What is vitamin C deficiency?

Vitamin C is an essential vitamin, and if you don’t regularly have food that contains vitamin C as part of a healthy diet, you might become deficient in it.

If you are concerned about vitamin C deficiency, adding a fruit or vegetable that’s high in vitamin C to one meal every day might be a good idea. You could also try having an orange or mandarin as a snack.

For more information, read the healthdirect page on vitamin C and your health.

What are the symptoms of vitamin C deficiency?

If you have low vitamin C, you may notice that you feel generally unwell with nausea and a poor appetite. Some people with vitamin C deficiency report flu-like symptoms. This may be partly due to low iron levels since the absorption of iron is dependent on vitamin C.

A major vitamin C deficiency (consuming less than 7mg per day, which equates to around one segment of orange, for more than 4 weeks) can result in scurvy. This condition involves bone and blood vessel disease, bleeding in the hands and feet, and in extreme cases, death.

Your body uses vitamin C to build collagen — a key component of healthy skin. Vitamin C deficiency can make your skin more fragile, you may notice bleeding gums, and your hair may grow in bent or coiled shapes. Another sign of severe vitamin C deficiency is slow-healing wounds.

Am I at risk of vitamin C deficiency?

The Australian Government publishes a Recommended Dietary Intake (RDI) for all vitamins, which lists the amount of each vitamin you should aim to eat as part of a healthy diet.

Adults need around 45mg of vitamin C daily — this equates to around half an orange or a cup of strawberries. Breastfeeding women need a little more — around 65mg daily — while children need a little less, at around 30mg to 40mg daily.

An average-sized orange contains around 84mg of vitamin C.

People who are more vulnerable to vitamin C deficiency may include:

• fussy eaters
• elderly people
• people with disabilities
• people with alcohol and drug dependence or addiction
• people who can't afford enough nutritious food
• people with conditions that affect their diet such as those with eating disorders, depression or long periods of low appetite (for example, people with chemotherapy-induced nausea)
• people with health conditions that affect their ability to digest and absorb food, including chronic diarrhoea
• people who have had bariatric surgery
• people recovering from any surgery

Because vitamin C dissolves in water, boiling or steaming vegetables can reduce the vitamins available for your body to absorb from the foods you eat. Consider eating fresh fruit and vegetables, or lightly steam your vegetables, to improve their nutritional value.

If you are concerned that you may not be eating or absorbing enough vitamin C-rich foods, you may be at risk of vitamin C deficiency and a vitamin C supplement taken as recommended may be useful, but be sure to see your doctor or a dietitian first for advice.

What happens if I have too much vitamin C?

Vitamin C is water-soluble (dissolves in water) so even if you eat lots of foods that are rich in vitamin C, your body will only absorb what it needs. Any extra vitamin C you have in food or drink will pass naturally.

Excess vitamin C usually only occurs if you take high-dose supplements, which can result in nausea, stomach cramps, headaches, fatigue, kidney stones and diarrhoea. If you have diabetes, take special care not to overdose on vitamin C supplements, as too much of this vitamin may interfere with medical tests.

Read about vitamin C and your health to better understand how vitamin C affects your body.

If you think you are getting too much (or too little) vitamin C in your diet, speak with your doctor and ask for a referral to a dietitian for a comprehensive nutritional assessment.