Bunions are very common. They are more common in older people and in females.
The exact prevalence is hard to determine as different research will use different criteria to define just what a bunion is and/or how much the big toe is in valgus.
However, it is assumed that about almost 1/3rd of the population have a bunion of some degree or another. This study reviewed 78 published papers and pooling the prevalence estimates for hallux valgus reported that the prevalence was 23% in adults aged 18-65 years and 35.7% in elderly people aged over 65 years. Prevalence was higher in females (30%) compared to males (13%).
