22% off €40
Shop now
Redeem instore | T&CsStore finderHelp Centre
Shop nowRedeem instore | T&CsStore finderHelp Centre
Basket

Explore related topics

Can you have too much vitamin D?

16/09/20266 min read

Laura Harcourt

Written byLaura Harcourt

hazel_clarke

Reviewed byHazel Clarke

Female looking at the sun
Can you have too much of the sunshine vitamin? Find out how much vitamin D is too much, the signs to look out for and how to supplement safely

Summary

1Where do we get vitamin D from?

Spending time outdoors with your skin exposed to direct sunlight is one way to get vitamin D, alongside eating vitamin D-rich foods or take a vitamin.

2Can you have too much vitamin D?

Yes, taking too much vitamin D through supplements can lead to vitamin D toxicity, although you can’t get too much from sunlight.

3Recommended daily amounts of vitamin D

It’s recommended that adults and children over the age of one need 10 micrograms (μg) of vitamin D per day.

Jump to section

Explore related topics

Vitamin D, commonly referred to as the ‘sunshine vitamin’, is an essential micronutrient that your body needs for healthy bones and muscle function. It also plays an important role in supporting your immune system, helping your body fight off bacteria and viruses.1 But when it comes to vitamin D, more isn’t always better.

You can’t get too much vitamin D from sunlight, and it’s very unlikely from food alone – but taking too much through supplements can lead to vitamin D toxicity. So, how much is too much and what signs should you look out for? Here's what you need to know.

Where do we get vitamin D from?

Most of our vitamin D comes courtesy of the sun. Spending time outdoors with your skin exposed to direct sunlight helps your body make the vitamin D it needs.2 That doesn’t mean skipping the sun protection, though – it’s still important to protect your skin from UV rays with an SPF of 30 or above.3


The catch? Here in the UK, sunshine isn’t always something we can rely on. Getting enough vitamin D can be tricky for some people even in the summer  – and becomes particularly difficult during the darker winter months. That’s why the NHS recommends taking a daily vitamin D supplement between October and late March/early April.4


For some of us, a seasonal top-up might not be enough. You may need to take a supplement every day, not just during winter, if you’re at higher risk of vitamin D deficiency.2-5 This includes people who:

  • are housebound 

  • have limited access to an outside space 

  • wear clothes that cover their arms and legs 

  • are pregnant or breastfeeding 

  • are  over 65 years old

  • have dark skin 

As well as getting your vitamin D from sunlight and supplements, you can get around 10% of your daily requirement from vitamin D-rich foods.6,7 Foods that contain vitamin D include:2,4,8

  • oily, fatty fish, such as salmon, sardines, trout, herring and kippers

  • red meat, especially beef liver

  • eggs – in particular, the yolks

  • mushrooms

  • fortified products, including certain cereals, plant-based milks and margarines

Can you have too much vitamin D?

You might be wondering 'can you overdose on vitamin D?'. While we all need vitamin D, it is possible to have too much. You can’t get too much vitamin D from sun exposure – although you still need to protect your skin from UV rays – and it’s very unlikely you’ll get too much through food alone. 2,4,6,7

The main risk comes from taking too much through supplements. Too much vitamin D in the body is known as vitamin D toxicity, or medically as ‘hypervitaminosis D’. It’s rare but can happen if you take excessive amounts of vitamin D through supplements.4,9 It’s very difficult to get more than 10% of your daily vitamin D requirement through food, which is why getting too much from food sources alone is unlikely.

So, how much vitamin D is too much? Adults (including pregnant and breastfeeding women, as well as the elderly), and children over 11 shouldn’t take more than 100μg (4,000 IU) of vitamin D a day.4 Children aged one to 10 shouldn’t have more than 50μg (2,000 IU) a day, while babies under one shouldn’t have more than 25μg (1,000 IU) a day.4

What’s the recommended daily dose for vitamin D?

How much vitamin D you need can depend on your age. Current advice recommends that safe vitamin D dosage for adults and children over one is10 micrograms (μg) of vitamin D per day. This helps keep bones healthy and support normal muscle and nerve function and immunity.4 Babies under one year old need a little less, at around 8.5–10μg per day, and some may need a supplement prescribed by their doctor.4 At the other end of the scale, adults aged 65 to 69 need 15μg per day, while those aged 70 and over need 20μg.8

Confused by all the numbers on your supplement label? In the UK, vitamin D is usually measured in micrograms (μg), but you might also see International Units (IU) on some supplement or food labels. They’re simply two different ways of measuring vitamin D.
Hand close up holding vitamin-d supplements
As a quick guide:
  • 1μg = 40 IU
  • 10μg = 400 IU
  • 100μg = 4,000 IU 8
So, if you're comparing products, check both the unit and the amount before taking them together.

What are the symptoms of too much vitamin D?

Taking too much vitamin D can lead to vitamin D toxicity (hypervitaminosis D), which can cause calcium levels in your blood to become too high – known as hypercalcaemia.9,10 Over time, this can weaken your bones and damage your kidneys and heart, so it’s important you avoid taking too much vitamin D.4  Symptoms of hypercalcaemia to look out for include:11,12 
  • vomiting 
  • nausea 
  • stomach pain 
  • feeling weak 
  • fatigue
  • constipation
  • confusion 
  • frequent urination 
  • excessive thirst 
  • mood swings 
Experiencing one or more of these vitamin D toxicity symptoms doesn’t necessarily mean you have vitamin D toxicity, as they can have many different causes. However, if you’re concerned about your vitamin D intake or any of these symptoms, speak to your doctor for advice.

