A common long-term symptom of Covid-19 is a loss or altered sense of smell and taste.
These complaints can last much longer than the virus itself, staying in place even when patients are testing negatively.
Research is still ongoing as to exactly how many people experience loss of smell as a result of Covid, but it’s known to be an early sign that you should get tested.
A 12-week trial is about to begin testing whether vitamin A nasal drops can help regain the sense of smell.
Here’s all we know about vitamin A and how it can help with these symptoms.
Why do people lose their sense of smell after contracting Covid?
It's estimated that roughly 86% of people who have Covid-19 lose some of all of their ability to smell, with the majority of people who did contracting a mild form of the disease.
Scientists don’t fully understand why this is, but have hypothesised that patients with milder forms of the virus may have higher levels of antibodies that restrict it from spreading to the nose.
Researchers also say that it could be due to there simply being a larger number of milder cases.
The majority of people regain their sense of smell within three weeks of recovering from the virus itself, but nearly 25% of affected people have reported still having limited or no sense of smell more than 60 days after first noticing it.
Why does vitamin A help with changes to the sense of smell?
Known as the Apollo trial and conducted by the University of East Anglia, the upcoming experiment is picking up on research from Germany that showed the potential benefit of the vitamin.
It’s thought that applying vitamin A drops to the nose can help to repair tissue in the nose that has been damaged by the virus.
The study is funded by the National Institute for Health Research and will see patients receive either a 12-week course of vitamin A nasal drops or inactive drops.
Brain scans from before and after the twelve weeks will be compared to see the effects of vitamin A on the damaged tissue.
Participants can still sign up to the study by being referred to The Smell and Taste Clinic at the James Paget Hospital. Recruitment will begin in December this year.
What foods contain vitamin A?
Although this trial is specifically examining how vitamin A works as a nasal spray, the vitamin can also be found in certain foods.
Also known as retinol, common sources of vitamin A include cheese, eggs, oily fish, milk, yoghurt, and liver products.
Your body will also convert beta-carotene into vitamin A when consumed.
Sources of beta-carotene include yellow, red, and green leafy vegetables, such as spinach, carrots, sweet potatoes, and red peppers, and yellow fruit, like mango, papaya, and apricots.
There is no evidence yet to suggest that eating vitamin A will have an effect on a loss or altered sense of smell.