The National Health Service is to ban super-size chocolate bars from its canteens, restaurants and vending machines, NHS England said on Monday.
The move, part of a drive by UK health services to tackle obesity, will place a 250-calorie limit on sweets and chocolates sold in hospitals.
NHS officials want 80% of all items on sale to not exceed the calorie limit, meaning "grab bags" of sweets and larger chocolate barns will be removed.
Earlier this year, NHS England warned sugary drinks would likely be removed from hospitals next year.
Cans and bottles of sugary soft drinks are included in the new ban.
Simon Stevens of NHS England said: "The NHS is now stepping up action to combat the super-size snack culture which is causing an epidemic of obesity, preventable diabetes, tooth decay, heart disease and cancer.
"In place of calorie-laden, sugary snacks we want to make healthier food an easy option for hospital staff, patients and visitors."
The NHS plans to roll out more healthy foods to replace the sugary snacks. It will also curb the sale of pre-packed sandwiches that exceed 400 calories.
The rules are aimed to help NHS staff as well as patients. Some 700,000 NHS employees out of 1.3 million are thought to be overweight or obese.
"Hospitals have an important role in addressing obesity - not just treating those suffering the consequences, but helping to prevent it in the first place,” said Dr Alison Tedstone, chief nutritionist at Public Health England.
"Any plans to offer healthier food are a positive step towards tackling the country's obesity problem."