Vitamin D FAQs

Should you take vitamin D all year round?

For most people, you don’t need to take vitamin D all year round. In the UK, the NHS recommends a daily 10-microgram supplement during autumn and winter, when sunlight isn’t strong enough for your body to make enough vitamin D.13 However, some people – including those who spend little time outdoors or have darker skin – are advised to take a vitamin D supplement throughout the year.13
 

Can you take vitamin D and calcium together?

Vitamin D and calcium can be taken together – the two actually work hand in hand to support bone health. However, that doesn’t mean everyone needs both supplements – it’s generally better to get enough calcium from food and use supplements only when needed.14

Taking more than one supplement? Find out why timing can matter when taking your vitamins and supplements.
 

How much vitamin D is too much?

For most adults, 100 micrograms (4,000 IU) of vitamin D a day is the upper safe limit (and not the target dose) – taking more than this can be harmful, particularly over time.13 Too much vitamin D can cause calcium to build up in the body, potentially damaging the kidneys, heart and bones.13
 

The final say

Vitamin D is essential for your health, but more isn't always better. You can't get too much from sunlight and it's very unlikely you'll get too much through food alone – the main risk of vitamin D toxicity comes from taking excessive amounts through supplements.

Our key takeaway? Check the amount on the label and don't exceed the recommended dose. If you take more than one supplement, remember to check whether vitamin D appears in each so you can keep track of your total daily intake. And if you're unsure about your vitamin D intake or whether supplementation is suitable for you, speak to your GP or another healthcare professional.

Not sure where to start? Take a look at our favourite vitamin D gummies or our best vitamin D supplements to try.
Disclaimer – This article provides informational advice and is not a substitute for medical care. Working with experts for accuracy, we take great care to ensure the information is up-to-date and relevant. However, you should always consult your GP or healthcare professional before using supplements or alternative products, particularly if you have medical conditions or are under supervision.

Sources

1. Centers for Disease Control and Prevention. Why Micronutrients Matter [Internet]. [cited 2024 May 16]. Available from: https://www.cdc.gov/nutrition/micronutrient-malnutrition/about-micronutrients/why-it-matters.html
2. The Association of UK Dieticians. Vitamin D [Internet]. [cited 2024 May 23]. Available from: https://www.bda.uk.com/resource/vitamin-d.html
3. NHS Choices. Sunscreen and sun safety [Internet]. 2024 [cited 2024 Jul 24]. Available from: https://www.nhs.uk/live-well/seasonal-health/sunscreen-and-sun-safety/
4. NHS. Vitamin D [Internet]. [cited 2024 May 23]. Available from: https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
5. Scottish Government. Vitamin D: Advice for parents [Internet]. [cited 2024 May 13]. Available from: http://www.gov.scot/publications/vitamin-d-advice-for-parents/
6. Better Health Channel. Vitamin D [Internet]. [cited 2024 May 23]. Available from: https://www.betterhealth.vic.gov.au/health/healthyliving/vitamin-d
7. National Institute for Health and Care Excellence. Vitamin D deficiency in adults [Internet]. [cited 2024 May 23]. Available from: https://cks.nice.org.uk/topics/vitamin-d-deficiency-in-adults/
8. National Institutes of Health. Vitamin D [Internet]. [cited 2024 May 23]. Available from: https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
9. Asif A, et al. Vitamin D toxicity. Treasure Island (FL): StatPearls Publishing; 2024. [cited 2024 May 23]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK557876/
10. Wawrzyniak A, et al. Structural and metabolic changes in bone. Animals (Basel). 2022;12(15):1946. https://doi.org/10.3390/ani12151946
11. Sadiq NM, et al. hypercalcaemia. Treasure Island (FL): StatPearls Publishing; 2024. [cited 2024 May 23]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK430714/
12. MSD Manual. hypercalcaemia [Internet]. [cited 2024 May 23]. Available from: https://www.msdmanuals.com/en-gb/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypercalcaemia 
13. NHS. Vitamin D - Vitamins and Minerals [Internet]. NHS. 2020 [cited 2026 Sept 8]. Available from: https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
14. Heravi AS, Michos E D. Vitamin D and Calcium Supplements: Helpful, Harmful, or Neutral for Cardiovascular Risk? Methodist DeBakey cardiovascular journal [Internet]. 2019 [cited 2026 Sept 8];15(3):207–13. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6822648/
 
Join Rewards for Life
Join Rewards for Life
Join rewards for life today and we'll give you 300 points worth €3.00
Find out more
|
Sign In
|
Speak to an Advisor
Speak to an Advisor
Book your free, one-to-one online consultation with one of our qualified advisors.
Help Centre
Help Centre
Need some help with an order or want to speak to a member of our Customer Services team?
Sign up for exclusive offers

Plus, get expert advice to support your health & wellness straight to your inbox when you sign up to Holland & Barrett emails.