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Vitamin D3 (1000 IU)

1 tablet per day


Vitamin D is an extremely important vitamin that helps to support a healthy immune system.…
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  • days supply
  • compostable
  • 1.37p/tablet
  • vegetarian



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This Vitamin Supports

  • bones teeth
  • brain
  • eye health
  • immunity
  • joints
  • muscles


Each one-a-day tablet contains 1000IU of Vitamin D3.

Vitamin D contributes to the normal function of the immune system, normal muscle function and the maintenance of normal bones and teeth. 

Vegetarian Friendly


Swallow one tablet daily, with food or as advised by your healthcare practitioner. Do not exceed the stated daily intake.Unsure if you're buying the right dosage? Take a look at our other Vitamin D tablets or contact us if you need support. 


Food supplements should not be used as a substitute for a balanced and varied diet and a healthy lifestyle. Not suitable for children under the age of 12. If pregnant, breastfeeding or on medication, please consult a health professional before use. Discontinue use and seek medical advice if adverse reactions occur.


Store in a cool, dry place out of the sight and reach of children. For best before end date, see product.

Calcium Carbonate, Microcrystalline Cellulose, Magnesium Stearate, Anti-Caking Agent (Silicon Dioxide), Cholecalciferol.

Buy Vitamin D3 (1000IU) Tablets

Vitamin D3 (cholecalciferol) - also known as the sunshine vitamin - is an essential vitamin. While some people can absorb it through direct sunlight and a healthy diet, a vitamin D food supplement means your body gets all the beneficial effects daily, even when the sun isn't shining.

The many benefits of Vitamin D3

Vitamin D3 (calciferol) is a powerful vitamin with numerous benefits for your mind and body. While the body can absorb it naturally through exposure to sunlight, any people find they don't get enough during the winter months.

Taking vitamin D food supplements supports your body, helping it function normally, delivering various health benefits, whatever the weather.

Healthy bones

Vitamin D2 contributes to the growth of normal bones, as it promotes the normal absorption of calcium, which results in normal teeth and bones.

Using the recommended dosage to ensure the maintenance of normal bones also works to prevent conditions like osteoporosis and rickets, as you can enhance bone density.

Mental wellbeing

While there's no conclusive evidence that Vitamin D3 can reduce the symptoms of mental health issues such as depression, some studies due highlight that it has a positive effect on people.

Research published by Neuroscience News shows that children who get enough vitamin D in childhood are less likely to struggle with anxiety and low moods later in life.

Immune system support

The immune system is complex, but Vitamin D3 contributes to its functioning. A daily dose of vitamin D can boost the positive effects of macrophages and monocytes and their pathogen-fighting mechanisms.

By ensuring the normal function of the immune system, you can reduce the risks of certain chronic diseases, including autoimmune conditions.

Muscle function

Studies from Harvard Health have revealed that low Vitamin D levels contribute to insufficient muscle strength. Normal muscle function is central to ensuring you can perform daily activities and enjoy an active lifestyle, making our supplements beneficial for mobility.

Muscles also burn calories better than fat, making them instrumental for weight loss and maintaining a lean body.

Inflammation and diabetes management

Inflammatory conditions can prevent you from enjoying a healthy lifestyle, but Vitamin D3 can boost your immune system, and its anti-inflammatory properties benefit a range of conditions, including arthritis.

However, it can also play a significant role in insulin management, and one tablet daily could help you manage the condition more effectively.

Kidney function

The kidneys are essential organs that require various nutrients to function correctly. Vitamin D3 is instrumental in promoting kidney health because it can promote normal blood calcium levels. Some people also use it to treat and slow down the progression of kidney disease.

Shopping with Sealions gives you access to a range of benefits

Sealions is a supplement provider with a difference. You've probably seen vitamins and minerals that cost around £30 a month, but we ensure our customers don't have to worry about budgeting for their health.

We keep our prices low so you can benefit from the powerful active ingredients of Vitamin D3 (1000iu) and get your daily dose of direct sunlight - even in the coldest months.

