Thorne Vitamin D/K2 Liquid Review

Vitamin D + K2 Liquid from Thorne is presented as a convenient combination of vitamin D and vitamin K for bone, cardiovascular, and immune support. The page states that the product promotes bone health, healthy immune function, and cardiovascular health, and that the combination of vitamin D3 and K2 provides greater benefits together than either does individually. The details section explains that vitamin D3 and K2 work together to benefit bone health, cardiovascular support, and healthy immune function. Maintaining an optimal level of vitamin D throughout all stages of life is described as helping maintain strong bones and healthy immune function. Adding vitamin K2 is described as helping move calcium to the bones to protect soft tissues, such as the arteries and kidneys, from calcification. The listed benefits include supporting a healthy heart and blood circulation, promoting bone health and calcium absorption, benefiting immune function, and providing advanced bone health support. The listed features include that the vitamin K2 in this formula is MK-4, described as the most clinically studied form of vitamin K; that vitamin D in its D3 form is described as more potent and better absorbed than its D2 form; that the self-dispensing top provides an accurate, safe, and individualized dose by metering individual drops; and that the liquid is in medium chain triglyceride oil and preserved with mixed tocopherols. The page says the product has been third-party tested and certified to verify that what is in the package matches the label and to confirm it contains no unsafe levels of contaminants such as heavy metals, pesticides, and microorganisms. Serving size is listed as 2 drops with 600 servings per container, and the price is listed as $34 for 1200 drops. A subscription option lists $30.60 with a 10 percent discount. Warnings state that the product is contraindicated in individuals with a history of hypersensitivity to its ingredients, that pregnant individuals should consult a health-care practitioner, that vitamin K can interfere with a med drugs such as a med, and that the product is not intended for children under 12 months. The FAQ section says the formula is ideal for those wanting to support bone, cardiovascular, and immune health, and recommends testing vitamin D levels before supplementation. It also explains that Thorne tests each ingredient for identity, purity, and potency, and that vitamin D3 is generally considered the preferred form because it is more effective at raising and maintaining vitamin D levels in the blood than D2. The FAQ further describes vitamin D and K2 as working together, with vitamin D enhancing calcium absorption and retention and vitamin K2 helping direct calcium into bones and teeth and away from soft tissues. Individuals taking meds are advised to consult a health-care professional before using vitamin K supplements.

Product Focus: Bone Health
Tier ⓘ
Tier 2 · Rank 4
Tier 2 · Researched. Human studies show improvement in an aging-related function or a specific goal, and the reviews agree. Rank 4 within Tier 2 for Bone Health; 4 of 79 overall. Tiers run from 1, the strongest evidence, to 5. How we grade →
Evidence ⓘ
82 /100
How strongly the evidence says this product works: human studies count most, then real reviews, then our biohacker panel.
Positive Reviews
80% of 7,180
Biohacker Mentions
9 of 10
Cost per month
$2

Study, Trial or Testing Result Summary

Members Only85 human studies · 42 improved
85 human studies42 improved16 no effect193,963 people studied

Both ingredients in this liquid are at or above the doses used in studies. Vitamin K2, at 200 micrograms here, has the stronger support for bone health. Pooled analyses of postmenopausal women with thinning bones found it raised spine bone density more than control, with no serious side effects [1][2]. The spine benefit showed up in women with thinning bones but not in those without, and fewer fractures appeared only after one study was left out [3]. In healthy postmenopausal women, 180 micrograms a day for three years slowed bone loss at the spine and hip neck [4]. A one-year trial found 90 micrograms a day reduced hip bone loss in postmenopausal women but not in men [5]. Vitamin D, at 25 micrograms here, gives mixed results. One review found 700 to 800 units a day cut hip fractures by 26%, while 400 units did not help [6]. Other reviews found no clear drop in fractures [7][8]. A large review of women with thinning bones found calcium plus vitamin D slightly improved pelvic bone density but did not reduce fractures [9]. Animal and cell studies are never counted.

