Vitamins and Healthy Supplements.
Last updated: June 20, 2020

How we pick our products

16Products analysed

32Hours invested

13Studies researched

115Comments collected

If you are passionate about supplements, it is likely that you are well aware of the debate surrounding vitamin D3.  Although this nutrient has lots of benefits for the health of bones and tissue, its detractors advise that continued consumption of D3 can be debilitating to the health of blood vessels in the medium and long term.

A vitamin that has until now been underestimated, menaquinone (or K2), seems to be able to boost the beneficial effects of vitamin D3, while at the same time protecting against its more harmful side effects. Seems to good to be true? Keep reading to find out more about this potent combination of vitamins!


Key Facts

  • Vitamin D3, or colecalciferol, is a form of vitamin D which is present in foods derived from animals. Also it is synthesised by exposure to direct sunlight.
  • Some studies have linked the excessive consumption of vitamin D supplements to calcium buildup in blood vessels, which can be harmful to your health.
  • Vitamin K2, until now recommended as a vital element for coagulation, can reduce calcium buildup in arteries and make the consumption of vitamin D3 supplements safer.

Our selection: The best vitamin D3 and K2 supplements in the Australian market

The boom of vitamin D3 and K2 supplements has made finding the perfect product a difficult task. In this guide we have worked hard to find the best vitamin D3 and K2 supplements on the market in 2021. The following list that you are about to read, gives details about the five best products based on their effectiveness, safety and value for money.

Bronson Vitamin K2 (MK7) with D3 Supplement

This formula not only promotes the proper absorption of calcium with D3, but the correct distribution to your bones where you need it most. Manufactured in the USA with quality ingredients at an FDA cGMP certified facility. Recommended by nutritional scientists like Nobel Prize Winner, Dr. Linus Pauling.

Nothing but rave reviews from buyers of this product about its potent effects. Users note feeling more energetic within just a few days of adding this supplement to their health regime. Other users have reported an increase in vitamin D levels and platelet count within only a few weeks. Bronson also get a big tick of approval for their great customer service.

NOW Foods Vitamin D3 + K2

The main sources of vitamin D3 and K2 are from animal-based products. Here we have a vegetarian option from NOW foods. It supports cardiovascular and bone health and also improves your immune system, while being GMO, gluten, wheat, dairy, soy and egg free. The capsules are small and easy to swallow.

As with the product from Bronson, users love this supplement from NOW Foods. They report feeling more energetic and less lethargic within a few short days, while their blood tests are showing big improvements within weeks. This product is also great value for money which has been a big hit with buyers.

Naturelo Calcium, Magnesium, Potassium & Vitamin D3, C & K2

This product is plant-based and includes raw calcium from red algae, vitamin C from organic acerola cherries and vitamin D3 from lichen. It provides 600 mg of elemental calcium from two different sources, 200 mg of natural magnesium glycinate, 1000 IU of vitamin D3, and 7 other important vitamins and minerals. For better absorption, this product includes 9 critical co-factors: magnesium, zinc, manganese, potassium, boron, silicon, as well as vitamins C, D, & K.

Top reviews from users of this product who are looking for a supplement that not only includes D3 and K2, but also magnesium and calcium. People taking this supplement report benefits such as stronger and healthier fingernails, and improved results in their bone density tests after only a few months of adding this product to their regime.

Herbs of Gold Calcium Citrate, Magnesium, Vitamin K2 & D3 Plus

This product from Herbs of Gold is great for vegans or people with allergies. It contains no egg, milk, peanut, soy, nuts, yeast, gluten, lactose, artificial colours, flavourings or preservatives. Like the supplement from Naturelo, this product also contains calcium and magnesium.

Feedback from buyers has been largely positive. Users report feeling more energetic after only a few days of use. The only negative would be the price, which is a little more expensive than some of the other options on our list, and also the size of the tablets. Some users say they must be cut into quarters, as they are too large to swallow whole.

