Figures published by UK health and wellbeing provider Benenden Health show that over 100m health-related internet searches were made by British people in the past 12 months.
Anxiety, schizophrenia and chronic depression/bipolar came in the top 10 most Googled health concerns, making up one quarter of all health searches.
The research, which analysed more than 8,000 unique health-related phrases and questions, comes amid growing concern that people in the UK are turning to Google for self-diagnosis, rather than visiting their GP.
Sexual health-related searches were the second most commonly searched, with chlamydia, gonorrhoea and thrush also in the top 10.
GPonline revealed earlier this year that of the 307m GP appointments delivered over the past year by GPs in England, more than 211m - around seven in 10 - took place within a week.
But in around one in six cases (17.4%), patients waited more than two weeks for an appointment - reflecting rising pressure on general practice across England.
The BMA warned earlier this year that over 2m patients waited almost a month to get a GP appointment in January and February this year - up 15% from the same period in 2018.
The Benenden report suggested online self-diagnosis may be most common in London, the Midlands and north-west England, with London alone representing 23% of all searches.
BMA GP committee chair Dr Richard Vautrey said it was important people were using the right websites to check health issues.
‘With GPs delivering over 300m appointments a year I’m surprised these Google figures are so low. Many patients presenting in surgeries, regardless of waiting times, have often already checked their symptoms online and want to discuss them further with their GP,' Dr Vautrey said.
'The important issue is to encourage and enable patients to use reliable health websites,’ he added.
Prime Minister Boris Johnson said last month that he wanted to reduce GP waiting times, prompting a BMA warning that to do this would require efforts to tackle the underlying causes.
Dr Vautrey warned Mr Johnson he 'needs to firstly recognise the underlying pressures behind long waits and then spell out exactly how he is going to address these'. The GPC chair added: 'Without the staff to carry out consultations, patients will continue to wait too long.’