A clampdown on clinics offering MOT health checks to the worried well – which can include whole body scans – was signalled by the government today, amid concerns over the exposure of healthy people to unnecessary radiation.

The Department of Health said it accepted all nine recommendations of the government's advisory committee on medical aspects of radiation in the environment (Comare), which called for action more than two years ago.

Comare warned that CT (X-ray computed tomography) scans could increase a person's cancer risk. It wanted whole body scans, which are carried out on a speculative basis to see if anything might be wrong, to be banned, on the basis that the risk from exposure to radiation exceeded the benefit.

It said CT-scanning machines were contributing significantly to the radiation exposure of the population. Some 15% of our exposure in the UK comes from medical sources – almost half of that from CT scans.

Calling for greater regulation of CT scans, Comare recommended an end to their use for spinal conditions, osteoporosis and assessing body fat. There was a limited case, however, for the continuation of CT scanning for heart disease among those of intermediate risk and for colon cancer, though only in the over-50s unless referred by a specialist.

But while the government says it fully backs Comare's conclusions, its response stops short of any kind of ban.

Instead, the Department of Health says it will ask the Royal College of Radiologists and the Royal College of Physicians to prepare guidance for doctors "based on the balance of risk and benefit involved in the CT-scanning procedures concerned".

It says that commercial CT scans will be reclassified as "individual health assessments" to make it clear they are not diagnostic scans, and they will be brought under greater regulation within the private clinics.

CT scans can be 400 times more powerful than chest X-rays, it points out. Because they are carried out in private clinics on a commercial basis, the patient does not see their GP who would be able to weigh the likely benefit to the individual against the risk.

The health minister, Gillian Merron, said: "I am grateful to Comare for its work in this important area.

"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."

"I look forward to working with the royal colleges of radiologists and physicians to develop practitioner guidance."

Private screenings can cost many hundreds of pounds. Sometimes they appear to show problems which are in fact only benign, harmless abnormalities. This causes anxiety to the patient and may even lead to unnecessary investigations – often paid for by the NHS.

An average CT scan is said to be associated with a one in 2,000 lifetime risk of developing a cancer, which is low compared with the average normal lifetime risk of one in four.

But, said the Comare report, the risk should not be dismissed. "If 100,000 people undergo a CT scan every five years from age 40 to 70 years … then the estimated impact is approximately 240 excess fatalities," it said.