special forms like MenaQ7®, a tested MK-7 made from chickpea protein without common allergens9.
Both types help your bones and heart by moving calcium where it needs to go. Your choice might depend on how often you want to take supplements.
Checking for allergens and additives
Labels tell you more than just vitamin content. They list other ingredients that could affect your health:
Allergen disclosure must list major food allergens like milk, eggs, fish, shellfish, tree nuts, soy, wheat, and peanuts26. You might see "Contains Soya" right in the ingredients30.
Claims like "free from all allergens" don't have FDA oversight, so be careful if you have serious allergies26. Some brands go further by stating "This product is hypoallergenic / does not contain any of the 14 major allergens"9.
Additives and fillers appear at the end of ingredient lists and include:
-
- Bulking agents (Di-Calcium Phosphate, Microcrystalline Cellulose)
- Anti-caking agents (Magnesium Stearate)
- Preservatives (potassium sorbate)
- Flavor enhancers (peppermint oil)
Ingredients appear by amount - the most abundant comes first26. Products with shorter ingredient lists or "clean label" marketing usually have fewer additives.
Keep in mind that "natural" supplements can contain additives too. Reading labels carefully helps you find products that match your health goals and dietary needs.
Visit our guide to recognizing quality vitamin supplements to learn more about choosing the best products.
Safety, Dosage, and Side Effects
Taking the best vitamin D3 and K2 supplements UK retailers offer can improve your health. You need to know the right dosage and risks to supplement safely.
Safe upper limits for adults and children
The NHS recommends 10 micrograms (400 IU) of vitamin D daily for most adults during autumn and winter months. Adults, including pregnant and breastfeeding women, should not exceed 100 micrograms (4,000 IU) per day. Going over this limit could harm your health.
Children need different amounts based on their age:
-
- Infants under 12 months: Maximum 25 micrograms (1,000 IU) daily
- Children aged 1-10 years: Maximum 50 micrograms (2,000 IU) daily
- Adolescents 11-17 years: Maximum 100 micrograms (4,000 IU) daily
The NHS states vitamin K2's safe upper limit is about 1 mg (1,000 μg) daily.
Potential side effects of high doses
High doses of vitamin D3 supplements can lead to hypercalcemia—excess calcium buildup in your body. This condition weakens bones and might damage your kidneys and heart tissue.
Watch out for these vitamin D toxicity symptoms:
-
- Nausea and vomiting
- Loss of appetite and weight loss
- Muscle weakness
- Confusion and difficulty thinking clearly
- Heart rhythm irregularities
- Kidney stones and kidney damage
- Excessive thirst and urination
You can't overdose on vitamin D through sunlight or food alone. Only supplement overuse causes toxicity.
When to avoid supplementation
Some health conditions require extra care with vitamin D3 and K2 supplements:
People with hypercalcemia should stay away from vitamin D3 since it boosts calcium absorption and could make things worse.
Kidney disorder patients need to be careful with vitamin D3 as it might worsen their condition.
Some medications don't mix well with these supplements:
-
- Blood thinners (warfarin) can clash with vitamin K2
- Digoxin (heart medication) mixed with vitamin D3 might cause dangerous heart rhythms
- Some cholesterol-lowering drugs may not work well with these supplements
Patients with sarcoidosis or other granulomatous diseases should only take vitamin D3 under a doctor's close supervision. These conditions can increase your body's natural vitamin D production.
NHS guidance on vitamin D
The NHS guidance on vitamin D provides detailed information about vitamin D supplementation.
Talk to your healthcare provider before starting supplements, especially if you have health conditions or take prescription medications.
Buying Tips and Trusted Brands
Knowing how to spot quality supplements makes all the difference when you're faced with endless choices. Several factors determine if vitamin D3 and K2 supplements will work and remain safe.
What to look for in a quality supplement
The supplement form should be your first concern. Research shows that oil-based formulations give D3 better absorption [link_1] because D3 is fat-soluble32. Softgels or liquid capsules beat tablets in terms of bioavailability4.
Quality supplement labels should show these ingredients:
-
- Cholecalciferol (D3) rather than ergocalciferol (D2)
- MK-7 form of K2 to last longer in your system
- Clean ingredients without unnecessary fillers or preservatives4
Manufacturing standards play a huge role. Most supplements follow food-grade standards that allow 80-150% of labeled potency. Pharmaceutical-grade products maintain stricter limits (95-105% of labeled amounts)32. This precision will give a consistent dose and reliable results.
Third-party testing and certifications
Quality testing evidence matters just as much. Independent verification from third-party labs proves that supplements match their label claims33. These tests also screen for contaminants that might sneak in during manufacturing4.
Look for these trustworthy certifications:
Customer reviews are a great way to get ground feedback about how well supplements work4. Products from companies that are several years old with science-based formulas usually outperform generic alternatives.
A newer study, published by researchers, showed big differences between label claims and actual content in many vitamin D and K supplements35. So third-party testing becomes crucial to ensure you get the nutrients you pay for.
Shop premium D3/K2 supplements
Premium D3 and K2 combinations that meet these strict standards give you peace of mind through verified purity and potency.
Vitamin D3 and K2 in Special Populations
Different groups of people need specific approaches to supplementation. The UK market offers several best vitamin d3 and k2 supplements UK options that various groups can use safely based on their unique nutritional needs.
Pregnant and breastfeeding women
Pregnancy and breastfeeding create higher nutritional needs. The UK National Health Service recommends a daily intake of 10 micrograms (400 IU) of vitamin D throughout the year for pregnant and breastfeeding women36. This helps protect the mother's teeth and muscles while ensuring babies grow strong bones and teeth.
