Vitamin D3 Complete – Barefoot Nutrition
Vitamin D3 Complete
Vitamin D3 Complete

Vitamin D3 Complete

Why D3 Complete is a Better Choice:

  • Healthful level of D3 at 4000iu
  • Co-factors included to enable proper absorption and utilisation of vitamin D
  • All nutrients in highly absorbable forms
  • Paleo friendly
  • No artificial fillers or agents
  • 100% naturally fermented (pullulan) capsule. 
  • Fully recyclable glass bottle and metal lid. (one less plastic bottle in the sea!) 


Supplement Facts:

Vitamin D3 : 4000iu

Vitamin K2 (Mk-7) : 100 micrograms

Magnesium Glycinate : 60mg

Zinc picolinate:  8mg

Boron :  3mg



Rice flour, Magnesium glycinate, Zinc picolinate, Boron citrate, Vitamin D3 (Cholecalciferol), Vitamin K2 (menaquinone-7), Vegetable capsule (pullulan)

How We Compare (Click To Enlarge)

Barefoot Nutrition Comparison Chart

How Much Vitamin-D Do I Need?

It’s been suggested that the adult body uses 3000-5000iu of vitamin D per day (Heaney et al 2003) and that current recommendations are way too low. A dose of 4000iu a day through the months of September to May (in the UK) should be enough to maintain your blood levels at around 100nmol/l (Moyad, 2009). If you don’t regularly go out in the sun in the summer, cover up in the sun or have dark skin then year round supplementation is recommended. (Scientific Advisory Committee on Nutrition, 2016). It’s important to note that there has never been a reported case of vitamin D toxicity below 10,000 iu/ day (European Food Standards Agency, 2012).

EFSA (2012). EFSA panel on dietetic products, nutrition and allergies (NDA) Scientific Opinion on the Tolerable Upper Intake Level of Vitamin D. EFSA Journal;2012; 10 (7): 2813.

Heaney, R P, 2003. Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. The American Journal of Clinical Nutrition, 77 (1), 204-210

Moyad, M A, 2009. Vitamin D: A Rapid Review. Dermatology Nursing. (1), 21 Scientific Advisory Committee on Nutrition, 2016. Vitamin D and Health.


We considered adding calcium to our bone support formula, everyone knows that calcium is vital for bone health. But through our research we’ve concluded that the risk may outweigh the reward at this point. Generally the UK population seems to have enough calcium in their diet anyway and there are studies that suggest there may be a link between supplementing calcium and increased risk of heart attack, especially in the over 50s.


Bolland MJ, et al 2010. Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis.British Medical Journal; 341: c3691

Vitamin D
  • The main source of Vitamin D is from the sun, this is only in the summer months when the UVB ultraviolet light is at the correct wavelength. (SACN 2016)
  • If you are darker skinned, or wear sunscreen, the production of vitamin D is reduced.  (SACN 2016)
  • A big proportion of the population are deficient in Vitamin D
  • Sufficient Vitamin D stores will last a few months in the body to take you through the winter.  Trouble is, no one has sufficient stores anymore!
Vitamin D

Ok so modern day life means we have to go to work indoors, wear clothes, wear sunscreen to avoid skin cancer, all adding up to a vitamin D deficiency epidemic! This is why we’ve chosen this as our first product, as we feel it’s the most important to supplement, for everyone!

We try to look at our hunter gatherer ancestry for the baseline for our recommendations.

Looking at vitamin D from an ancestral perspective, hunter gatherers from the stone age were likely to have been outside a lot and so getting a good dose of daily vitamin D. Considering our DNA has hardly changed since then, one could assume we need similar amounts to fulfil our health requirements. Comparing modern day hunter gatherers in sunny countries, these guys had an average blood level of 115 nmol/l of vitamin D. (Luxwolda et al 2012). Now compare that to government guidelines of 25nmol/l. (SACN 2016).

25nmol/l will stop you getting rickets or osteomalacia, but what about the hundreds of chemical processes that vitamin D is needed to keep you healthy?

Are you aiming to prevent disease or promote health? Being health promoters we know that 4000iu will let you achieve around 100nmol/l in your blood (Moyad M, 2009) which is a decent level without any risk of toxicity. In fact, no one has ever shown any signs of vitamin D toxicity of any dose under 10,000iu a day (EFSA, 2012).

