For those who are scared of needles, it may be easier said than done.
But smiling and being happy when you go for an injection at the doctor could make it work better.
A study by Nottingham University found people who were happiest when they went for their autumn flu jab were better protected from getting ill.
That is because a good mood boosts the immune system, helping it to react properly to the tiny dose of virus in a vaccination.
Researchers found being in the right frame of mind on the day of an injection could cause the body to produce up to 14 per cent more antibodies, increasing the protection.
They even raise the possibility of doing yoga or watching a comedy film before going to the doctor.
A study has found people who were happiest when they went for their autumn flu jab were better protected from the virus (stock photo)
Professor Kavita Vedhara, from the university’s division of primary care, said: ‘Vaccinations are an incredibly effective way of reducing the likelihood of catching infectious diseases.
‘But their Achilles heel is that their ability to protect against disease is affected by how well an individual’s immune system works.
‘We have known for many years that a number of psychological and behavioural factors such as stress, physical activity and diet influence how well the immune system works and these factors have also been shown to influence how well vaccines protect against disease.’
Key findings
The results of the study are expected to apply to all routine vaccinations, but researchers looked only at 138 British pensioners given their seasonal flu jab.
Older people are the most vulnerable to flu and its complications, which is why they are offered the vaccination, but it works least well in this age group. It is estimated anywhere from 47 to 83 per cent of older adults are left unprotected despite being vaccinated.
Mood is believed to affect how well the injection works because our emotions and immune system are linked by the same pathways in the sub-cortical regions of the brain.
To test this, the researchers questioned people on how happy they were in the six weeks surrounding their injection and on the day itself. Then they calculated the injection’s effectiveness by measuring the amount of influenza antibody in the blood at four weeks and 16 weeks after the vaccination.
They found how someone felt on the day of the vaccination affected their protective antibody levels by between eight and 14 per cent.
Writing in the journal Brain, Behaviour and Immunity, the authors state that watching a comedy film and yoga have been found to boost people’s mood and immune response at the same time.
But they say it is unclear whether such ‘mood-enhancing interventions’ could be brought in by doctors given the short time periods of vaccination appointments.
Following the results, lead author Kieran Ayling said: ‘We would expect that similar effects may be true for all vaccines, especially in people with less effective immune systems such as the elderly. That is not to say that positive mood may be the only way to promote the effectiveness of vaccines.’
The team also measured physical activity, diet and sleep in the 65 to 85-year-olds but found these had no effect.