Vitamin K2 safety during pregnancy remains unclear. Healthcare providers should be consulted before starting any supplementation37. Breastfeeding mothers can take vitamin K2 without special precautions.
Children and infants
Babies and children need specific amounts of vitamin D. The Department of Health and Social Care recommends these guidelines:
Children between 1-4 years need 10 micrograms of vitamin D year-round5. Research shows 45-50 mcg/day of vitamin K2 works well for children38.
Healthcare providers might prescribe higher vitamin D doses temporarily to treat deficiency:
People with chronic illnesses
Health conditions can affect how supplements work in the body. People with fat malabsorption disorders often lack vitamin D and K238.
Kids with cystic fibrosis show vitamin K deficiency even when taking recommended supplements38. Young patients with inflammatory bowel disease, especially those with Crohn's Disease, also tend to lack vitamin K38.
Patients who have chronic kidney disease without renal failure can benefit from combined supplements. Studies show daily doses of vitamin D3 (400-800 IU) and K2 (37-100mg) help normalize vitamin D levels and improve bone health markers10.
NICE guidance on vitamin D and COVID-19
The National Institute for Health and Care Excellence (NICE) offers complete guidance about vitamin D supplementation during the COVID-19 pandemic.
Conclusion
Vitamin D3 and K2 supplementation is a vital health practice for UK residents throughout the year, not just during darker winter months. This piece has shown how these powerful nutrients work together to direct calcium into bones and prevent harmful arterial deposits. Natural sources exist, but the UK's northern latitude and cloudy weather substantially limit vitamin D production. Most people need supplements to maintain healthy levels.
Several groups have higher deficiency risks. People with limited sun exposure, older adults, postmenopausal women, and those with darker skin tones need daily supplements even more. A careful look at product labels helps you pick supplements with the right forms and dosages without unnecessary additives or allergens.
Safety should be your top priority when taking vitamins D3 and K2. Adults should stay within 100 microgram (4,000 IU) daily upper limit for vitamin D3. Children need lower doses based on their age. Of course, you should talk to your healthcare provider before starting supplements to avoid medication interactions or health complications.
Goldman Laboratories' Liposomal Vitamin D Complex stands out among supplement options. Its superior absorption technology and detailed formulation make it an excellent choice if you want optimal vitamin D and K2 benefits.
Research strongly supports vitamin D3 and K2 supplementation for UK residents. These nutrients protect your bones, boost immune function, and help your heart - benefits that matter more as you age. Individual needs vary, but most UK adults should take supplements year-round, especially during autumn and winter when natural vitamin D levels drop. Finding the right supplement is a simple yet powerful way to invest in your long-term health and wellbeing.
FAQs
Q1. What are the best vitamin D3 and K2 supplements available in the UK? Some top options include NOW Foods Vitamin D-3 & K-2, Innerbody Testosterone Support, Codeage Calcium Pro+, and Metagenics Vitamin D3 5000 + K2. The best choice depends on your specific needs and health goals.
Q2. Is it safe to take vitamin D3 and K2 supplements together? Yes, it's generally safe and often recommended to take vitamin D3 and K2 together. These vitamins work synergistically - D3 helps with calcium absorption, while K2 directs calcium to the bones and away from arteries.
Q3. Who should consider taking vitamin D3 and K2 supplements in the UK? Most UK residents should consider supplementation, especially during autumn and winter. Those at higher risk of deficiency include people with limited sun exposure, older adults, postmenopausal women, and individuals with darker skin tones.
Q4. What should I look for when choosing a vitamin D3 and K2 supplement? Look for supplements containing cholecalciferol (D3) and the MK-7 form of K2. Choose products with clean ingredients, third-party testing certifications, and appropriate dosages. Oil-based formulations or softgels typically offer better absorption.
Q5. Are there any side effects or risks associated with vitamin D3 and K2 supplementation? While generally safe, excessive vitamin D3 intake can lead to hypercalcemia. It's important to stay within recommended dosages, typically not exceeding 100 micrograms (4,000 IU) daily for adults. Always consult a healthcare provider before starting any new supplement regimen, especially if you have existing health conditions or take medications.
References
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[2] - https://www.metagenics.com/en-us/product/vitamin-d3-5000-k?srsltid=AfmBOophVBVjXMXOaZBC9CKhdF6hlECT7nPNDS28oejsse9iSvlArXE5
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[44] - https://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/
[45] - https://en.wikipedia.org/wiki/Vitamin_K2
[46] - https://www.healthline.com/nutrition/vitamin-k2
[47] - https://www.nutriadvanced.co.uk/news/ingredient-focus-vitamin-d3-and-k2/
[48] - https://www.britishskinfoundation.org.uk/sunlight-and-vitamin-d
[49] - https://health.clevelandclinic.org/vitamin-k2-foods
[50] - https://www.vitalnutrients.co/blogs/education/nourish-your-body-with-vitamin-d3-and-vitamin-k2-food-and-sunlight-sources?srsltid=AfmBOopf76R8IV4OpoBpMB7awGEueX9v2x3iuQhfX8b4_v8CuLXXHSMc
[51] - https://www.bbc.co.uk/news/magazine-24049950
[52] - https://www.webmd.com/diet/foods-high-in-vitamin-d3
[53] - https://www.sunvitd3.co.uk/blogs/news/benefits-of-vitamin-d-and-k2?srsltid=AfmBOooNst91ujgl78eybcjrrJslCYd4xnL2phOWFxml7C7BnMVSIeQn