So what about the co factors?! Vitamin D alone is good, but if you are deficient in any of it’s co factors, it’s less likely to be utilised properly. Vitamin K for example has been shown numerous times in studies to have a positive influence on bone health, working in harmony with vitamin D (Weber, 2001). It is thought to help deposit the calcium floating in the blood, in to the bones. Much better in your bones than your blood vessels!


Vitamin K comes as K1 (from leafy greens) and K2 (from organ meats, egg yolk and Natto).

K2 works with Vitamin D to deposit calcium in the right areas, such as in the bones and teeth, and prevent it from depositing in locations where it does not belong, such as the soft tissues and blood vessels (Spronk et al. 2003).

The most commonly used K2 in supplements is the cheaper version Mk-4 which is synthetic, and Mk-7 which is naturally extracted from natto.  It is known that Mk-7 stays in the body much longer than Mk-4. This gives much more constant levels of K2 in the body, 7-8 times higher than the same amount of MK-4 when taking for prolonged periods, (Schurgers et al, 2007). It was the obvious choice for us.

It’s important that you don’t take vitamin K if you are taking blood thinners, such as wharfarin.


The World Health Organisation states that 75% of the population do not reach the RDA for Magnesium.

Muscle cramps are a common symptom of magnesium deficiency and this can be made worse with vitamin d, either through sunbathing or supplementation. Abbott LG, Rude RK. Clinical manifestations of magnesium deficiency. Miner Electrolyte Metab. 1993;19(4–5):314–22.

If you are deficient in magnesium, you won’t metabolise vitamin D properly. Zofková I, Kancheva RL. The relationship between magnesium and calciotropic hormones. Magnes Res. 1995 Mar;8(1):77–84. Carpenter TO. Disturbances of vitamin D metabolism and action during clinical and experimental magnesium deficiency. Magnes Res. 1988 Dec;1(3–4):131–9.

Studies have shown that people with rickets and magnesium deficiency don’t respond to vitamin d treatment until their magnesium levels are normalised.  Reddy V, Sivakumar B. Magnesium-dependent vitamin-D-resistant rickets. Lancet. 1974 May 18;1(7864):963–5. This suggests that you need adequate levels of magnesium for vitamin D to do it’s job!

The amount of magnesium in our vitamin d complete is a great start to reducing your magnesium deficiency but we also recommend eating lots of magnesium rich leafy green veg, nuts, pumpkin and other seeds, seafood and cacao.  All staples of our hunter gatherer ancestors!

We chose the citrate version of magnesium due to its superior bioavailability.


“Boron may be an essential nutrient for animals and humans. Dietary boron influences the activity of many metabolic enzymes, as well as the metabolism of steroid hormones and several micronutrients, including calcium, magnesium, and vitamin D.” (Devirian & Volpe, 2003)

The exact action of boron for bone health is unknown, but it is thought to extend the half-life of vitamin D. (Volpe et al, 1993). Clinical studies have also shown that boron supports healthy bones by increasing blood levels of calcium absorption. It could increase  vitamin D3 stimulation by as much as 24% (Hegsted, et al 1991).

The boron in D3 complete is a helping hand to utilise your vitamin D more efficiently but we first and foremost encourage the natural consumption of boron through eating foods such as prunes, raisins, dried apricots, or avocados.


The amount of zinc in a cell influences the activity of the Vitamin D dependent genes (Craig et al, 2001). So sufficient levels are important for vitamin d to do it’s job properly. As with all nutrients, we first and foremost recommend getting zinc naturally through foods such as spinach, beef, shrimp, pumpkin seeds and garlic.

IngredientsAmount Per Serving
Vitamin D34000 iu
Vitamin K2 (MK7)100µg
Magnesium Citrate100mg
Boron Citrate3mg
Zinc Picolinate8mg

Added Ingredients: Organic brown rice flour and nothing else!
Natural vegetarian pullulan capsule.

Bottle contents: 60 capsules
Suggested daily dose: Adults only: 1 capsule per day
Do not exceed the stated amount
Not suitable for people taking blood thinning medication