Australian NaturalCare Calcium, Vitamin D3 and K2

Australian NaturalCare calcium vitamin D3 and K2 for joint bones and muscles supports optimal bone health. This new formula contains three of the most important nutrients in bone health: calcium, vitamin D3 and vitamin K2. Calcium is central to the structural integrity of the bone matrix, thus improving bone density and strength. Vitamin D3 and K2 work together to direct calcium to your bones and to enhance calcium absorption.

This Australian company is very popular among users of various supplements. They provide high quality products at very reasonable prices. Plus their products are Australian made, so you are supporting a local business and you can be sure you are buying a safe product.

Shopping Guide: Everything you should know about Vitamin D3 & K2 supplements

Vitamin D is vital for maintaining the health of your bones, heart and brain. In its most potent form, vitamin D3 stimulates the absorption of calcium from food. At the same time, vitamin K2 ensures that calcium is deposited in your bones and teeth, where it is needed most.


Sunscreen is vital for protecting your skin from the sun’s harmful rays. However, its use will prevent the synthesis of vitamin D through your skin.
(Source: Maridav:19808581/

What is vitamin D3?

Vitamins are molecules that are indispensable to the proper functionality of the human body. It uses these molecules in small amounts, as they are not able to be synthesised from anywhere else in our system. Instead, they need to be absorbed from a healthy diet. The term “vitamin” is derived from the Latin words vita (life) and anima (soul).

Vitamina D  is a liposoluble molecule (which means it can be found in different types of fats). Although there are five different variants of this vitamin, the human body is only able to absorb two: vitamin D2 or ergocalciferol and vitamin D3 or colecalciferol. Colecalciferol is more potent than ergocalciferol.

Vitamin D2 can be found in vegetables and in certain types of mushrooms, while eating food products derived from animals increases reserves of vitamin D3 in the body. Exposure to sunlight, surprisingly, is also capable of promoting the production of colecalciferol. This is why vitamin D3 is known as the “vitamin of the sun”.

Why is vitamin D3 considered superior to vitamin D2?

Both colecalciferol and ergocalciferol are inactive forms of vitamin D. Before being able to function beneficially in the human body, both substances must be metabolised by the liver and the kidneys. The key difference between vitamin D2 and D3 is their origin.

  • Vitamin D2 or ergocalciferol is found in some plant-based foods, such as certain mushrooms, which are able to produce it through exposure to sunlight.
  • Vitamina D3 or colecalciferol is present in many animal-based food products, such as fish, eggs and dairy products. It is also absorbed by the skin when exposed to direct sunlight.

Nevertheless, many studies have proven that vitamin D3 produces a higher conversion of calcitrol compared to vitamin D2. D3 stabilises vitamin D levels and maintains them at a range 60% higher than D2. For this reason, colecalciferol is held in high esteem by the majority of nutritional experts and is widely recommended.

Unfortunately, most vitamin D3 supplements do contain some type of ingredient derived from an animal product (usually fish oil). This is an issue for vegans and vegetarians, who need to expose themselves to direct sunlight for 30 minutes every day, if they want to raise their vitamin D3 reserves.

Did you know that the human body is capable of synthesising vitamin D3 from exposure to sunlight? This is why some experts prefer to consider it as a hormone, rather than as a vitamin.

What is the function of vitamin D3?

Vitamin D3 is absorbed from the food you eat, or from exposure to sunlight, into the bloodstream. There it is metabolised by the liver and kidneys into its active form (calcitriol), and is then ready to be used whenever needed. Its most important functions can be summed up as follows:

  • Increases the absorption of calcium in the intestines
  • Controls the levels of phosphorus and calcium in the kidneys
  • Creates new bones
  • Strengthens teeth
  • Replaces deteriorated bone tissue
  • Develops muscular contractions
  • Reduces blood pressure
  • Controls inflammation
  • Strengthens the immune system
  • Slows ageing in neural tissue
  • Regulates emotional state
  • Regulates the production of hormones (oestrogen and testosterone)
  • Controls appetite

99% of vitamin D stored in the body is used to regulate the levels of calcium in various tissues. The other 1% plays a vital role in the functionality of different processes which are essential to the well-being of the body, such as maintaining  constant weight and developing strong muscles.


