Vitamin C seems to have remained under the radar in discussions over recent years about taking supplements, with other vitamins and minerals having received more attention, such as vitamin D and magnesium.
Pharmacist and herbalist Gerald Quigley says many people assume that if they “eat an orange or have an apple a day” they’ll receive their daily requirement of vitamin C, but the natural antioxidant is one of the “underrated” essential nutrients within the vitamins, minerals and supplements (VMS) space.
The issue, he suggests, is that given we don’t typically get fruit directly from trees or vegetables from the ground, we may not really know how much vitamin C we’re actually consuming.
Consuming the required amount of vitamin C has many health benefits, with “probably 50 different things that vitamin C plays a role in”, Mr Quigley says.
“For instance, there’s bone and teeth growth, collagen synthesis, healthy teeth and gums, excretion of heavy metals,” he said. “It promotes vasodilation … and wound healing. It regulates cholesterol metabolism, and it’s an essential co-factor in a whole range of immune regulatory mechanisms … It plays a very important role in reducing the risk of a lot of cancers as well.”
Dietitian, nutrition consultant and Dietitians Australia media spokesperson Joel Feren added: “Vitamin C is an antioxidant that helps protect cells against damage, maintains healthy skin, blood vessels and gums, and assists with wound healing.”
Sources of vitamin C
Mr Quigley says the main sources of vitamin C are fruit and vegetables, including broccoli, Brussels sprouts, citrus fruits, pineapple, potatoes, cabbage, strawberries, sweet potatoes, and tomatoes.
“You name it – if it’s fresh, it will have some vitamin C,” he said.
Mr Feren adds to the list of top food sources of vitamin C red capsicum, cantaloupe, kale, kiwi fruit, lychees and berries.
While fruit and vegetables are great sources of vitamin C, Mr Quigley says people don’t always consume an adequate amount of these daily.
He says a significant number of Australians aren’t consuming enough vitamin C-containing foods to meet their requirements, pointing to a survey from the Australian Institute of Health and Welfare indicating that “92 per cent of Australians don’t get the recommended intake of fruits and vegetables”.
Aside from inadequate dietary intake, Mr Quigley says some medications can lead to vitamin C deficiency.
“Certain [medications] drive vitamin C out of the body, like diuretics, which can lower your levels of vitamin C,” he said. “The contraceptive pill lowers your levels of vitamin C.”
Also at risk of vitamin C deficiency, according to Mr Feren, are “people who abuse alcohol, smokers, malnourished seniors, infants with poor fruit and vegetable intakes, and individuals with eating disorders”.
Signs of vitamin C deficiency
Mr Quigley says signs indicating a person may not be consuming enough vitamin C include loss of appetite, diarrhoea, shortness of breath, fever, irritability, anaemia, poor wound healing, dry eyes, poor skin integrity and dry skin, bleeding gums and frequent cold and flu infections.
“Vitamin C plays a very important role in immune function,” he said. “It’s not the only thing, but it does play a very important role.”
Referring to the role of vitamin C in skin structure, Mr Quigley says 1000mg of vitamin C a couple of times a day will result in skin improvements. He adds that “those who find wound healing is very slow, or those with ruptured blood vessels, people with blood noses, people with haemorrhoids” would benefit from considering their vitamin C consumption and ensuring adequate intake.
Mr Feren agrees that clinical signs of vitamin C deficiency include bleeding gums, dry skin, and flu-like symptoms, while he adds dry hair to the list.
The role of VMS
Vitamin C deficiencies, however, “are very rare in Australia”, Mr Feren says.
“Vitamins, minerals and supplements are only necessary to correct deficiencies or to supplement inadequate intake,” he said.
“Nevertheless, some research shows that higher levels of vitamin C intake may assist with immune health and skin integrity. In any case, one should proceed with caution as high intakes of vitamin C [derived from supplements] can cause tummy upset and nerve damage.
“Following a food-first approach and prioritising a wholefood diet that ensures an adequate intake of all the essential vitamins and minerals is the gold standard approach.”
Low C linked to cognitive impairment
Although, as Mr Feren says, vitamin C deficiency is uncommon in Australia, some sections of the population, as mentioned, are more at risk, including older Australians, especially those who are hospitalised.
Associate Professor Yogesh Sharma from Flinders University’s College of Medicine and Public Health is the lead author of a recent study that looked at links between cognitive impairment among older hospitalised Australians and low vitamin C levels.
“Given we know vitamin C deficiency is common among older hospitalised patients, medical professionals need to remain vigilant for this condition and confirm a patient’s vitamin C status in suspected cases,” he said.
“Previous research has shown that vitamin C plays a significant role in the functioning of the brain, with studies finding that vitamin C deficiency may be associated with cognitive impairment, depression and confusion.”
Looking at 160 patients aged over 75 admitted to the Geriatric Evaluation and Management Unit at the Flinders Medical Centre in Adelaide, the research team assessed their cognitive function and vitamin C levels.
A total of 91 patients were found to have cognitive impairment, while 42 were found to be vitamin C deficient with a blood level of less than 11mcmol/lt, below which point the rare disease of scurvy could develop.
“Our findings showed that cognitive function scores were significantly lower among patients who were vitamin C deficient, with further analysis suggesting vitamin C deficiency was almost three times more likely to be associated with cognitive impairment after adjustment for other factors,” Associate Professor Sharma said.
The study also found that symptoms associated with scurvy were likely to be present among patients with or without vitamin C deficiency. Many of these symptoms of vitamin C deficiency are common in older people, who may have bleeding, bruising and skin issues due to a number of other conditions.
“It may, therefore, be difficult to diagnose vitamin C deficiency solely on looking for these particular symptoms in older hospitalised patients,” Associate Professor Sharma said.
While the study doesn’t prove that vitamin C is a direct cause of the cognitive impairment, it has demonstrated that vitamin C deficiency is common and is associated with cognitive impairment in older hospitalised patients.
“Further studies will be needed to confirm this link, and then we can look to establish whether vitamin C replacement may be beneficial in prevention or reversal of the cognitive impairment,” said the study’s co-author, Professor Campbell Thompson from the University of Adelaide.
To view the Flinders University study, visit: mdpi.com/2076-3921/11/3/463
This feature was originally published in the November issue of Retail Pharmacy magazine.
