A poll of 2,000 adults found one fifth of the population fear catching flu because they have had the flu jab.
Worryingly, this false belief may be the reason why only 37 per cent of Brits are planning to be vaccinated against the virus this year.
Ten per cent falsely think going outside in the cold, especially with wet hair, can make you vulnerable to illness.
Jane Devenish, pharmacist at Well Pharmacy, which commissioned the research, said: “Being cold or having wet hair doesn’t give you flu.
“The only way to catch flu is by being exposed to the flu virus, and the virus peaks in winter.
“However, there is some evidence that having a lower body temperature can lower your ability to fight off viruses, so listen to your grandmother’s advice and wrap up warm.”
The study also revealed the two most common methods used by Brits to try to ward off flu are dosing up on Vitamin C, and drinking a ‘hot toddy’ – a warm whiskey drink with honey and lemon.
And people were equally confused about what to do when they were unlucky enough to get a bout of flu.
One in four think you should sweat out the fever, nearly a fifth believe you should starve it, and 16 per cent think the illness can be ‘cured’ by chicken soup.
Jane Devenish added: “There is no evidence that vitamin C prevents flu, and alcohol actually lowers your immune system, lowering your body’s ability to ward off viruses like flu.
“Sweating is the body’s natural way of lowering its temperature, and it’s important to reduce a fever by keeping cool and taking paracetamol.
“I would never recommend starving yourself.
"Chicken soup, like any fluids, is great for staying hydrated and nourishing your body which definitely helps recovery, but unfortunately nothing can really ‘cure’ flu.”
It also emerged despite the fact that 70 per cent of Brits surveyed via OnePoll.com had experienced flu, 53 per cent have no intention of getting the flu jab this year.
And of people less likely to get a jab this year than last, a third say it’s because they don’t believe it can protect against new strains like ‘Aussie’ or ‘Japanese’ flu.
Only 15 per cent of Brits have had a flu jab from a pharmacy, despite 65 per cent knowing it was possible.
But over half would be happy to do so in the future, to save a trip to the doctor’s surgery.
Jane Devenish added: “It’s concerning that so many people still believe that the flu jab gives you flu.
''The injected flu vaccine given to adults contains inactivated flu viruses, so it definitely cannot give you flu.
“The only way to prevent flu is to get the flu jab.
"Even if you are not vulnerable or high risk, you’re likely to come into contact with someone who is, and it may have serious health consequences for them.
“So, I would urge everyone to get the flu jab this year, and every year, to protect themselves and their loved ones.”
THE TOP 10 FLU MYTHS – TRUE OR FALSE?
1. A ‘hot toddy’ can help with flu symptoms: FALSE – alcohol lowers your immune system
2. You should sweat out a fever: TRUE – sweating is how the body naturally cools down a fever
3. Vitamin C can prevent flu: FALSE – the only way to prevent flu is with the flu jab
4. The flu jab can give you flu: FALSE – the viruses injected are inactivated
5. Starve a fever, feed a cold: FALSE – never starve your body
6. A bowl of chicken soup will help cure flu: FALSE – nothing can cure flu
7. Eating garlic can prevent flu: FALSE – garlic does have some anti-viral properties but there is no evidence that it prevents flu
8. Being outside in the cold can give you flu: FALSE – only the influenza virus gives you flu
9. You can catch flu by going outside with wet hair: FALSE – being cold or wet cannot cause flu
10. Antibiotics can cure flu: FALSE - antibiotics fight infections caused by bacteria, but the flu is cause by a virus. Taking antibiotics when you have a virus may do more harm than good.