The first Egyptian Arab doctor to achieve global recognition in the field of nutrition, impressing audiences with his knowledge and skills. In July 2023,  was chosen by UNESCO as the first Arab nutrition doctor to deliver a lecture at Howard University on the impact of obesity and the role of malnutrition in human capability development. This was in line with one of the objectives of the United Nations 2030 Agenda, attended by 150 students from around the world and members of UNESCO.

Dr. Ahmed Omar Salem began his journey in 2001, relying on science, talent, and an understanding of human psychology as a powerful weapon against obesity without resorting to medications or surgeries. He developed nutrition plans tailored to each individual's body. Believing that the knowledge he acquired is a gift from God and wanting to benefit humanity with it, he established his own school to combat obesity and achieve sustainable weight loss, through the DAO Academy. In 2015, he graduated doctors from his school, and the numbers have been increasing year after year.

His treatment was not limited to adults. He extended his nutritional systems to children and, in 2016, began treating childhood obesity. He also created competitions to attract obese individuals, transforming their lives for the better and incentivizing them with gold rewards for every kilogram they lost. 

In 2018, he opened his online clinic to reach clients outside of Egypt. And in 2019, he conducted courses in the Gulf countries and beyond titled "Strategies for Dealing with Excess Weight."