Paté is a rich source of vitamin K2.
(Source: Budarin: 76332780/

What is vitamin K2?

Vitamin K, like vitamin D, is a liposoluble substance which can be absorbed more easily when consumed with certain types of fats. In 1935, Dr Henrik Dam from Denmark discovered that this molecule is vital for coagulation and named vitamin K in accordance with this function (from the German koagulation).

There are five variants of this vitamin in existence. The two naturally derived forms are vitamin K1 or phylloquinone (abundant in leafy greens) and vitamin K2 or menaquinone (present in animal-based food products and fermented foods such as cheese or soy-based products such as nattō).

Did you know that a vitamin K deficiency can provoke haemorrhages in newborns? This is why an injection of this vitamin is recommended for babies immediately after they have been born.

What is the difference between vitamin K2 and vitamin K1?

Until a few years ago, it was believed that the only difference between vitamin K1 and vitamin K2 was their origin, and that the body was easily able to transform phylloquinone into menaquinone. However, some experts have started to suggest that these 2 substances should be considered as being very different to each other.

Although both vitamins are equally essential elements, necessary for the activation of proteins which regulate coagulation and other metabolic processes in the body, vitamin K2 is known to lower deposits of calcium in blood vessels and improve vascular health. Vitamin K1, on the other hand, does not perform this function.

Various studies have shown that people of advanced age (especially women) who maintain elevated levels of vitamin K2 report lower incidences of of osteoporosis and calcification of the arteries, something that does not happen among consumers of K1. This is the main difference between the two molecules.

What role does vitamin K2 play in our bodies?

Vitamin K, in all its forms, is a molecule which contributes to the process of blood coagulation. It also regulates the metabolism and is an antioxidant which prevents against dementia and various types of cancer (especially colon cancer and breast cancer).

Vitamin K2 possesses several characteristics which appear to be found exclusively in this substance. You can consult the table below to compare the benefits of all forms of vitamin K on one side, and those particular to menaquinone on the other.

Functions of vitamin K Functions exclusively performed by vitamin K2
Performs coagulation Mineralisation of bones
Formation of bones Prevention of arterial calcification
Neuroprotection Prevention of calcification of the heart
Cellular antioxidant Strengthens the enamel of teeth
Boosts immunity Cutaneous cellular antioxidant
Energy metabolism regulator Regulates hormone production (raises testosterone in men and lowers it in women)

Vitamin K2 is a nutrient that has not been extensively studied until fairly recently. More testing is needed to officially confirm its potential health benefits. However, the most recent studies have yielded very promising results and are confirming how indispensable vitamin K2 is for our general health.

What is the relationship between vitamin D3 and vitamin K2?

Vitamin D3 helps the absorption of of calcium and the mineralisation of bones and teeth. However, some experts fear that very high levels of vitamin D and calcium could result in the deposit of this mineral in places where it can be detrimental to your health. For example, in the walls of blood vessels or in the kidneys.

Vitamin K2 also contributes to the mineralisation of bones. It activates a group of very fine proteins present in the tissue of bones and teeth. It increases the quantity of minerals which are deposited in bones, and decreases the concentration of calcium, which has the capacity to be detrimental to the function of other organs in the body.

For this reason, many nutrition experts consider these vitamins as synergistic. That means that they are capable of working together to increase the potency of the beneficial effects they provide. Vitamin K2 permits vitamin D3 to perform at an enhanced capacity, and at the same time, it prevents the adverse side effects associated with supplements containing heavy doses of this substance.

What are the recommended doses of vitamin D3 and vitamin K2?

