Burgas University Hospital (UMBAL Burgas) is offering free checks of metabolic age and body composition on 16, 17 and 18 November, from 11am to 1pm. The hospital said people who are overweight and have not been diagnosed with diabetes can come.

No referral from a GP and no booking are needed. Those who want a check should go straight to the endocrinology department on the sixth floor of the Therapy Building, the hospital's tall tower.

The checks mark World Diabetes Day on 14 November. They aim to prevent diabetes and catch it early. The campaign continues the hospital's work on early detection of metabolic disorders.

The test uses a professional body composition analyser. It measures the share of fat, muscle and water in the body, the basal metabolic rate and what is known as metabolic age. Metabolic age is worked out by comparing a person's calculated metabolic rate with the typical rate for different age groups. It can sometimes differ a lot from a person's real age.

The test is quick, painless and non-invasive. It gives far more data than simply weighing yourself or calculating body mass index. People stand on the device barefoot, so the hospital advises wearing socks, not tights.

A doctor will explain the results to each person. The doctor will also give advice on diet, exercise and weight control, and say whether more tests are needed.

According to the hospital, built-up fat, especially around the internal organs, raises the risk of insulin resistance, type 2 diabetes and heart and blood vessel disease. It adds that a poor ratio of fat to muscle is possible even when weight looks normal.

In the hospital's earlier campaign, "Don't wait for diabetes, get tested today", 150 people signed up. Among those tested, doctors often found obesity and risk factors for diabetes.