See all 85 studies →Hide the studies

Review Totals and Summary

Members Only7,180 reviews · 80% positive
7,180 reviews · Amazon 6,832 · Walmart 348
80% positive6% neutral14% negative

This Thorne Vitamin D/K2 Liquid has garnered about 7180 ratings across various stores, presenting a mixed but generally positive picture for potential buyers. Many customers praise its effectiveness and the convenience of its liquid form, though a significant number express frustration with its dispensing mechanism. **What it did for them** Many users report positive health impacts from taking this supplement. Some notice a difference quickly, with one user stating they "Can feel the difference almost immediately." Others experience increased energy, with a reviewer noting, "I am finding that I have more energy which is the biggest benefit." For some, it's the only D3 supplement they can tolerate, avoiding issues like hot flashes experienced with other products. Reviewers who trust the Thorne brand and are vitamin D deficient often plan to continue using it, citing its perceived effectiveness and bioavailability. **Form and Ease of Use** The liquid form is a major draw, especially for those who "can't swallow pills." Many find it "so easy to take" and appreciate that it is "completely flavorless as near as I can tell." This neutrality allows it to mix smoothly into food and drink, making it effortless to integrate into a daily routine. This aspect is frequently highlighted as a key benefit, particularly for individuals who struggle with traditional pill supplements. **Dispenser Complaints** The most common and significant complaint revolves around the bottle's dispensing system. Many find it "Hard to dispense," with drops coming out very slowly, or not at all, making it feel "like an eternity for even one drop to come out." Users report difficulty seeing how many drops are dispensed, leading to uncertainty about correct dosage. Some describe it as the "most frustrating vitamin delivery system ever," with drops splattering onto faces or clothes, rather than reliably reaching the mouth. Several reviewers suggest a standard squeeze dropper would be a much better alternative, expressing frustration that the company's design team hasn't addressed this. Occasional packaging issues, such as broken seals and leakage, were also mentioned, though one buyer considered it "not a big deal." **Value for Money** One reviewer explicitly mentioned the product as "cost effective," suggesting that some users perceive it as a good value given its benefits and form. **Who it suits and who it did not** This liquid supplement seems well-suited for individuals who struggle with swallowing pills or have experienced adverse reactions like hot flashes with other D3 supplements. It appeals to those seeking an easy-to-integrate, flavorless option for their daily routine. However, it may not suit those who require precise dosing or who are easily frustrated by difficult-to-use dispensers. Many users, despite acknowledging the product's benefits, state they "will not repurchase" due to the dispenser issues, while others are willing to tolerate the frustration for the perceived benefits.

Biohacker Summary

Members Only9 of 10 recommend it
9 of 10 biohackers on our panel recommend it

The panel leans toward vitamin D, which is not a minor ingredient here in the panel's discussion but is listed as a smaller ingredient in this product, and it drew comments from all ten of them. Four of them said they take it themselves, and three of those take 5,000 IU of D3 in the morning, while one has taken D3 with K2 for over a decade. They give reasons such as immune support, brain and mood, muscle, sperm health, and low sun exposure, and one suggested checking blood levels first. One said to take at least 10,000 IU a day, another said it only helps most people if they are deficient, and one said the standard 600 IU recommendation leaves many people short. Vitamin K2 is also a smaller ingredient in this product; several on the panel recommend it with vitamin D for bone health and calcium handling, and two take 90 to 100 mcg in the morning.

