It’s the season of coughs and sneezes, but will daily vitamins help fight off the symptoms of flu, the common cold – and even Covid.
There are numerous supplements and remedies promising to prevent and alleviate common cold symptoms - including immune boosting vitamin C.
But it may not be the silver bullet remedy you have been led to believe.
Linus Pauling, renowned Nobel Prize winning scientist, is responsible for the claim vitamin C could prevent the common cold. But experts now say he relied on anecdotal evidence to promote these claims.
In fact, much of the evidence on the role of daily vitamins on the common cold is “inconclusive,” Dr Leyla Hanbeck, chief executive of the Independent Pharmacies Association told the Independent.
“Whilst some research has demonstrated that there is no link between taking these supplements when having a cold and shortening the cold symptoms, there are some studies that have shown these supplements play a role in managing the symptoms,” she said.
Vitamin C helps to repair tissue in the body and supports the immune system by protecting cells from free radical damage and enhancing the body's natural defences. Some studies suggest it also shortens a cold.
One review published in the American Journal of Lifestyle Medicine in 2016, found taking vitamin C, consumed at doses above 0.2 g/day could “decrease severity and duration” of a cold.
In a separate review published in 2023, researchers from the Australian National University and the University of Helsinki found vitamin C also reduced the length of a cold.
But the NHS says there's little firm evidence vitamin C prevents colds or speeds up recovery.
Another study by researchers at University of Helsinki did not find vitamin C to have a consistent effect against common colds.
There is “no value of vitamin C for common cold,” Professor Paul Hunter, epidemiologist at the University of East Anglia told the Independent.
“Part of the problem is there are quite a lot of passionate believers in the effectiveness of and promoting their preferred vitamin or supplement. However, the real evidence is much weaker if present at all,” he added.
However, maintaining a healthy immune system by eating vitamin rich foods could help you prevent getting ill in the first place.
“Vitamin D, C and Zinc boost the immune system when you have this regularly in your diet or complement your diet with supplement,” Dr Hanbeck said.
“It’s important to have a balanced diet and to ensure regular and sufficient levels of these vitamins because they play a role in strengthening the immune system and in turn help the body be better prepared against viruses,” she added.
Zinc doesn’t prevent colds but may reduce duration of ongoing colds, researchers of a 2024 Cochrane review concluded.
However, zinc is naturally found in red meat and dairy products and most people can get all the zinc they need from their diet alone.
There could be more hope for vitamin D - the sunshine vitamin which helps to keep the immune system in shape. But that’s only for people who are deficient, a 2021 Lancet review suggested.
The National Institute for Health and Care Excellence (NICE), which provides health advice and guidance to the NHS, said vitamin D could play a role in the immune system's response to respiratory viruses including the common cold. The NHS also advises taking a vitamin D tablet each day during the winter months.
The common cold typically causes a runny nose, a mild cough and sneezing, while the flu is a respiratory infection that can be far more debilitating causing aches and fevers.
Covid is another respiratory infection that can cause serious illness in vulnerable groups. It can cause cold-like symptoms, such as a runny nose, sore throat or blocked sinuses, as well as, chills and a persistent cough.
While there is no vaccine for the common cold, those aged 75 and over, those with a weakened immune system, and residents in older adult care homes, are entitled to a Covid vaccine, which can help reduce the severity of illness. There is also a flu jab available for people aged over 65, with long-term health conditions or who are pregnant.
