Patients are expected to behave responsibily
Ministers have launched a constitution for the NHS in England which they see as effectively a "bill of rights" for the health service.
It sets out patients' rights to care and their responsibilities, such as keeping appointments.
However, the health secretary stressed it would not see the "broccoli police" visiting those neglecting their health.
Opposition MPs and some patient groups fear an opportunity may be missed to make the NHS more accountable.
The idea of the constitution, first suggested more than two years ago, is to produce a concise document which sets out what patients and staff should expect within the NHS.
Prime Minister Gordon Brown has said a constitution could secure the future of the NHS for many years.
The final version, to be unveiled in Parliament, is expected to state that patients have the right to access services predominantly free of charge, wherever possible convenient, free of discrimination and delivered in a professional manner, in a clean environment.
In return patients are expected to be asked to treat staff with respect, register with a GP, keep appointments, take part in vaccination programmes, and make a contribution to their own, and their family's, good health.
Health Secretary Alan Johnson told an audience at Westminster this was not intended to be used to bully patients who did not comply.
He said: "We have got a section on personal responsibilities but it's not something that's backed up by law - [you'll not] have the broccoli police come round if you are having a fry up.
A right to makes choices about care and to information to help exercise that choice
A new legal right to receive the vaccinations that the Joint Committee on Vaccination and Immunisation recommends
A right making explicit entitlement to drugs and treatments that have been recommended by NICE for use in the NHS
A right to expect local decisions on funding of other drugs and treatments to be made rationally following a proper consideration of the evidence
Clear and comprehensive rights to complaint and redress
"It was never meant to be something that changed the health service and made it less acceptable to people and made it problematic."
However, he dismissed accusations that the constitution would have no impact.
For instance, it would help to make patients aware of rights - such as access to drugs approved by the National Institute of Health and Clinical Excellence - of which they might not currently be aware.
"It is a really good thing to bring all this together in an accessible document and I think it will be interwoven into the life of the NHS in the future."
A spokesman for the Liberal Democrats said that while it was hard to disagree with the principle of an NHS constitution, it was too early to predict whether it would make a difference.
"This government risks missing a real opportunity to make the NHS more accountable to the people it serves," he said.
"The real test of the constitution will be whether it has had any meaningful effect in protecting and safeguarding the NHS and improving the experience for individual patients in 10 years' time."
The Conservatives have also expressed doubts that a constitution will help eradicate the "postcode lottery" in drugs and treatment, saying that it offers nothing new in terms of legal rights for patients.
The Patients Association said the document consisted largely of "optimistic pledges" without any real incentives for NHS managers to improve the service, or penalties for failure.
Director Katherine Murphy said: "We do not expect this document to make any difference to the care patients are receiving."
Dr Hamish Meldrum, British Medical Association chairman, said: "We need more than a "feelgood" document.
"In its current form, it is unclear how the constitution will change the everyday experiences of patients and staff."
Mike Sobanja, who chairs the NHS Alliance, which represents primary care trusts, said: "I think we should welcome the constitution as having real potential to enhance patient care - by patients being clear about their rights and responsibilities.
"What needs to happen now is for the NHS to 'walk the talk' and embrace the constitution in all other policies and implementation.
"If it remains a piece of paper, it won't help - action not words will bring it alive."
In Scotland a public consultation on a Patients Rights Bill has recently ended. The government will publish its response later in the year.