As part of this research project, Hedayat observed malnourished Iranian girls weaving carpets in Kerman in poor working conditions and this caused an internal revolution in him.

He decided to focus on "nutrition" as the vital factor in the health and wellbeing of the Iranian people – a subject not taken seriously by the medical community at the time.

The institute, in collaboration with the nutrition section at the Embassy of France under the auspices of Professor Trémolières,[3] organized seminars and conferences and granted scholarships to students interested in the field.

Hedayat was invited to a UNICEF conference in New York, where Sir Herbert Broadley, the former acting director-general of FAO and UNICEF's representative in Great Britain, indicated that establishment of the Institute of Nutrition and Food Science in Iran had inspired several other Middle Eastern countries to follow suit and establish similar institutes in their respective countries.

Hedayat is author or co-author of six books, thirty-three academic papers, over fifty research reports on food and nutrition, and over one hundred presentations at national and international conferences (in Persian, English, and French).

One of his major scientific achievements was overseeing the evaluation of the nutritional status and needs of the Iranian people conducted by survey teams in 30 different urban, rural, tribal and industrial locations.

In 2005, Hedayat was elected as a member of the distinguished faculty of the College of Food Technology of Scientific Research Unit, part of Islamic Azad University.

[7] In 2006, Dr. Hedayat (together with Shahab Vaez-Zadeh) was officially recognized for his pioneering work in nutrition and food science by all sectors of the Iranian society including Ayatollah Hashemi Rafsanjani, former president and chairman the Expediency Discernment Council of Iran.