Your health should never come at significant costs and compromises, so we lower our margins to give each customer fantastic savings. Instead of spending a fortune on a Vitamin D supplement, you can get 365 tablets for just £5.00

However, there are also other incentives to make Sealions your chosen supplement provider.

Quality first

Our supplements are sourced from high-quality ingredients, giving them healing properties. Shopping with us means you save money and don't have to worry about whether you're getting enough Vitamin D. Those sun-free winter months just got a whole lot brighter.

A sustainable solution

A negative in the supplement industry is the extensive use of single-use plastics. However, we take our environmental commitment seriously and work hard to ensure our supplements don't hurt the planet.

All of our products come in fully recyclable plastic packaging, making it the best choice if you want a convenient way to get your Vitamin D3 without worrying about your carbon footprint.

Shop with Sealions today

From better bone health or organ functioning to ensuring the normal absorption and utilisation of calcium, our Vitamin D3 supplements are a proactive step to enhancing your overall health and wellbeing.

With speedy UK delivery and a dedicated customer service team, shopping with us means you get supreme quality for a fraction of the cost other supplement providers charge.

If you'd like some support or advice, please don't hesitate to contact our friendly team. We're on hand to offer advice and support.

We offer four different shipping options for our customers in the UK, ranging from Free delivery to next day.

  • Standard delivery or Royal Mail from £1.49
  • Premium delivery from £2.49
  • Express delivery from £4.95
  • Scottish Highlands and Islands, Isle of Man and the Channel Islands from £4.99

Spend £20 or more and your order will qualify for FREE shipping.

We do our very best to process and dispatch orders on the same day when placed before 11.00am Monday-Friday.

Orders placed after this, may not be processed until the following working day (i.e. orders placed after this point on a Friday or over the weekend will be processed on the Monday [excluding Bank Holidays]).

For the full list of rates and locations we ship to please click here.

Full Nutritional Information

Per 1 tablet / %NRV*
*Nutrient Reference Value
**No NRV Established

Vitamin D3 25µg / 500%

Frequently Asked Questions (FAQ)

  • Why are Sealions vitamins so cheap?
    • All our Sealions products are on par with the quality of other major vitamin and supplement market leaders. We just do things differently here. We believe our customers should not have to front the standard high margins of vitamin products. Instead, we half our own margins, cut out the middle people and their high margins. End result? Quality vitamins at affordable prices for everyone. Happy days!

  • Where are Sealions products manufactured?
    • We source our ingredients from international and UK suppliers, and manufacture all our supplements here in Manchester, United Kingdom. Guaranteeing the products we make are of top quality for you and your family.

  • When/how should I take my Sealions vitamins?
    • Take one tablet/softgel per day, with food or as advised by your healthcare practitioner. Do not exceed the stated daily intake.

  • Which vitamins are Vegetarian?
    • All our vitamins are vegetarian except for Cod Liver Oil, Fish Oil, Glucosamine Sulphate and Evening Primrose Oil vitamin products.

  • Which Vitamins are Vegan-Friendly?
    • The following vitamin products are vegan-friendly: Ashwagandha Gummies, Charge Up Gummies, Night Time Gummies, Sesame Street Kids Multivitamin Gummies, Turmeric, Folic Acid 400µg, Green Tea Extract, Lactobacillus Acidophilus Probiotic 500 million CFU, Vegan Protein Powder, Vitamin B-Complex, Vitamin C (200mg), Vitamin C Orange Chewables (200mg), Vitamin K2 100µg, Vitamin B12, Iron, Vitamin C (500mg), Magnesium + B6, and Zinc.

  • Where should I store my vitamins?
    • Store your vitamin products in a cool, dry place out of direct sunlight and out of sight and reach of children. 

  • How many vitamins are in each pouch?
    • Our vitamins come in varying supplies ranging from 30 days all the way up to 365 days worth of vitamins, and you usually take one tablet/softgel per day. For our gummies range we recommend to chew two gummies daily.

  • Why can’t I just take vitamins and not eat nutritious food?
    • Vitamin and supplement products should not be used as a substitute for a balanced and varied diet and a healthy lifestyle.