Vitamin deficiencies


Vitamins are nutrients our bodies need to stay healthy and work properly. These nutrients are found naturally in a healthy, balanced diet. When we don’t get enough of these nutrients, we can become ill You’ll find information here about vitamin D deficiency, vitamin B12 deficiency and folate deficiency.

Causes of vitamin D deficiency

The main causes of vitamin D deficiency are:

  • Not eating a healthy, balanced diet
  • Not getting enough sunlight. Our bodies naturally make vitamin D when our skin's exposed to sunlight

Symptoms of vitamin D deficiency

You may not notice any symptoms unless you’re severely deficient. However, if you’ve been deficient in vitamin D for many years, you’re at higher risk of developing diabetes, osteoporosis, kidney problems, and heart disease. If your vitamin D levels are very low, you may experience tiredness, weakness, and bone and muscle pain.

If you have vitamin D deficiency symptoms.

If you think you might have vitamin D deficiency, you should see your Doctor. 

Do I need a vitamin D supplement?

Our bodies naturally make vitamin D when exposed to the sun. However, we don't always get enough sunlight. For this reason:

  • Adults and children over five years old should consider a daily supplement containing 10 micrograms of vitamin D between September and March. Pregnant women in particular should ensure they're getting enough vitamin D
  • Children aged between one and four years old should be given a daily supplement containing 10mcg of vitamin D
  • Breastfed babies from birth to one year old should be given a daily vitamin D supplement
  • Formula-fed babies don't need a supplement as long as they drink more than 500ml of formula milk per day, as vitamin D is already added to formula milk
  • If you're very dark-skinned, don't spend much time outside, or usually wear clothes that cover your skin, you should consider a daily supplement containing 10 micrograms of vitamin D throughout the year

Your pharmacist can advise which supplement might be suitable. 

Symptoms of vitamin B12 or folate deficiency

Our bodies need both folate and vitamin B12 to make oxygen-carrying red blood cells, and to maintain a healthy nervous system.

If we're deficient (lacking) in either folate or vitamin B12, we risk developing anaemia.

The main symptoms of both these anaemias are:

  • Extreme tiredness
  • Pins and needles
  • A sore, red tongue or mouth ulcers
  • Muscle weakness
  • Disturbed vision
  • Feeling depressed or confused
  • Having problems with your memory, understanding and judgement

If you think you have vitamin B12 or folate deficiency 

If you have symptoms, see your Doctor straight away. Prompt treatment is important to help avoid long-term damage. Your Doctor will test to see if you're deficient in vitamin B12, folate, or both. 

One common cause of these deficiencies is a condition called pernicious anaemia, which requires ongoing Doctor treatment to supplement your vitamin B12 or folate levels. This condition affects your stomach, and means your body can't absorb B12. 

Other causes include restrictive diets. This can mean a fad diet, or a vegetarian or vegan diet undertaken without proper research and supplementation. Certain medicines can also affect your vitamin absorption and cause deficiencies. 

Another cause is heavy alcohol use. If you regularly drink alcohol, especially to excess, then reducing your intake to within the recommended limits (no more than 14 units per week for both men and women) could help to improve your symptoms. If you think you may be dependent on alcohol, talk to your Doctor. They'll be able to direct you to support and resources that may help you quit.

If your Doctor finds you have a deficiency, they may recommend a supplement, or changes to your diet or lifestyle. 

Do I need a vitamin B12 or folate supplement?

Most healthy adults can get the vitamin B12 and folate they need from a balanced and varied diet. If you're concerned your diet doesn't meet your nutritional needs, there's no replacement for eating well but you can consider a supplement. Your pharmacist can advise which one may be suitable. 

If you're pregnant or aiming to conceive, it is recommended that you take a daily supplement containing 400 micrograms of folic acid from the time you stop using contraception until the end of the 12th week of pregnancy. This can help to support your baby's healthy development.

Next steps

  • All adults should consider a daily 10 microgram vitamin D supplement between September and March
  • If you're aiming to conceive, or are pregnant, take a daily 400 microgram folic acid supplement from before conception until week 12 of pregnancy
  • If you have symptoms of a vitamin deficiency, see your Doctor straight away