Detailed images of the body are taken using a CT scanner
Companies have been told to stop offering whole body and lung scans under a new regulation regime.
The Department of Health is introducing the tougher rules after a boom in so-called MOT-style scans.
Computerised Tomography (CT) scans are advertised as an MOT for people who want to be checked for illnesses.
But experts say there are risks to having unnecessary scans. They can be up to 400 times more powerful than a chest X-ray.
The government made the announcement after accepting the recommendations of its expert advisers, the Committee on Medical Aspects of Radiation in the Environment (COMARE).
Scanning for spinal conditions, osteoporosis and body fat will also cease.
COMARE also recommended that screening for colorectal cancer - outside of the NHS screening programmes - should only be undertaken in over-50s.
In keeping with the NHS screening programmes, scans should not be performed more frequently than once every two or three years.
The committee made nine recommendations in total and the Department of Health has accepted all of then.
CT scanners use X-rays to take detailed images of cross sections of the body called "slices". The scanners can have different numbers of detectors.
Generally the greater the number of detectors, the increased amount of data that is acquired leading to more detailed images of the body.
The images are stored in a computer and are interpreted by a radiologist.
The Department of Health will now seek the help of the Royal College of Radiologists and the Royal College of Physicians in preparing guidance for practitioners.
The guidance will focus on the balance of risk and benefit involved in the CT scanning procedures.
Dr Tony Nicholson, dean of the Royal College of Radiologists, said: "This regulation will make the rules on CT scans more understandable. It's just not possible to justify using ionising radiation if there's no proven benefit."
Public Health Minister Gillian Merron said: "Any scan a patient undergoes should balance the clinical benefits against the risks of the radiation involved.
"I welcome the decision to define more closely the considerations that should govern CT scanning in cases of individual health assessments," she added.