Edinburgh doctor Gregor Venters raised his concerns about the privatization of the UK's health services at the annual British Medical Association (BMA) meeting in Liverpool.
"One of the other issues that has been discussed in TTIP is the introduction of private providers into public services.
"This will allow the big American corporations to interfere with the NHS."
"Private corporations could use the process to bully governments into dropping legislation to improve food standards."
Also speaking at the meeting in Liverpool, Belfast GP Dr Henry McKee warned members that "if there is anything resembling an NHS by the time this treaty is negotiation, it won't survive this treaty."
"The correct motion is to kill this treaty dead, not to tolerate it sneaking in and mugging us."
The BMA has lobbied extensively in the UK and in Europe on the potential impact of TTIP on the NHS.
Members are mainly concerned with the prospect of investor-to-state dispute settlements and the protection investors would have, allowing corporations to sue governments should a change in policy or legislation cause commercial loss.
Excluding Doctors from TTIP Negotiations — 'Alarming'
According to a United Nations Independent expert, the exclusion of health professionals is alarming.
An independent UN expert on the promotion of a democratic and equitable international order, in an interview published on the United Nations website, said that the exclusion of labor unions, consumer unions, health professionals and environmental experts as key partners in TTIP negotiations is alarming.
"We have seen retrogression in human rights and this is something that has to be addressed now," said Alfred de Zayas,
The independent expert will present a detailed report on the issue of free trade and investment agreements and the impact on human rights, to the UN Human Rights Council and the UN General Assembly later in the year.