Yoshinori Ohsumi of Japan received the 2016 Nobel prize for medicine for discovering mechanisms behind how human body cells recycle their components, the prize jury announced on Monday.
The science behind the process of recycling of cell components, called authophagy or self-eating, has led to a better understanding of diseases such as cancer, Parkinson's and type 2 diabetes.
Ohsumi's discoveries "have led to a new paradigm in the understanding of how the cell recycles its contents," the jury said.
"Mutations in autophagy genes can cause disease, and the autophagic process is involved in several conditions including cancer and neurological disease," the jury added.
Researchers first observed during the 1960s that the cell could destroy its own contents by wrapping them up in membranes and transporting them to a recycling compartment called the lysosome, a discovery that earned Belgian scientist Christian de Duve a Nobel Medicine Prize in 1974.
It was de Duve who coined the term "autophagy", which comes from the Greek meaning self-eating.
In what the jury described as a "series of brilliant experiments in the early 1990s", Ohsumi used baker's yeast to identify genes essential for autophagy.
He then went on to explain the underlying mechanisms for autophagy in yeast and showed that similar sophisticated machinery is used in human cells.
Ohsumi's findings opened the path to understanding the importance of autophagy in many physiological processes, such as how the body adapts to starvation or responds to infection.
Ohsumi, born in 1945 in Fukuoka, Japan, has been a professor at the Tokyo Institute of Technology since 2009. He told Kyodo News agency he was "extremely honoured" to get the prize.
In a separate interview with broadcaster NHK, he said he had "always wanted to do something that other people wouldn't do".
"I thought the breakdown (of cells) would be interesting, and that was my start," he said.
The Nobel medicine prize is worth 8 million Swedish crowns ($933,000).
The 2016 Nobel season is to continue on Tuesday with the physics prize announcement, followed by the chemistry prize on Wednesday.
On Friday, all eyes will turn to Oslo where perhaps the most prestigious of the prizes, the peace prize, will be announced.