How Much Vitamin D Per Day

How much vitamin D per day you need depends on multiple factors such as age, diet, and body weight. Adults need approximately 10μg per day of vitamin D to support their health. Learn more about dosage, testing & how to improve intake. 

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What Are the Signs of Low Vitamin D?

Without sufficient intake of vitamin D, you may be at risk of vitamin D deficiency. Insufficient levels may cause symptoms which are detrimental to your health. These signs of low vitamin D include:

  1. Constant coughs and colds
  2. Aching bones
  3. Weak muscles
  4. Unbalanced mood or feeling low
  5. FatigueHair loss
  6. Reduced wound healing

In order to get enough vitamin D per day to avoid these symptoms, you may wish to consider vitamin D supplements to support your dietary intake.

How Much Vitamin D Do You Need Per Day?

Your body needs a certain level of vitamin D per day to support the vital processes this nutrient carries out in your body.

According to the NHS:

 Group How Much Vitamin D Per Day? (μg - micrograms)
Infants (Up to 12 months) 8.5
Children (1-17 years) 10
Adults (18+ years) 10


Women, those pregnant and breastfeeding, and men, all need 10 micrograms of vitamin D per day. Vitamin D is very important during pregnancy to help support the healthy growth of your little one, and support your health during this special time.

Sometimes the amount of vitamin D is expressed as International Units (IU), where 1µg is equal to 40 IU. Therefore, a daily supplement of 10µg is equal to 400 IU.

Sourcing Vitamin D From the UK Sun

Only 10% vitamin D intake comes from food sources, because sunlight is the key source. Additionally, during October to March, we are unable to synthesise vitamin D from sunlight in the UK due to the low UVB levels from the sun. Therefore, government advice is that everyone should consider taking a daily vitamin D supplement during the autumn and winter.

Though many of us live more indoor lives than we may have used to, the NHS suggests that the majority of people should be able to make all the vitamin D they need from sunlight on their skin from March/April, making vitamin D a vital winter vitamin.

Can You Test If You Have Enough Vitamin D Per Day?

Fortunately, there is a way to identify if you are obtaining enough vitamin D per day. Whether through your diet or supplements, a simple blood test can determine your levels of the nutrient. Therefore, helping you identify if you need to increase your intake.

Testing for vitamin D deficiency can be straight-forward and can be completed from the comfort of your own home. The test identifies the stored D3 and D2 levels in your blood, to indicate whether you are getting enough vitamin D per day, and help support your body to see the benefits of vitamin D.

If you are concerned about deficiency, or whether you are getting enough vitamin D per day, you should consult your doctor. They may arrange a blood test for you.

Support Vitamin D Intake with Supplements

Only minimal amounts of vitamin D can be sourced from your diet, but you can help to support your levels with our vitamin oral spray supplements. Our range of vitamin D oral sprays provide different strengths tailored for different ages.


Vitamin D Dosage

Who Is It For?

Vitamin D 4000IU 

4000 IU / 100μg


Vitamin D 3000IU 

3000 IU / 75μg


Vitamin D 1000IU

1000 IU / 25μg

Teens/ Adults

Vitamin D 400IU Junior

400 IU / 10μg


Vitamin D 400IU Infant

400 IU / 10μg


Vitamin D 1000IU Vegan Spray

1000 IU / 25μg (vegan D3V®)


Since sunlight is the key source, you may not be able to get enough vitamin D per day, and need supplements to support your intake.

Who Is Most At Risk of Deficiency?

Some people may be more likely to struggle to absorb vitamin D than others. People within the Department of Health’s “at-risk” groups should strongly consider checking to see if they are getting as much vitamin D per day as they need, because they have an increased risk of deficiency:

  • People who are pregnant or breastfeeding
  • Infants and young children under 5 years of age
  • Older people aged 65 years and over
  • People who have low or no exposure to the sun
  • People who have darker skin

Those following a plant-based diet may miss out on the food sources of vitamin D because it is most frequently found in animal products, e.g. fish, eggs, dairy.

Taking Too Much Vitamin D Per Day

It is possible to take too much vitamin D per day, and be in a state of “vitamin D toxicity”. Therefore it is important to adhere to safe upper limits and Nutrient Reference Value (NRV) guidelines to avoid taking too much vitamin D per day.

  • Adults should not have more than 100 µg (4,000 IU) per day - taking more than this per day could be harmful in the long term.
  • Children aged 1 to 17 years should not have more than 50 µg (2,000 IU) a day.
  • Infants under 12 months should not have more than 25 µg (1,000 IU) a day.

Too much vitamin D per day can lead to a buildup of calcium in the blood, because the vitamin helps your body absorb calcium. Too much calcium in the blood is known as hypercalcemia, which can cause nausea and vomiting. If your levels remain too high, you may experience bone pain and kidney problems, as well as calcium stones.

Supplementing with BetterYou

At BetterYou, we combine nutritional supplementation and our sustainability mission. From our magnesium supplements to our sleep supplements, we use packaging made from plant-based plastic.

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