See all 10 biohackers →Hide the biohackers
  • Dr. Eric Berg · Vitamin D · neutral
    • 8 Nov 2026 · neutral · Facebook ↗
      Lists Vitamin D as an ingredient found in sardines.
    • 7 Nov 2026 · recommends · Facebook ↗
      Recommends Vitamin D3 because it's nearly impossible to get enough from food and most people don't get enough sun, advising to aim for blood levels of at least 50 to 80 ng/mL.
    • 7 Nov 2026 · neutral · Instagram ↗
      Dr. Berg states that when nutrients like vitamin D are too low, fatigue and weakness can follow.
    • 7 Nov 2026 · Vitamin K · recommends · Facebook ↗
      Recommends pairing Vitamin D3 with K2, stating that K2 helps keep calcium out of soft tissues.
    • 6 Nov 2026 · recommends · Podcast ↗
      Recommends focusing on vitamin D3 to support stronger bones if a neck hump is associated with osteoporosis.
    • 6 Nov 2026 · recommends · YouTube ↗
      Recommends a minimum of 10,000 IU of vitamin D per day to support natural killer cells.
    • 6 Nov 2026 · Vitamin K · recommends · Podcast ↗
      Recommends focusing on vitamin K2 to support stronger bones if a neck hump is associated with osteoporosis.
    • 5 Nov 2026 · recommends · Podcast ↗
      Suggests that increasing vitamin D3 may help address the underlying problem of bruxism.
    • 2 Nov 2026 · warns · Facebook ↗
      Dr. Berg warns that the recommended daily intake for vitamin D is based on a massive error and that the actual necessary amount is closer to 8,895 IU, with millions remaining deficient.
    • 1 Nov 2026 · neutral · YouTube ↗
      States that magnesium is needed to absorb vitamin D.
    • 31 Oct 2026 · recommends · YouTube ↗
      Recommends getting vitamin D levels tested to ensure they are between 50 and 70, as vitamin D is intimately involved in regulating prostate size.
    • 31 Oct 2026 · Vitamin K · recommends · Podcast ↗
      Discusses foods that contain Vitamin K2.
    • 30 Oct 2026 · recommends · YouTube ↗
      Recommends taking at least 10,000 IUs of vitamin D3 every single day in the winter, stating it is the most important vitamin to lower cancer risk.
    • 29 Oct 2026 · Vitamin K · recommends · YouTube ↗
      States that vitamin K2 is a key nutrient for teeth, as its primary job is to push calcium into bones and teeth, and recommends a supplement dose of 1 to 200 micrograms per day, paired with vitamin D.
  • Dr. Rhonda Patrick · Vitamin D · neutral
    • 8 Nov 2026 · neutral · Instagram ↗
      Notes that vitamin D from sunlight, food, or supplements needs to undergo conversions in the liver and kidneys to become its active hormone form, calcitriol.
    • 4 Nov 2026 · neutral · Instagram ↗
      States that Vitamin D supplementation has been associated with a 40% lower dementia risk, and low levels are linked to a 50 to 80% higher risk.
    • 1 Nov 2026 · Vitamin K · neutral · YouTube ↗
      Mentions vitamin K as one of the micronutrients found in multivitamins that people often don't get enough of from their diets.
    • 28 Oct 2026 · recommends · YouTube ↗
      Recommends getting adequate vitamin D, noting that people taking vitamin D supplements have a 40% lower risk of dementia, while those with lower vitamin D have a 50-80% higher risk.
    • 5 Oct 2026 · neutral · Facebook ↗
      Vitamin D supplementation was linked to a 40% lower risk of dementia in an observational study of more than 12,000 older adults.
    • 30 Sep 2026 · recommends · YouTube ↗
      Mentions that vitamin D also plays a role in maintaining muscle mass.
    • 28 Sep 2026 · recommends · YouTube ↗
      Recommends ensuring adequate vitamin D intake for men's sperm health.
    • 24 Sep 2026 · neutral · Facebook ↗
      Vitamin D and strength training alone did not, but adding them strengthened the effect on one clock, with the full combination slowing that measure by ~3.8 months.
    • 25 Aug 2026 · neutral · Facebook ↗
      Lutein and zeaxanthin can also be obtained from certain multivitamins.
    • 25 Aug 2026 · Vitamin K · neutral · Facebook ↗
      Lutein and zeaxanthin can also be obtained from certain multivitamins.
    • 28 Jul 2026 · recommends · Facebook ↗
      Recommends Vitamin D, noting it regulates over 5% of the genome, including genes involved in immune defense, neurotransmitter synthesis, and longevity, and correcting deficiency may slow epigenetic aging.