The recommended dose of each nutrient is determined in accordance with various scientific criteria and are ratified by different international organisations. The the case of vitamin D3 and K2, the recommended daily intake (RDI) depends on a wide range of variables, such as age, sex and the particular state of health of each individual.

In the case of vitamin D3, the RDI can be quantified by the International Unit (IU), which is a parameter that measures the level of biological activity in nanograms (ng) or in micrograms (μg). The RDI for vitamin K2 is measured in micrograms. In the following table, you can find the RDI for each of these substances:

Group RDI vitamin D3 RDI vitamin K2 (ug)
Babies 0-6 months 400 IU or 10 μg 2 μg
Babies 6-12 months 400 IU or 10 μg 2.5 μg
Children 1-3 years 600 IU or 15 μg 30 μg
Children 4-8 years 600 IU or 15 μg 55 μg
Adolescents 9-18 years 600 IU or 15 μg 60 μg
Adults up to 70 years 600 IU or 15 μg 75 μg
Women over 70 years 800 IU or 20 μg 90 μg
Men over 70 years 800 IU or 20 μg 120 μg

What is the effect of a vitamin D3 and K2 deficiency?

Foods rich in vitamin K2 are very rare in a western diet. The body will mainly use vitamin K1, which is much more abundant in our food. This vitamin is capable of enhancing the functionality of blood coagulation, but it will not provide the same quantity of benefits as vitamin K2.

Vitamin D3 deficiency is also very common. It is estimated that around 30-80% of the population worldwide suffers from some type of deficiency of this vitamin, caused mainly by a reduced exposure to sunlight, the overuse of sunscreen and the rise in the number of people living a sedentary lifestyle.

fried salmon

Salmon is delicious and also rich in vitamin D3.
(Source: Baibakova: 34039849/

Certain people are at a much higher risk of suffering from a hypovitaminosis of D3 or K3 than the general population. The people who appear on the following list should carefully plan their diet, if they want to avoid developing some type of imbalance relating to the absorption or the accumulation of these vitamins:

  • People over the age of 60: The capacity to absorb, store and synthesise these vitamins decreases over time.
  • People who work night shift, in an office, and students: Exposure to sunlight is lower than the suggested levels recommended to maintain stores of vitamin D3 within a healthy range.
  • People with dark skin: Skin which contains more melanin is less capable of absorbing the rays of the sun and creating vitamin D3.
  • Vegans and vegetarians: Colecalciferol and menaquinone are difficult to find in a plant-based diet, which increases the probability of a deficiency of these nutrients.
  • People who frequently use sunscreen: While blocking out ultraviolet radiation, the absorption of vitamin D3 from the sun is impeded by the use of sunscreen.
  • People with chronic intestinal illness: The absorption of all vitamins (D3 and K2 included) is affected in cases of malabsorption (as with ulcerative colitis or Crohn’s disease).
  • People who regularly take antibiotics: Good bacteria in the intestines help the absorption of vitamin K2. The destruction of these bacteria by the use of antibiotics affects the levels of this vitamin in the body.
  • People who consume excessive amounts of alcohol: Alcohol is an oxidant which limits the absorption of K2 and prevents it from functioning properly.

What issues can arise from an imbalance of vitamin D2 and K2?

The effect of a vitamin D3 deficiency can be somewhat difficult to identify, it causes tiredness and a general feeling of malaise.  If this condition is not corrected, issues can arise when metabolising calcium and other minerals. This can lead to osteoporosis, joint pain and lesions on bones and muscles.

Issues resulting from a vitamin K2 deficiency will significantly reduce the body’s capacity to coagulate blood. Even light physical contact can result in haematomas, wounds or bleeding (for example haemorrhages in the gums after the brushing of teeth). For women in particular, there are lots of serious complications that can arise.

woman reading

A vitamin D3 and K2 supplement is especially beneficial to older women and helps the prevention of osteoporosis. (Source: Shironosov: 31375574/

On the other hand, if the levels of vitamin D3 remain high, but the levels of vitamin K2 decrease, their is a greater risk that calcium derived from food or supplements can be deposited in arteries, causing hypertension and harming the kidneys and the heart in a slow and insidious manner.

