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Vitamin D3 (3000 IU)

1 tablet per day


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

Click to Build Your Bundle - 5 Pouches for £23


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This Vitamin Supports

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


Each one-a-day tablet contains 3000IU of Vitamin D3.

Vitamin D blends are some of our most popular vitamin supplements, as they contribute 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 your healthcare practitioner advises. Do not exceed the stated daily intake. If you're unsure of your optimal dosage, look at our other Vitamin D supplements or contact our friendly team for 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.

Microcrystalline Cellulose, Dicalcium Phosphate Dihydrate, Magnesium Stearate, Anti-Caking Agent (Silicon Dioxide), Cholecalciferol.

Buy Vitamin D3 (3000IU) Tablets

Maximum strength Vitamin D3 supplements to give your body additional support

Vitamin D3, also known as cholecalciferol, plays several crucial roles in the body, primarily related to bone health, immune function, and cellular growth. This essential vitamin is usually created in the body during exposure to sunlight. While most people get enough D3 this way, others need support in the form of supplements.

Sealions' maximum strength 3000IU Vitamin D3 supplements are sourced from quality ingredients and give your body a powerful boost. We being affordability straight to your door at just £5.00 for a year's supply.

What is Vitamin D3?

Also known as cholecalciferol, D3 is different to other forms of vitamin D, as it's produced naturally in the skin through exposure to sunlight. When your skin is exposed to ultraviolet B (UVB) rays from the sun, it naturally synthesises vitamin D3. The amount of vitamin D, your skin makes depends on many factors, including the time of day, season, latitude, and your skin pigmentation.

Although few foods naturally contain vitamin D3, some good dietary sources include:

  • Fatty fish like salmon, mackerel, and tuna
  • Fish liver oils, which are among the best sources
  • Small amounts in beef liver, cheese, and egg yolks
  • Some mushrooms also provide vitamin D3 in variable amounts

If you don't see the sun much, or dietary restrictions mean a varied and balanced diet isn't possible, Vitamin D3 3000IU tablets offer a range of benefits.

Who should take Sealions Vitamin D3 (3000IU) tablets?

Our 3000IU Vitamin D3 tablets are powerful food supplements that support numerous functions in the human body. This higher dose is particularly beneficial for people who have limited sun exposure or dietary intake. Our supplements can be particularly important for individuals living in northern latitudes, during the winter months, or for those who have dietary restrictions that limit their intake of foods rich in vitamin D3:

Limited exposure to sunlight

People in the Northern Hemisphere are more prone to lacking vitamin D3 during the winter because of the little sunlight. Even though there is sunlight in winter, research shows it doesn't contain the right amount of what our skin needs to synthesise it, so supplementing can help you maintain optimum vitamin D3 levels.

Age and genetics

As the skin ages, it's harder to produce sufficient vitamin D3 from sunlight alone, and supplementation is central to supporting normal function. People with darker skin tones can also struggle with reduced vitamin D3 levels due to higher melanin levels.

Medical conditions

Certain medical conditions can prevent the body producing enough vitamin D3, including Coeliac Disease, Chron's Disease, and those who fall into the morbidly obese category.


As animal-derived food sources containing D3 aren't available to vegans or vegetarians, 3000IU vitamin D3 tablets are an excellent food supplement that allow you to enjoy a healthy lifestyle and not suffer for it.

The benefits of taking 3000IU vitamin D3 tablets

Taking 3000IU vitamin D3 tablets can offer several health benefits, especially if you have low vitamin D levels, or are at risk of deficiency. It's important to note that the recommended daily intake can vary based on age, health status, and your individual needs.

Some potential benefits of taking this dosage include:

Immune system boost

A healthy immune system is vital to prevent infections and help you battle bacteria when it enters your body. Many people struggle to maintain their immune system, but vitamin D3 can promote its normal function.

Regular doses can power up your white blood cells and give them extra support when dealing with infections.

Bone health

While calcium is central to maintaining normal bones and teeth, vitamin D3 is crucial for ensuring your body absorbs calcium efficiently. Many people combine D3 3000IU tablets with calcium to reap the maximum rewards.

Taking one tablet a day can have an impressive impact on your bones and even prevent osteoporosis.

Normal muscle function

One of the most prominent signs of vitamin D3 deficiency is muscle pain and weakness - especially in older people. However, taking a supplement ensures better muscle function, which promotes balance and strength. Older people are more at risk of falls, so our supplement can serve as extra support.

People who work out regularly might experience quicker muscle repair when they take a supplement, as D3 supports muscle contraction.

Mental health and emotional wellbeing

According to Heed Life, vitamin D3 can have impressive mood-boosting benefits - especially for individuals with current mental illnesses, including depression, anxiety, and seasonal affective disorder (SAD). Low moods can worsen in the winter months, but taking a supplement can boost them.

Support for chronic illnesses

While there's limited research on vitamin D3 and its ability to support people with diabetes, some studies suggest improves insulin sensitivity. The sunshine vitamin might also have a role in preventing colorectal cancers, but this research is still ongoing.

Are Vitamin D3 3000IU tablets a good idea?

Our ultra vitamin D 3000IU tablets are high strength because they deliver a powerful dose of what your body needs. Plus, tablets at this strength ensure normal absorption of cholecalciferol, allowing you to reap the benefits.

  • Reversing deficiency: Higher doses of D3 play a remarkable role in treating deficiencies and boosting levels to the recommended amounts.
  • Better absorption: If a medical condition impacts your ability to absorb nutrients, our vitamin D supplementation will power up your immune system. Lower-strength amounts might not offer the same benefits.
  • Convenience: Our high-dosage D3 tablets are ultra-convenient; you only need one daily. If you hate taking pills, these are small enough for even the fussiest people.

Our supplements are considered safe for adults, but if you're under medical supervision, it's a good idea to seek support from your health professional before taking them. Pregnant and breastfeeding women should also consult with a doctor or pharmacist.

Why buy 3000IU Vitamin D3 from Sealions?

Sealions is on a mission to help everyone get essential vitamins and nutrients they might miss from a varied and balanced diet. Our supplements are formulated to offer all the support you need, without costing the earth.

Cost-effective supplements

How are our supplements so cheap when other food supplements cost a fortune? Well, it's simple; instead of taking a huge profit margin for ourselves, we pass the savings on to you. You get all of the high quality at a low price.

Sustainable solutions

Too many supplement providers pollute the environment with their unsustainable ingredients and packaging choices. Our products come in fully recyclable or compostable plastic packaging, so you don't have to worry about your carbon footprint.

Dedicated customer service team

We want you to have a great shopping experience and go out of our way to give you good value with each product. Our customer service team is always on hand to answer your questions, so please feel free to contact us.

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 75µg / 1500%

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.