    • 22 Jul 2026 · neutral · YouTube ↗
      Uses Vitamin D3 as an example of a supplement that an AI model could track to see its impact on other metrics like glucose levels.
    • 29 Jun 2026 · Vitamin K · neutral · Facebook ↗
      Mentions that kale delivers vitamin K, a micronutrient many diets fall short on.
    • 15 May 2026 · Vitamin K · uses · Instagram ↗
      Rhonda takes 100 mcg of Vitamin K2 (MK-7) daily for general health.
  • Dave Asprey · Vitamin K · recommends
    • 7 Nov 2026 · recommends · YouTube ↗
      Explains that Vitamin K2 acts as a traffic cop for calcium, waving it into bones and away from arteries, and that grass-fed butter is one of the only foods with a real amount of K2.
    • 1 Nov 2026 · Vitamin D · uses · Facebook ↗
      Takes Vitamin DAKE from Suppgrade Labs.
    • 25 Oct 2026 · Vitamin D · recommends · Podcast ↗
      Suggests that vitamin D supports brain health, muscle function, and focus.
    • 9 Oct 2026 · Vitamin D · recommends · Podcast ↗
      Host Dave Asprey explains why correcting a vitamin D deficiency still makes sense for male fertility, even though supplementation did not improve overall semen parameters in a randomized trial.
    • 7 Oct 2026 · recommends · YouTube ↗
      Recommends taking vitamin K2 with vitamin D to keep calcium in the bones, and suggests kids also take it for stronger bones.
    • 7 Oct 2026 · recommends · YouTube ↗
      Recommends Vitamin K2, stating it supports healthy calcium metabolism.
    • 7 Oct 2026 · Vitamin D · uses · YouTube ↗
      States that currently, he is only taking vitamin C and vitamin D.
    • 5 Sep 2026 · recommends · YouTube ↗
      Recommends adding vitamin K2 to vitamin D supplementation.
    • 5 Sep 2026 · Vitamin D · recommends · YouTube ↗
      Recommends vitamin D, noting it's actually a hormone and that most people are deficient, even those who take it, because they don't take enough.
    • 3 Sep 2026 · Vitamin D · recommends · YouTube ↗
      States that most people on the spectrum are low in vitamin D and need more of it, mentioning his own product, Vitam DAKNE, which contains real vitamin A.
    • 29 Aug 2026 · Vitamin D · recommends · YouTube ↗
      Dave Asprey recommends Vitamin D3 with K2, explaining D3 is a hormone made from sunlight and K2 directs calcium into bones, not arteries, highlighting its low cost, widespread deficiency, and the ability to test its effectiveness.
    • 18 Aug 2026 · neutral · YouTube ↗
      Mentions that natto is a good source of vitamin K2, which is probably its primary benefit.
    • 18 Aug 2026 · Vitamin D · recommends · YouTube ↗
      Recommends Vitamin D as one of the most important supplements for overall health.
    • 12 Aug 2026 · Vitamin D · uses · Facebook ↗
      Takes Vitamin DAKE from Suppgrade Labs because D3, A, K2, and E work together.
  • Thomas DeLauer · Vitamin K · recommends
    • 5 Nov 2026 · recommends · YouTube ↗
      Recommends taking Vitamin K2 with Vitamin D3 in the morning, along with morning fats, to ensure calcium is directed to the bones and not deposited in arteries or soft tissue.
    • 5 Nov 2026 · Vitamin D · recommends · YouTube ↗
      Recommends taking Vitamin D3 in the morning, between 6:00 and 10:00 a.m., to align with the body's natural metabolic activation phase and sunlight-triggered vitamin D production.
    • 23 Oct 2026 · Vitamin D · uses · YouTube ↗
      Uses vitamin D3 in the fall and winter months when getting less sun, as it's important to supplement it then.
    • 20 Oct 2026 · Vitamin D · recommends · YouTube ↗
      Recommends taking a massive amount of vitamin D simultaneously with an early morning massive breakfast to help reset circadian rhythms and address hyperphagia.
    • 8 Oct 2026 · Vitamin D · recommends · Facebook ↗
      Recommends Vitamin D, stating that it has receptors throughout the brain and deficiency can quickly impact brain and mood.
    • 6 Oct 2026 · Vitamin D · uses · YouTube ↗
      Takes supplemental vitamin D because he is skin sensitive and from northern latitudes, limiting his UV exposure.
    • 5 Oct 2026 · Vitamin D · recommends · YouTube ↗
      Recommends taking vitamin D on non-liver days to ensure both nutrients get proper receptor access.