Dr. John CannellMedical Doctor
“50,000-63,000 individuals in the United States and 19,000-25,000 in the UK die prematurely from cancer annually due to insufficient vitamin D”.

How can I increase my levels of vitamin D3 and K2?

All the experts agree that exposure to the sun is the best way to achieve an increase in your levels of vitamin D3. 15-30 minutes every day spent out in the sun is sufficient time to adsorb the quantity of colecalciferol needed to maintain a healthy level. Although, the use of sunscreen can make obtaining vitamin D3 difficult by this method.

For people who do not want to expose themselves to solar radiation, there is the option of getting this vitamin from the foods consumed as part of their diet. Animal-based foods like chicken livers, salmon and egg yolk are especially rich in vitamin D3. Unfortunately, there are no sources of vegan foods containing this vitamin.

girl using an vitamin spay

An oral spray is a simple way of easily supplementing your vitamin D3 and K2 intake.
(Source: Guillem: 89097091/

Getting enough Vitamin K2 is much more difficult, especially following a western diet. This nutrient is found only in small quantities in certain animal-based food products, such as goose livers or free range chicken eggs. It is more abundantly found in fermented foods such as nattō and certain cheeses.

What foods are a rich source of vitamin D3?

You can find large quantities of vitamin D3 in animal-based products such as fish, eggs and dairy. The following table provides an overview, and includes the main sources of vitamin D3 with the concentration of colecalciferol in relation to the recommended daily intake or RDI for an adult:

Food Approx. concentration (IU) % RDI (for an adult)
Cod liver oil (1 tablespoon) 500 80
Salmon (75 g) 350 60
Mackerel(75 g) 200 30
Tuna (75 g) 150 25
Sardines (75 g) 150 25
Fortified milk (250 ml) 100 15
Egg yolk (unit) 45 8
Veal livers (75 g) 35 6
Fortified margarine (1 tablespoon) 30 5

Although the absorption of vitamin D3 from food is less efficient than from exposure to sunlight, a varied diet, rich in these products will be able to provide a sufficient quantity of colecalciferol for healthy bones. It will also generally improve mental and cardiac health.

What foods are a rich source of vitamin K2?

The quantity of vitamin K2 present in animal-based products depends mainly of the quality and type of food fed to the animals while they are young and developing. Free range chicken eggs, for example, contain a larger amount of vitamin K2 than barn laid eggs.

Fermented foods that are rich in menaquinone should be refrigerated and stored properly to avoid the deterioration of the K2 they contain. The following table lists the various foods that are rich in vitamin K2, both animal-based and fermented:

Food Approx. concentration (ɥg) % RDI(For an adult)
Nattō (100g) 1000 1300
Goose paté (100g) 369 500
Hard cheeses: parmesan, emmental and gruyere (100g) 75 100
Soft cheeses (100g) 50 65
Free range egg yolk 32 45
Barn laid egg yolk 15 20
Butter (100g) 15 20
Chicken breast (100g) 9 12
Veal livers (100g) 5 7
Full cream milk (100 ml) 1 1

Who should take a vitamin D3 and K2 supplement?

As a large percentage of the population present with insufficient levels of vitamin D3 or vitamin K2, some nutritionists advise that all people should supplement their intake of these nutrients. Other experts are more prudent and recommend an extra dose of these vitamins only for the following groups of people:

  • People over the age of 60
  • Strict vegans and vegetarians
  • People who are not often exposed to direct sunlight
  • Postmenopausal women,especially if they are suffering from a loss in bone density
  • People with obesity
  • People who have had bariatric surgery or some type of intestinal resection
  • People with cardiovascular problems (hypertension, heart failure)
  • People who follow very restrictive or unbalanced diets
  • People with kidney failure

The combination of vitamin D3 and K2 is particularly beneficial to people with a family history of cardiac arrest associated with coronary artery calcification (CAC). In this case, vitamin K2 impedes the buildup of calcium in arteries, which can be a side effect of taking a vitamin D3 supplement.

