The vast majority of MPs said they had no desire to be prime minister
Almost a quarter of MPs would not enter politics if they were starting a career now, a poll for the BBC suggests.
Of those questioned, two-fifths said their work had left them feeling depressed and 84% said the public did not generally understand their job.
The survey of 132 MPs, for BBC Two's The People's Politician, found 86% thought voters did not give them a fair hearing over parliamentary expenses.
More than 140 MPs have announced they are standing down at the next election.
Many have done so in the wake of the expenses scandal of last summer, which exposed the claims made and left some politicians open to ridicule and scorn.
Researchers for the ComRes polling company found that 23% of the MPs it interviewed would not now choose to go into politics.
Some 37% said they had little or no power and 72% said the election would do nothing to neutralise the impact of the expenses scandal on the public.
Almost a third - 31% - said they had sometimes felt like quitting, 33% that they had lost sleep and 9% that they had feared they could not cope.
Meanwhile, 76% agreed that voters' expectations were "inconsistent and contradictory" and four-fifths agreed they were "hate figures".
Moving on to the health implications of the job, almost four in 10 MPs said they "always" or "often" exceed the government's recommended weekly alcohol limit.
However, 58% of those questioned said they got "a lot" of satisfaction from their work and 21% said they could not imagine being happier doing anything else.
While 14% said they aspired to be prime minister, none was confident they would be - and 84% said they had "no desire" ever to be PM.
The People's Politician programme will feature six politicians who are standing down at the election, including former Conservative leader Michael Howard, former shadow home secretary Ann Widdecombe and former Sports Minister Richard Caborn.
ComRes surveyed 132 MPs between 18 January and 7 February, but not all of them answered every question. Percentages relate to the number responding to each question.
The People's Politician will be broadcast by BBC Two at 2100 GMT on Thursday 18 March.