    • 29 Sep 2026 · Vitamin D · uses · YouTube ↗
      Takes Purity's liquid vitamin D3 with K2 because she is constantly inside during the day; D3 is for overall wellness and K2 helps the body absorb calcium properly.
    • 11 Sep 2026 · Vitamin D · recommends · YouTube ↗
      Recommends getting vitamin D, suggesting it can be obtained while walking.
    • 6 Sep 2026 · Vitamin D · recommends · Instagram ↗
      States that vitamin D is best obtained from the sun, but getting it from food definitely helps, and notes its role as a hormone influencing many cells.
    • 1 Sep 2026 · Vitamin D · recommends · Instagram ↗
      Recommends D3, suggesting a dose of 2000-4000 IU, and notes that MK-7 slowed bone loss over three years.
    • 29 Jul 2026 · recommends · YouTube ↗
      Recommends using a multivitamin to ensure adequate micronutrient intake, especially when wholesome food is less available.
    • 23 Jul 2026 · recommends · YouTube ↗
      Notes that grass-fed butter provides more Vitamin K2, which plays a role in directing calcium towards bones instead of arteries, contributing to bone health.
    • 9 Jul 2026 · warns · YouTube ↗
      Advises checking multivitamins because many contain 100, 200, or 300% of the daily value of selenium, which can contribute to excessive intake.
  • Dr. Mark Hyman · Vitamin D · uses
    • 4 Nov 2026 · uses · YouTube ↗
      Consumes Zetopia's Atlantic salmon to get Vitamin D, particularly in the winter months, as it is one of the few foods that provides both Omega-3s and Vitamin D.
    • 29 Oct 2026 · neutral · YouTube ↗
      Mentions that the body makes vitamin D from sunlight exposure, and a deficiency can hinder calcium absorption, which is crucial for strong bones.
    • 26 Oct 2026 · recommends · Facebook ↗
      Recommends Vitamin D for health, stating that amazing things happen when patients' vitamin D statuses reach optimal levels.
    • 21 Oct 2026 · neutral · YouTube ↗
      Mentions vitamin D as an existing biomarker that plays a role in mental health, which Function Health includes in their measurements.
    • 19 Oct 2026 · neutral · YouTube ↗
      Notes that vitamin D plays a role in immune function.
    • 8 Oct 2026 · recommends · Instagram ↗
      Recommends checking vitamin D levels and states that if they had to pick one single intervention for immune health, vitamin D would be it.
    • 7 Oct 2026 · neutral · Podcast ↗
      Dr. Hyman discusses vitamin D in relation to sun exposure patterns.
    • 7 Oct 2026 · recommends · YouTube ↗
      States that vitamin D supplementation can help with oxidative stress.
    • 5 Oct 2026 · neutral · Podcast ↗
      Mentions vitamin D as a key nutrient for supporting immune function.
    • 5 Oct 2026 · recommends · YouTube ↗
      States that vitamin D is probably the single most important intervention for immune health, recommending levels of 45 to 70 and emphasizing testing to determine the right dose.
    • 7 Aug 2026 · Vitamin K · uses · X ↗
      Takes 100 mcg of Vitamin K2 in the morning for general health.
    • 20 Jul 2026 · Vitamin K · uses · X ↗
      Takes 100 mcg of Vitamin K2 in the morning.
    • 24 Jun 2026 · Vitamin K · uses · X ↗
      Takes 90 mcg of Vitamin K2 in the morning for overall health.
    • 17 Jun 2026 · Vitamin K · neutral · YouTube ↗
      States that green leafy vegetables are great sources of vitamin K.
  • Siim Land · Vitamin D · recommends
    • 31 Oct 2026 · recommends · YouTube ↗
      Advises against taking vitamin D in the morning with other supplements because it is fat soluble and requires dietary fat for better absorption.
    • 29 Oct 2026 · recommends · Instagram ↗
      Recommends taking Vitamin D with fat for better absorption.
    • 24 Oct 2026 · neutral · Instagram ↗
      States that Vitamin D connects biology to light and that UVB reaching the skin enables its production.
    • 9 Oct 2026 · Vitamin K · neutral · Instagram ↗
      Notes that Vitamin K2 helps activate proteins involved in bone mineralization and calcium regulation.
    • 8 Oct 2026 · Vitamin K · neutral · YouTube ↗
      Mentions that prunes contain vitamin K, which is a factor in their ability to help with bone density.
    • 7 Oct 2026 · Vitamin K · recommends · Instagram ↗