What types of vitamin D3 and K2 supplements are available on the market?

Vitamin D3 and K2 supplements are available as either capsules, drops or powder. The colecalciferol present in these products is derived from animal-based products in the majority of cases. Although, several manufacturers use mushrooms capable of producing a vegan form of vitamin D3.

In the case of vitamin K2, there are numerous isoforms (or molecular variants) that are available for use as a food supplement. The varieties of vitamin K2 most commonly used in supplements are known as “vitamin K2 MK-4” and “vitamin K2 MK-7”. Their effect on the body can be easily summed up as follows:

  • Vitamin K2 MK-4: MK-4 is vitamin K2 in its most active form. This substance is rapidly absorbed and stored in the brain, arteries, the pancreas and saliva glands.
  • Vitamin K2 MK-7: MK-7 is the form of vitamin K2 that penetrates most easily into bone and liver tissue. This is where vitamin K2 is metabolised into MK-4 to produce all of its beneficial effects.

Experts advise the use of a vitamin D3 and K2 supplement which contains equal amounts of both isoforms of menaquinone. This is so the vitamin K2 can evenly reach every part of the body where it is required, allowing bones, arteries, kidneys and brain tissue to be equally protected.

Dr Joachim SchwarzMedical Doctor
“An ingestion of sun dried mushrooms can contribute to the supply of vitamin D”.

How much do vitamin D3 and K2 supplements cost?

The cost of vitamin D3 and K2 supplements is only a little more than the cost of supplements containing only colecalciferol – around $30 per container. Most of these products include a sufficient quantity of the product needed to last for three months or even longer. This is why these products are such great value for money.

100% vegan supplements, products that contain other vitamins, minerals or plant extracts and those available from well known-brands come with a higher price tag. However, there are often limited time promotions and sales that can make these supplements a much less expensive option.


Cod liver oil is a rich source of both omega-3 essential fatty acids and also vitamin D3.
(Fuente: Geel: 92630892/

How do I take my vitamin D3 and K2 supplement?

Combined vitamin D3 y K2 supplements should be taken according to the manufacturer’s instructions. Their use is simple and in general, it is only necessary to take one supplement a day. In the following paragraphs you will find answers to the most commonly asked questions from people using these products:

  • How much should I take? It is recommended to chose a a supplement that provides a daily recommended intake (RDI) of vitamin D3 and K3. The majority of the products out on the market offer much higher amounts of colecalciferol and menaquinone than the RDI. This means that a single daily dose of a supplement will be sufficient for most people.
  • What proportion of each vitamin should I take? You should take an adequate amount of vitamin K2 to ensure that the vitamin D3 functions properly, and also to prevent arterial hardening which results from the improper depositing of calcium. For this to be achieved, it is recommended that the chosen supplement should contain at least 45 ɥg of vitamin K2 per 1000 IU of colecalciferol.
  • Should I take these supplements with or without food? As both vitamin D3 and vitamin K2 are liposoluble molecules, they will be absorbed more efficiently if they are taken with food, especially when accompanied by fatty or oily foods. A salad dressed with olive oil, for example, will help the supplement to assimilate more readily.

What kind of benefits can I expect from my vitamin D3 and K2 supplement?

