New research suggests a BMI of 27 is obese, but that’s still not accurate enough, says expert

New research suggests a BMI of 27 is obese, but that’s still not accurate enough, says expert.

Controversial new research measuring body fat levels has concluded a lower BMI of 27 rather than 30 to determine obesity is more accurate. The finding has captured headlines around the world. However, a leading expert says a quick and simple blood test to measure heart health is more valuable.

A controversial new Italian study has found that measuring body fat levels rather than our body mass index (BMI) gives a truer picture of who is obese.

Currently, a BMI of up to 25 for an adult is considered healthy, while up to 29 is overweight and 30 or above is considered obese. However, the researchers found this does not take into account the fact that muscle declines and fat builds up as we get older, leading to considerably more body fat with no gain in weight.

To allow for this shift, the study, published originally in the journal Nutrients but recently presented at the European Congress on Obesity, found that a BMI of 27 should be used to define obesity in future.

The study, led by researchers at the University of Tor Vergata in Rome, set out to challenge the traditional BMI measure of 30 to determine obesity, which is currently accepted in most countries and supported by the World Health Organisation (WHO).

The researchers say: ‘Due to changes in body composition that occur across the lifespan, with an increase in BF (body fat) and a decrease in lean mass, we aimed to test the validity of this BMI cutoff point… In a real-world clinical setting, a new BMI cutoff point (BMI = 27.27 kg/m2 ) has been identified for predicting obesity in middle-aged and older adults.’ The researchers conclude obesity guidelines should be revised accordingly.

However, a leading expert says that simply using a broad body fat measure, even one more accurate than the traditional BMI reading, still does not give a true picture of the stress on people’s hearts or their overall health in relation to their weight.

Dr Avinash Hari Narayanan (MBChB), Clinical Lead at London Medical Laboratory, says: ‘It’s certainly high time that a more meaningful instant snapshot of how our weight might be impacting our health was introduced. The traditional BMI measure of dividing an adult's weight in kilograms by the square of their height in metres is quick and easy, and reducing the obesity measure to 27 may give a better picture of our overall likely weight and health balance, but the fact is that technology has moved on.

‘Today, a simple and quick finger-prick blood test can swiftly analyse some of the most important risks to our heart health. One rapid test will measure the risk of high cholesterol, diabetes and generalised inflammation, which all dramatically increase the potential of future heart attacks.

‘A heart health finger-prick blood test includes a full cholesterol profile, measures HbA1c to determine if someone has diabetes or is pre-diabetic and shows our CRP (C-reactive protein) level. This high sensitivity CRP level measure indicates the presence of inflammation.

‘Inflammation is bad for your heart. A high CRP level can also indicate the presence of a very wide range of other health problems like autoimmune disease, bacterial infections, osteomyelitis, pelvic inflammatory disease and inflammatory bowel disease.

‘Obviously, there is still a need for a BMI test as a general indicator that our weight may be impacting our health. However, with the arrival of new blood testing technology, BMI ought to be taken as a reading in conjunction with a heart health test. While we can begin to gauge overall body fat level simply by looking at someone, their risk from “silent killers” such as diabetes, high cholesterol and inflammation is not so easily identified.

‘Finger-prick heart health tests can be done in GP surgeries, as phlebotomy tests in clinics and pharmacies or, importantly, as a simple home test available through the post. That means determining your heart health is no harder than measuring your BMI.

‘For example, London Medical Laboratory’s simple, finger-prick blood test indicates risks to heart health and includes a full cholesterol profile, as well as testing for inflammation. It also tests for diabetes, showing how well the body is controlling blood sugar.

‘The Heart Health Profile test can be taken at home through the post, or at one of the many drop-in clinics that offer these tests across London and nationwide in over 120 selected pharmacies and health stores. For full details see: https://www.londonmedicallaboratory.com/product/heart-health-profile