      Recommends Vitamin K2 for bone health and calcium metabolism, based primarily on human research, especially randomized controlled trials showing measurable benefits.
    • 6 Oct 2026 · Vitamin K · neutral · X ↗
      Lists Vitamin K2 as one of 15 supplements backed by human studies.
    • 30 Sep 2026 · Vitamin K · neutral · X ↗
      Lists leafy greens as a source of Vitamin K1.
    • 6 Sep 2026 · recommends · Instagram ↗
      Thinks vitamin D has some of the strongest evidence and is worth considering.
    • 6 Sep 2026 · neutral · X ↗
      Notes that Vitamin K2 pairs well with vitamin D by regulating calcium and bone mineralization.
    • 6 Sep 2026 · Vitamin K · recommends · Instagram ↗
      Thinks vitamin K2 has some of the strongest evidence and is worth considering.
    • 6 Sep 2026 · Vitamin K · neutral · X ↗
      Notes that Vitamin K2 pairs well with vitamin D by regulating calcium and bone mineralization.
    • 26 Aug 2026 · recommends · Instagram ↗
      Recommends taking vitamin D supplements with some fat to maximize its absorption, suggesting with food or a teaspoon of olive oil.
    • 23 Aug 2026 · neutral · X ↗
      Notes that taking vitamin D3 with a fat-containing meal resulted in 32% higher peak blood vitamin D levels.
  • Ben Greenfield · Vitamin D · recommends
    • 29 Oct 2026 · recommends · YouTube ↗
      Notes that Vitamin D is actually a hormone and recommends patients aim for levels around 40 to 50, or even 60 for fracture healing, for optimal healing, as opposed to just above 20 which is considered normal.
    • 15 Oct 2026 · recommends · Podcast ↗
      Mentions vitamin D as part of a bare-minimum protocol.
    • 15 Oct 2026 · recommends · YouTube ↗
      Advises getting vitamin D levels between 60 and 100 nanograms per milliliter as a minimum step for overall health and to slow down heart disease.
    • 15 Oct 2026 · Vitamin K · neutral · Facebook ↗
      Discusses vitamin K2, specifically the menaquinone forms, as crucial for arterial health and notes that it breaks down into MK-4 and MK-7.
    • 15 Oct 2026 · Vitamin K · uses · YouTube ↗
      Explains that gut bacteria liberate K from the diet or make the K needed, and that poor absorption of vitamin K due to bacterial imbalances is linked to heart disease.
    • 20 Aug 2026 · uses · YouTube ↗
      Has been taking Vitamin D3 K2 for over a decade.
    • 8 Aug 2026 · neutral · Instagram ↗
      Notes that sunlight influences more than just vitamin D production.
    • 8 Aug 2026 · recommends · YouTube ↗
      Recommends keeping vitamin D levels high, suggesting that a supplement is probably not a bad idea, especially given that many people are deficient due to spending most of their time indoors.
    • 8 Aug 2026 · Vitamin K · recommends · YouTube ↗
      Recommends taking vitamin K complex as a co-factor to increase vitamin D absorption.
    • 18 Jul 2026 · recommends · YouTube ↗
      Recommends getting enough vitamin D for blood pressure management.
    • 9 Jul 2026 · recommends · YouTube ↗
      Recommends optimizing vitamin D levels to a serum score of around 50 to 80 nanograms per milliliter, as deficiency is linked to tinnitus volume and can assist with it.
    • 7 Jun 2026 · recommends · Facebook ↗
      Recommends using hormone building blocks like vitamin D for hormone optimization.
    • 6 May 2026 · neutral · X ↗
      Notes that vitamin D deficiency is the most common deficiency.
    • 23 Apr 2026 · Vitamin K · recommends · YouTube ↗
      Lists vitamin D3 and K2 for the immune system as a recommended intervention on the True Age test.
  • Bryan Johnson · Vitamin K · uses
    • 22 Oct 2026 · uses · X ↗
      Takes 90 mcg of Vitamin K2 in the morning for general health.
    • 22 Oct 2026 · Vitamin D · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning for general health.
    • 15 Aug 2026 · Vitamin D · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning for general health.
    • 3 Jul 2026 · Vitamin D · neutral · X ↗
      Mentions that the sunlight assessment claims low vitamin D levels cause the immune system to misfire, and notes that their vitamin D has been measured.
    • 4 May 2026 · uses · X ↗
      Takes 100 mcg of Vitamin K2 in the morning for longevity.
    • 4 May 2026 · Vitamin D · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning for longevity.