Keeping the levels of vitamin D3 and K2 within the recommended range will result in a much better general state of physical, mental and metabolic health. These molecules act in a synergistic way, and increase the potency of the benefits of each vitamin. This provides numerous benefits, which you will see summed up in the following list:

  • An increase of muscle performance (strength and endurance)
  • A decrease in blood pressure
  • An increase in bone density with lowered occurrence of fractures
  • A decrease in the occurrence of heart or coronary disease
  • An improvement of the functionality of blood vessels, whit a decrease in the prevalence of varicose veins
  • A strengthening of tooth enamel and a lowered occurrence of tooth decay
  • An increase in energy levels
  • Protection against various infections (colds, flu and colds)
  • An general improvement of mental health
  • The preservation of mental faculties, especially of memory
  • A decrease of LDL cholesterol (or “bad” cholesterol)
  • Increases coagulation and helps to stop bleeding
  • An improvement in skin appearance
  • Relief from the symptoms of psoriasis and other chronic inflammatory diseases
  • Bruises will heal much more quickly
  • Regulation of the production of testosterone in men
  • An improvement of the symptoms of Polycystic Ovarian Syndrome for women
  • Increased insulin response, with lowered levels of blood glucose

Many studies have confirmed the link between optimum levels of these vitamins and lower incidences of cancer. Various articles have been published (on breast cancer, colon cancer and prostate cancer among others), which offer promising results for the potential antitumoral properties of these substances.

Is it possible to take too much of a combination of vitamin D3 and K2?

Vitamin D3 can be stored in fat tissue, and it is difficult to eliminate. If an excessive amount of supplements of this vitamin are taken, some unpleasant side effects may present. These can include weakness and vomiting. Luckily, vitamin K2 helps to reduce the intensity of these symptoms.

Vitamin K2 is also a liposoluble substance. Paradoxically, toxic side effects from the consumption of K2 have not been reported, even at extremely high doses (100 or more times higher than the RDI). This is why there is no consensus for an upper daily limit for the intake of menaquinone.

Did you know that K3 (the synthetic homologue of vitamin K) is toxic in high doses? It is very important not to confuse it with vitamin K2.

It is generally advised to avoid ingesting more than 4000 IU of vitamin D3 per day. It is also important to choose a supplement that contains 45 ug of menaquinone per 1000 IU of colecalciferol, which will help to mitigate the unwanted side effects. Although there is no limit agreed upon for the safe amount of vitamin K2 that can be taken daily, it shouldn’t be more than the RDI.

What adverse side effects can be caused by a vitamin D3 and K2 supplement?

The use of any type of supplement can cause major or minor side effects. The combination of vitamin D3 and K2 can cause some unwanted side effects, although they are usually only the cause of minor discomfort, without any serious clinical repercussions.

Common adverse side effects: It is possible that some minor adverse side effects can occur. These can be things like flatulence, abdominal pain and swelling of the belly. These side effects dissipate gradually, once the body gets used to digesting the supplement.

Less common adverse side effects: Some unpleasant symptoms have been reported with the use of vitamin D3 and K2 supplements, such as nausea, vomiting and severe abdominal pain. These side effects are much less common than those mentioned in the above category. They may require an adjustment of the daily dose, or the supplement may need to stop being taken altogether.

Very uncommon adverse side effects: These are very rare and often appear with more serious symptoms, such as intense vomiting and diarrhoea, loss of appetite and muscle deterioration. In this case it is recommended to immediately cease taking the supplement.

What are the contraindications of vitamin D3 and K2 supplements?

Although vitamin D3 and K2 supplements are generally considered to be safe, they are not free of contraindications. People who are struggling to control their levels of blood sugar should be very careful with this supplement, which can cause an expected reduction of glucose levels.

People with liver or kidney problems have a sensitive metabolism and should consult a health professional before starting to take these vitamins. It is also not recommended for women who are pregnant or breastfeeding to take this supplement without medical advice.

