Vitamin D3® — The Supplement the UK Can't Afford to Skip.
5,000IU D3 per capsule. Immune function. Muscle function. Bone health. One capsule daily.
The UK has a Vitamin D problem. Limited sunlight and the demands of training create a widespread deficiency affecting immune function, muscle strength, bone density and recovery — often without people making the connection.
Vitamin D3® delivers 5,000IU of Cholecalciferol — the most bioavailable form of Vitamin D, mirroring what the body produces through sun exposure — in a single daily capsule. At 2,500% of the NRV, this is the high-strength dose that actually moves the needle.
Calcium and Phosphorus are included to complement the bone health benefits — the two minerals most directly involved in skeletal mineralisation.
One capsule per day. The simplest possible upgrade with some of the broadest benefits.
Best for
Athletes and active individuals in the UK
Those with limited sun exposure
Immune function and year-round health maintenance
Bone density and muscle function support
Why it works
Vitamin D3 — Cholecalciferol (5,000IU — 2,500% NRV) Contributes to normal immune function, muscle function and the maintenance of normal bones.
Calcium (175mg — 22% NRV) Works with Vitamin D to support normal bone density and mineralisation.
Phosphorus (135mg — 20% NRV) Essential mineral for bone health and energy metabolism.
What makes it different
5,000IU D3 — a dose that makes a difference
Cholecalciferol — the most bioavailable form
Calcium and Phosphorus included for bone support
One capsule per day — 90-day supply
Suitable for vegetarians. Made in the UK.
How to Use
Take one capsule per day with water. Do not exceed recommended daily dose.
Since 1997 Bio-Synergy has been setting standards in sports nutrition. Certified B Corporation®. Made in the UK. Independently tested. Used by elite and professional athletes for over 25 years.
Absolutely. All our supplements undergo rigorous testing for safety and efficacy. We adhere to the highest standards to ensure our products are free from banned substances, making them safe for athletes at all levels.
How do I know which Bio-Synergy supplement is right for me?
Our product range is designed to cater to various fitness goals, whether it's building muscle, losing weight, or enhancing endurance. For a more personalised approach we recommend a Bio-Synergy DNA test to identify the best supplement for you.
Can I take Bio-Synergy supplements with other medications?
While our supplements are safe, we recommend consulting with your doctor before starting any new supplement regimen, especially if you are currently taking other medications.
How should I store my Bio-Synergy supplements?
Keep your supplements in a cool, dry place away from direct sunlight. Make sure the cap is tightly sealed after each use to maintain their potency and freshness.
What is the return policy for Bio-Synergy supplements?
We stand behind the quality of our products. If you are not satisfied with your purchase, you can return it within 30 days for a full refund. Please visit our return policy page for detailed information.
Do Bio-Synergy supplements have any side effects?
Bio-Synergy supplements are designed to be safe and effective when used as directed. However, as with any supplement, some people may experience side effects. If you experience any adverse effects, stop use immediately and consult a healthcare professional.
How long does it take to see results from Bio-Synergy supplements?
Results can vary based on individual factors like diet, exercise, and overall health. Some may notice benefits immediately, while for others, it might take longer. Consistency and a healthy lifestyle are key to achieving the best results.
Are there any discounts available for buying Bio-Synergy supplements?
We often offer promotions and discounts. Check our website regularly, sign up for our newsletter, or follow us on social media to stay updated on our latest deals.
How long does delivery take?
Delivery is next day in the UK Monday-Thursday and 48-72 hrs at weekends. For international delivery, times will vary but generally within 7 working days
