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Vitamin D3

Designed for vitamin support

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INGREDIENTS

Nutritional Information

100% APPROVED

Informed Sport

Next Day Delivery

Nutritional Information

All Science in Sport products are certified under the strict guidelines of the INFORMED Sport Programme. To achieve this, an independent organization (LGC Assure) with an accredited, independent laboratory that’s been testing for banned substances for over 20 years, rigorously tests our products to detect all compounds on the World Anti-doping Association Banned Substances list.

Informed Sport

Providing assurance for athletes, All INFORMED Sport certified Science in Sport products are rigorously tested, screening for all compounds on the WADA Banned Substances list.

How It's Tested

1. Product Review

2. Lab Tests (3+)

3. Batch Tests

4. Random Tests

Supplement Testing Labs

Driven by innovation and excellence, INFORMED Sport is the leading independent supplement testing provider, specialising in drug surveillance, doping control and supplement analysis.

Next Working Day Delivery Information:

Weekdays: Orders placed before 6:30pm will be delivered the next day - including on Saturdays.
Weekends: Orders placed before 1pm will be delivered the next day - including Sundays.
Bank Holidays: Orders will not be delivered on Bank Holidays. Any orders placed on a Bank Holiday will not be collected from our warehouse until the next non-holiday day, for delivery the following day.

Please note that Next Day Delivery excludes these postcodes: AB31-56, BF (all), BT (all), FK17-21, GY (all), HS (all), IM (all), IV (all), KA (all), KW (all), PA20-80, PH (all), TR21-25, ZE (all)

Please see specific promotion Terms & Conditions for details BFPO Addresses We do ship to BFPO addresses (with Royal Mail) but for active combat zones there is a strict 2kg weight limit (as with all deliveries to BFPO addresses), so please take this into account when ordering. As a guide, with careful packaging we can just get away with a 1.6kg tub. All orders under this weight limit will be treated as standard UK orders. All orders over this weight will be priced incrementally according to their weight (£5 per 2kg increase). If you have any queries regarding a BFPO address, please contact our Customer Service Team who will be happy to assist with your order.

VITAMIN SUPPORT

Vitamin D3 is formulated to help you meet your daily intake of this essential vitamin, all in a convenient, easy-to-take tablet. Supplementing with vitamin D3 helps maintain normal muscle function, normal bone health, and supports a normal immune system.

IMMUNE HEALTH

Vitamin D contributes to normal function of the immune system

DAILY SERVING

1000 IU (25ug) Vitamin D per serving

OVERALL HEALTH

Vitamin D supports the normal function of the immune system

REDUCE DEFICIENCIES

Vitamin D deficiencies are very common, especially in winter

  1. Vitamin B1 & B2 contribute to carbohydrate conversion
  2. Vitamin B6 aids protein metabolism.

SUPPORT OVERALL HEALTH

Vitamin D is a fat-soluble vitamin that plays an important role in supporting overall health. It’s naturally produced by the body when the skin is exposed to sunlight, the UVB rays hit the skins receptor cells which triggers a chemical reaction and produces vitamin D3. It can also be obtained through food supplements.

Vitamin D deficiencies are very common, especially during the winter months.

WHY CHOOSE?

  • 1000 IU (25ug) vitamin D per serving
  • Vitamin D contributes to the normal function of the immune system
  • Vitamin D supports the maintenance of normal teeth and bones
  • Vitamin D deficiencies are very common amongst athletes
  • Supports overall wellbeing

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SUGGESTED USE

Consume 1 tablet daily with food.

FORMULATED BY SCIENCE

Vitamin D contributes to the normal function of the immune system and the maintenance of normal teeth and bones and has a role in the process of cell division.

 

THE SCIENCE

High training demands can put strain on your immune system which can impact your training and wellbeing. Vitamin D is shown to contribute to the normal function of the immune system.

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THE SCIENCE

Vitamin D is a lipophilic prohormone primarily synthesised endogenously through exposure to solar ultraviolet B (UVB) radiation. It can also be obtained in limited quantities from dietary sources. Vitamin D plays a critical role in calcium homeostasis and bone mineralisation. Emerging evidence also underscores the importance of vitamin D in skeletal muscle function. Studies have demonstrated that increasing serum 25(OH)D concentrations from insufficiency (<50 nmol/L) to optimal levels (>75 nmol/L) via Vitamin D3 supplementation (5,000 IU/day for 8 weeks) enhances sprint and jump performance.  

For individuals requiring an increase in serum 25(OH)D to support bone health, muscle function, and immune resilience, SiS Vitamin D3 provides a targeted and effective supplementation strategy.

 

References

1. Close et al (2013). Assessment of vitamin D concentration in non-supplemented professional athletes and healthy adults during the winter months in the UK: implications for skeletal muscle function. J Sports Sci, 31(4): 344 - 353.

2. Owens et al. (2015). A systems-based investigation into vitamin D and skeletal muscle repair, regeneration, and hypertrophy.  Am J Physiol Endocrinol Metab, 309(12), 1019 - 1031. 

3. Morton et al. (2012). Seasonal variation in vitamin D status in professional soccer players of the English Premier Leage. Appl Physiol Nutr Metab, 37(4): 798 – 802. 

4. Close et al. (2013) The effects of vitamin D(3) supplementation on serum total 25[OH]D concentration and physical performance: a randomised dose-response study. Br J Sports Med, 47(11): 692 – 696. 

5. Owens et al. (2017). Efficacy of high-dose vitamin D supplements for elite athletes. Med Sci Sports Exerc, 49(2): 349 – 356. 

 

 

 

 

Nutrition Overview Science