At Epic Life, we don't guess. We test.
The results are clear: 6 out of 10 people we’ve tested have Vitamin D levels outside the “normal” range.
But data without direction is useless. Once you know where you stand, you need a plan to move forward. That’s what makes Epic Life so effective. After you receive your results, your AI Health Companion guides you instantly towards the optimal range.
Read on to discover why diet alone usually fails to fix a Vitamin D deficiency and why testing your levels is the smartest route to better health.
Spending 10-20 minutes in the sun can enhance vitamin D levels
Why low vitamin D matters
Our data shows that 59% of users fall outside the healthy range. This is not just a number on a page; it impacts your biology in three critical ways:
Immune defence
Adequate levels are essential for activating T-cells that fight infection. Deficiency is linked to increased susceptibility to respiratory infections and autoimmune conditions.
Bone and muscle health
Without sufficient Vitamin D, your body can’t absorb calcium efficiently, leading to lower bone density and reduced muscle strength.
Mood and brain health
Vitamin D receptors are found throughout the brain. Low levels are consistently correlated with an increased risk of depression and cognitive decline.
Sufficient vs. optimal: what do you need?
Most standard guidelines aim for "sufficient" (often defined as >50 nmol/L). This is the level required to avoid disease.
At Epic Life, we aim for "optimal" for longevity and performance. Leading research cites this range as 75–125 nmol/L.
The science: why are so many people deficient?
Humans evolved to generate Vitamin D through our skin via sunlight (UVB rays). However, modern life disrupts that mechanism in three specific ways:
1. The Geography Challenge If you live far from the equator (e.g., the UK or northern US), UVB rays are too weak to trigger Vitamin D synthesis for up to six months of the year (roughly October to March).
2. The Indoor Problem Many of us spend the majority of our time indoors. Glass blocks UVB rays, meaning sitting by a window won't help. Even when outside, sunscreen (essential for reducing skin cancer risk) blocks Vitamin D production.
3. The Epic Insight: Body Composition Vitamin D is fat-soluble and can get stored in adipose tissue. This means those with higher body fat often need higher intakes to raise their blood levels effectively.
How to optimise your levels
If you are deficient, you have three potential sources to fix it. Here is the reality of each:
Source 1: the Sun
Status: Unreliable Ideally, 10–20 minutes of midday sun with a large skin surface area exposed can generate significant levels of Vitamin D. However, due to the geography and lifestyle factors mentioned above, this is rarely safely achievable year-round.
Source 2: food
Status: Insufficient in isolation Very few foods naturally contain significant Vitamin D. You simply cannot eat your way out of a severe deficiency.
Wild salmon (3.5 oz): ~600–1000 IU
Farmed salmon (3.5 oz): ~250 IU
Egg yolk: ~40 IU
Source 3: supplementation
Status: Useful for 59% of our users For a significant number of people, supplementation is the only viable way to reach optimal levels year-round.
Supp smart: how to supplement correctly
If you need to supplement, details matter.
Dose
Generic RDAs (often 400 IU in the UK) are usually too low to correct a deficiency. Many experts recommend 2,000 IU daily for maintenance, but your exact dose should ideally be based on blood testing to ensure safety and efficacy.
Form
Always choose Vitamin D3. It is significantly more effective at raising blood levels than Vitamin D2, the synthetic form often used in prescriptions.
Informed choice: not all supplements are created equal
The format of your supplement dictates how well your body absorbs it.
Softgels: the gold standard
Why: The Vitamin D is suspended in oil, mimicking how it is best absorbed (as it is fat-soluble).
Verdict: Excellent absorption. Ensure you take them with a meal to maximise uptake.
Tablets: the standard option
Why: Often the cheapest and most stable form. However, "dry" tablets lack the fat needed for optimal absorption, meaning they rely entirely on the meal you eat with them.
Verdict: Effective if your digestion is solid and you always take them with food. If you have gut issues, they may not be the best choice.
Oral sprays: the bio-hack
Why: These deliver the vitamin directly through the soft tissue of your mouth (buccal absorption), bypassing the digestive system.
Verdict: Research shows these are as effective as pills for most people, but they are superior for anyone with issues like IBS who struggles to absorb nutrients through the gut.
References
Hewison M. Vitamin D and immune function: an overview. Proceedings of the Nutrition Society. 2012 Feb;71(1):50-61.
Holick MF. Vitamin D and bone health. The Journal of nutrition. 1996 Apr 1;126:1159S-64S.
Lansdowne AT, Provost SC. Vitamin D3 enhances mood in healthy subjects during winter. Psychopharmacology. 1998 Feb;135(4):319-23.
Dawson-Hughes B, Harris SS, Lichtenstein AH, Dolnikowski G, Palermo NJ, Rasmussen H. Dietary fat increases vitamin D-3 absorption. Journal of the Academy of Nutrition and Dietetics. 2015 Feb 1;115(2):225-30.
Armas LA, Hollis BW, Heaney RP. Vitamin D2 is much less effective than vitamin D3 in humans. The Journal of Clinical Endocrinology & Metabolism. 2004 Nov 1;89(11):5387-91.
Satia MC, Mukim AG, Tibrewala KD, Bhavsar MS. A randomized two way cross over study for comparison of absorption of vitamin D3 buccal spray and soft gelatin capsule formulation in healthy subjects and in patients with intestinal malabsorption. Nutrition journal. 2015 Oct 29;14(1):114.
