The new mandate, which the county will implement starting July 1, requires items served in county facilities to be more nutritious with specific guidelines for reducing fat, sugar and salt.
Hospitals and jails will see the biggest changes. Some foods that are fried or simply contain too much sugar will be eliminated altogether.
"We know that the obesity epidemic is just as severe here in Santa Clara County as it is everywhere. It certainly harms individuals' health but it also is costing the county millions and millions of dollars," said Santa Clara County Supervisor Ken Yeager.
There will also be big changes in what can be bought at county-owned or leased vending machines. No more soda or junk food will be available.
The county already requires half of the beverages and snacks stocked in its 200 vending machines to be healthy options, and some say the new policy goes too far.
"I think though it's a personal responsibility to make your meal more nutritious, not the county's, so I think people need to take responsibility for their own diet," said Johnee Stebbins, a county employee.
The people behind the anti-obesity campaign say the county is not trying to dictate what people eat but lead by example.
"We've been doing this but this is a major effort in really walking the talk and doing something and hopefully others in the country will take our example and utilize it," Santa Clara County Health Officer Marty Fenstersheib said.
Santa Clara County was also on the cutting edge when it first tackled fast food kids' meals and menu labeling for restaurant chains.