    • 2 May 2026 · uses · X ↗
      He takes 100 mcg of Vitamin K2 in the morning for general health.
    • 2 May 2026 · Vitamin D · uses · X ↗
      He takes 5000 IU of Vitamin D3 in the morning for general health.
    • 21 Apr 2026 · Vitamin D · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning for general health.
    • 15 Apr 2026 · uses · X ↗
      Takes 100 mcg of Vitamin K2 in the morning for longevity.
    • 15 Apr 2026 · Vitamin D · uses · X ↗
      Takes 5,000 IU of Vitamin D3 in the morning for longevity.
    • 14 Apr 2026 · uses · X ↗
      Takes 90 mcg of Vitamin K2 in the morning.
    • 14 Apr 2026 · Vitamin D · uses · X ↗
      Takes 5,000 IU of Vitamin D3 in the morning.
    • 8 Apr 2026 · uses · X ↗
      Takes 100 mcg of Vitamin K2 in the morning.
  • Andrew Huberman · Vitamin D · neutral
    • 21 Sep 2026 · neutral · YouTube ↗
      Notes that most people are probably deficient in vitamin D and benefit from supplementing, but there's no point in doing it unless you're deficient for most things.
    • 7 Aug 2026 · uses · X ↗
      Takes 5,000 IU of Vitamin D3 in the morning for longevity.
    • 7 Aug 2026 · Vitamin K · uses · X ↗
      Takes 90 mcg of Vitamin K2 in the morning for longevity.
    • 20 Jul 2026 · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning for general health.
    • 20 Jul 2026 · recommends · YouTube ↗
      States that Vitamin D is one of the critical nutrients with the best evidence for cognitive function and reducing the risk of dementia.
    • 13 Jul 2026 · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning.
    • 13 Jul 2026 · Vitamin K · uses · X ↗
      Takes 90 mcg of Vitamin K2 in the morning.
    • 12 Jul 2026 · uses · X ↗
      He takes 5,000 IU of Vitamin D3 in the morning for overall health.
    • 12 Jul 2026 · Vitamin K · uses · X ↗
      He takes 90 mcg of Vitamin K2 in the morning for overall health.
    • 6 Jul 2026 · uses · X ↗
      Takes 5000 IU of Vitamin D3 in the morning.
    • 6 Jul 2026 · Vitamin K · uses · X ↗
      Takes 100 mcg of Vitamin K2 in the morning.
    • 22 Jun 2026 · uses · X ↗
      Takes 5,000 IU of Vitamin D3 in the morning for general health.
    • 22 Jun 2026 · Vitamin K · uses · X ↗
      Takes 90 mcg of Vitamin K2 in the morning for general health.
    • 17 Jun 2026 · uses · X ↗
      Takes 5000 IU of Vitamin D3 every day for longevity.
  • Peter Attia · Vitamin D · uses
    • 4 Jan 2026 · uses · YouTube ↗
      Lists vitamin D as one of her staple supplements.
    • 16 Nov 2025 · neutral · YouTube ↗
      Notes that several studies show patients taking vitamin D can reduce TPO levels and prolong the honeymoon period of Hashimoto's disease.
    • 6 Aug 2025 · neutral · YouTube ↗
      States that in mouse studies, there was a combined effect of alpha ketoglutarate with vitamin D for both sexes.
    • 3 Aug 2025 · neutral · YouTube ↗
      Uses vitamin D as an example of how people might dismiss its efficacy due to failed clinical trials that didn't adjust the dose or measure levels.
    • 20 Jul 2025 · neutral · YouTube ↗
      In mouse studies, Peter Attia's team found a combined effect of AKG with Vitamin D for both sexes.
    • 10 Jul 2025 · neutral · YouTube ↗
      Suggests that supplementing with lots of vitamin D might help overcome the negative effects of phenytoin on bone health by improving calcium absorption, though he is unaware of studies on this.
    • 9 Jul 2025 · recommends · YouTube ↗
      Recommends Vitamin D3 as one of the 'big three' micronutrients for bone health, suggesting a daily intake of 800 to 1,000 IU, which can be obtained through sunlight or supplementation.
    • 6 Jul 2025 · neutral · YouTube ↗
      Suggests that supplementing with lots of vitamin D might overcome the negative effects of phenytoin on bone health by counteracting increased catabolism of vitamin D and subsequent decreased calcium absorption.
    • 8 Jun 2025 · recommends · YouTube ↗
      Recommends vitamin D for people who tend to be vitamin D deficient, such as those living in Portland, Oregon.
    • 17 Mar 2025 · neutral · Instagram ↗
      Discusses evaluating vitamin D, understanding deficiency, and optimal levels.
    • Date not recorded · Vitamin K · uses · Website ↗
      Takes 100 mcg of Vitamin K2 in the morning to maintain levels.

