There is actually a diet that consists of only fruits and some nuts and seeds.
So I've heard, wasn't Steve Job on that diet?
Fruitarianism
Fruitarianism () is a subset of dietary veganism that consists entirely or primarily of fruits in the botanical sense, and possibly nuts and seeds, but without animal products. A fruitarian diet attracts criticisms and health concerns for those that follow the lifestyle.
Fruitarianism may be adopted for different reasons, including ethical, religious, environmental, cultural, economic, and health. There are several varieties of the diet. Some people with a diet consisting of 75% or more fruit consider themselves fruitarians.
Varieties.
Hunza diet
The Hunza diet consists of a series of selective food and drink intake practiced by the Hunza people of northern Pakistan that is argued by some to be unique and have long lasting effects. The diet mostly consists of raw food including nuts, fruits and seeds added with yogurt. The cooked meal, daal included with chappati, is included for dinner. It has also been advocated for being inexpensive and mostly self-producible.
Proponents.
The Irish physician Robert McCarrison is believed to have traveled to this area