Nurse Guo Qinying (left) accompanies Deng Xiaoping on a walk with his grandson.[Photo provided to China Daily]

In the book, Wang recalls many stories and habits of the leader, such as Mao's preference for strong tea, his request of more coarse grains instead of rice and his favorite sport－swimming.

The simple lifestyle of Mao left a deep impression on Wang, according to the book.

Xu Fengsheng was a personal nurse to the country's first premier, Zhou Enlai, from 1964 until his death from cancer in 1976.

Xu recalls Zhou's health status was good before the "cultural revolution" (1966-76), but during that turbulent decade, Zhou became very busy, and his sleeping hours reduced drastically, which worsened his health.

Even when Zhou was diagnosed with cancer, he still kept working as much as he could, according to Xu's account in the book.

Later, Xu also served for Gu Mu, a vice-premier in the '80s. During one of Gu's foreign visits in 1985, Xu noticed something wrong with Gu's eyes and urged him to take an examination once they returned to China. Gu might have lost his vision had the problem not been detected then.

The other medical workers featured in the book include Bu Zhao-xiang, the head pharmacist of the healthcare section; Weng Yongqing, who was the personal physician to General Zhu De; and Guo Qinying, who served Deng Xiaoping.

The book's first edition was published in 2011 by People's Publishing House and reprinted for a second time earlier this year.

The interviews of the physicians were done by Ma Zhixin, the founding manager of Red Wall Bio-Engineering, a Beijing-based company that produces nutrition products, and has contact with such physicians.

"There were around 50 physicians who served the country's first-generation leaders, and only around 30 are still alive," Ma tells China Daily. "Their experiences are very precious and needed to be documented."