Television health nutritionist Gillian McKeith has agreed to drop the title Dr from her company's advertising after a complaint to the industry's watchdog.

After the Advertising Standards Agency (ASA) came to the provisional conclusion that the title was likely to mislead the public, McKeith Research said it would stop using it in advertising for future products.

The development comes less than three months after her company was censured by regulators for selling herbal sex remedies illegally.

McKeith, who has made millions with book and health food spin-offs from her programme You Are What You Eat, argues that she has a right to call herself a doctor after completing a distance learning PhD in holistic nutrition from the American Holistic College of Nutrition.

But it is understood that the basis of the complaint to the ASA was that the title was likely to mislead the public because the college had not been accredited by a recognised educational authority when she took the course.

McKeith, 47, has now agreed not to call herself a doctor on advertising for her company or its products, which include a range of health foods and cook books, removing the need for a full investigation by the ASA.

She is reported as saying that the complaint had arisen from a leaflet that did not include the disclaimer that she was not a medical doctor.

She said she understood the honorific title had to be removed from such leaflets, but not from all advertising.

"As far as I am concerned, because of the hard work I have done, I will continue to put PhD after my name and I am entitled to use the word Dr as and when I choose," she said.

Max Clifford, her PR representative, said McKeith's degree had not played a part in her career or popularity. He added: "Personally, I wish it had never been mentioned. She never needed it and it's done nothing but cause her embarrassment."

McKeith is best known for presenting the Channel 4 show You Are What You Eat in which she helps to motivate the people featured in the programme to lose weight and change their lifestyle.

The programme is currently in its fourth series in which two people are chosen to move into her London home and stick to a healthy-living regime. Last week a study revealed that the most borrowed non-fiction book in UK libraries was McKeith's You Are What You Eat.

Last November McKeith Research was warned by the Medicines and Healthcare products Regulatory Agency (MHRA) after it advertised two Fast Formula products with claims that they would deliver wonders in the bedroom for both men and women. The MHRA said the firm did not have the necessary licence to sell Wild Pink Yam complex and Horny Goat Weed complex.

It said the products were classed as medicines because of claims made about their effects and the fact that they contained medicinal herbs.