Lastly, it is necessary to take into account any possible adverse interactions between these vitamins and more well-known  medical treatments. If you regularly consume pharmaceutical drugs that appear on the following list, consult your doctor before you begin taking vitamin D3 and K2 supplements:

  • Warfarin (anticoagulant vitamin K antagonist)
  • Antiretrovirals
  • Treatment for chronic renal failure
  • Antiepileptics
  • Antacids
  • Lipid-lowering drugs (medicines to lower cholesterol) such as Orlistat
  • Medication for the treatment of psoriasis
  • Some antibiotics, such as tetracyclines
  • Digoxin (antiarrhythmic treatment)
  • Antihypertensive drugs
  • Thyroid hormone
  • Certain diuretics
  • Corticoids
  • Laxatives

Shopping Criteria

Here we set out the most important criteria you should keep in mind when choosing a vitamin D3 and K2 supplement, so that you are confident that it suits your needs. The following guide lists the most commonly found features of this type of product. Taking these into consideration when making your purchase, will help you to choose a product that is of high quality.


In rare cases, allergic reactions can happen with the use of vitamin D3 and K2 supplements. Sometimes symptoms of hypersensitivity can be caused by the bulking agents used in a certain product. Carefully check the ingredients of the supplement you are thinking of buying, if you are allergic to anything like gluten or dairy.

Vegan and vegetarian friendly

It can be challenging to find vitamin D3 and K2 supplements for vegans and vegetarians. Cholecalciferol is a compound found almost exclusively in animal-based foods. This is the reason why many vegans and vegetarians prefer to use vitamin D2 supplements, that can be made from plant-based ingredients.

Recently, there has been a surge in the number of vitamin D3 and K2 supplements suitable for vegans and vegetarians. According to manufactures, the colecalciferol is able to be obtained from mushrooms or lichens that are specially cultivated for this purpose. These can be a great option for anyone who doesn’t want to miss out on adding these supplements to their regime.


Certain vitamin D3 and K2 supplements can contain minerals like calcium, phosphorus or magnesium. Many experts recommend choosing a supplement that contains magnesium. The absorption of calcium and phosphorus is already increased by the ingestion of vitamin D3, so it is not necessary to take an additional supplement for these minerals.


It is advisable that you carefully check the the dose of vitamin D3 of your supplement of colecalciferol with the level of menaquinone it contains. The dose of D3 should never exceed 4000 IU. A much safer range is taking somewhere within the RDI of 800-100 IU.

Don’t forget that the dose of vitamin K2 should be equal to the dose of D3.

Value for money

The beneficial effects that are achieved from taking vitamin D3 and K2 supplements can be felt within a few short weeks of beginning the treatment. However, these products must be used for at least 6 months to resolve an acute case of hypovitaminosis. You should always buy a large quantity of supplements at the one time, which will save you money in the long term.

How it is taken?

In the case of vitamin D3 and K2 supplements, the method by which they are taken will not excessively influence either the absorption or the effectiveness of the product. Therefore, we recommend that you just choose the one that you prefer. There are many different products which allow you to take your supplements in a variety of ways:

  • Tablets: These tablets have a cover that gives them a pleasant taste and and makes them easy to swallow.
  • Soft Capsules: This type of supplement is especially suitable for people who have difficulty swallowing large pills.
  • Oral Spray: This ingenious method allows you to forget about taking pills altogether. Some products are able to be sprayed on food and can even be used as a salad dressing.
  • Drops: This method uses an eyedropper that allows you to easily measure the dose of supplement you are taking.
  • Powder: If you opt for this method, you can mix the powder into purees, drinks or smoothies. It also allows the dose to be adjusted more precisely than other methods.


The combination of vitamin D3 and K2 has made a big impression in the world of supplements. When taken together, these two molecules make an unbeatable team, which will provide the advantages of colecalciferol, and at the same time, lower the severity of the unwanted side effects. Its antioxidant properties make this supplement an important part of any health regime.

If you follow our advice, you can get the most out of your vitamin D3 and K2 supplement. If used intelligently, this product will protect your bones and your cardiovascular system at the same time. Now you will be able to enjoy a more active life, free from the ailments you have endured for years. Make sure you add this incredible supplement to your regime!

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