Jeremy Hunt has reject Professor Stephen Hawking's allegation that he "abused" scientific research to justify the creation of a seven-day NHS.
The world-renowned scientist, a lifelong Labour supporter, renewed his attack on the Health Secretary for "cherry-picking" favourable evidence while suppressing contradictory research in order to suit his argument.
The 75-year-old, who was diagnosed with motor neurone disease in 1962, said he "would not be here today if it were not for the service" and accused the Conservatives of putting the NHS in crisis.
The Health Secretary relied on research that showed higher death rates at weekends when setting out his argument for a seven-day service, although the studies were not universally accepted by the scientific community.
In tweets Mr Hunt said: "Stephen Hawking is brilliant physicist but wrong on lack of evidence 4 weekend effect. 2015 Fremantle study most comprehensive ever ... And whatever entrenched opposition, no responsible health sec could ignore it if you want NHS 2 be safest health service in world as I do."
Prof Hawking, who is director of research at the Centre for Theoretical Cosmology at the University of Cambridge, warned that Mr Hunt's actions were harmful at a time when public support for science is "more important than ever".
He wrote: "Hunt had cherry-picked research to justify his argument. For a scientist, cherry-picking evidence is unacceptable.
"When public figures abuse scientific argument, citing some studies but suppressing others to justify policies they want to implement for other reasons, it debases scientific culture.
"One consequence of this sort of behaviour is that it leads ordinary people to not trust science at a time when scientific research and progress are more important than ever."
Mr Hunt used his drive to create a seven-day NHS as one of the main reasons for reforming junior doctors' contracts - which led to the biggest walkout of doctors in NHS history.
Warning "we cannot lose" the NHS, the scientist attacked Tory policies such as the public sector pay cap, the new contract and removing the student nurse bursary.
He said the health service was being pulled in different directions by multinational corporations driven by profiting from NHS privatisation and the public, which favours a publicly funded health service.
"The NHS is in a crisis, and one that has been created by political decisions," he wrote.
"These political decisions include underfunding and cuts, privatising services, the public sector pay cap, the new contract imposed on junior doctors, and removal of the student nurses' bursary.
"Political decisions such as these cause reductions in care quality, longer waiting lists, anxiety for patients and staff, and dangerous staff shortages.
"Failures in the system of privatised social care for disabled and elderly people have placed an additional burden on the NHS."
Labour's shadow health minister Justin Madders said: "It doesn't take a genius to work out the Tories are wrecking the NHS.
"Professor Hawking has given us answers to many of the universe's most challenging questions, and even he can't work out why Jeremy Hunt is still in his job."