RAL Summary

Members OnlyTier 2 for Bone Health

Several pooled analyses show vitamin K2 improves spine bone density in postmenopausal women with thinning bones [1][2]. More than 7,000 reviews are 80% positive.

Where the evidence disagrees: 16 of the 85 human studies found no effect.

More Details

Members OnlyBody systems · Combine with · Possible side effects

Body systems: Skeletal system

Combine with: To further enhance bone health alongside Vitamin D and K2, consider supplementing with Calcium, as Vitamin D is crucial for its absorption into the bones. Magnesium is another vital mineral that works synergistically with both Vitamin D and K2, playing a role in bone formation and helping to activate Vitamin D. Additionally, a high-quality collagen supplement can provide the necessary protein matrix for strong bones, complementing the mineral deposition facilitated by D and K2.

Possible side effects: Studies reported more mild side effects with vitamin K2 but no serious ones. Reviewers mainly complained about the hard-to-use dropper, not about side effects.

Supplement Facts

Vitamin D3 25 mcg · Vitamin K2 200 mcg
Supplement Facts
Serving Size 2 Drop(s)
Servings Per Container 600
Amount Per Serving% Daily Value
Vitamin D325 mcg
Vitamin K2 (Menatetrenone)200 mcg

Other ingredients: Mixed Tocopherols, Medium Chain Triglycerides.

Label source: Thorne · Report a label change

Show entire label
The Thorne Vitamin D/K2 Liquid label
Vitamin D/K2 Liquid

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Our articles on this subject

Graded October 26, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.