The ‘fat but fit’ myth has taken another hit after a new study found overweight or obese people who appear medically healthy are at increased risk of heart disease.
Researchers at Imperial College London and the University of Cambridge concluded that obese people with normal blood pressure, cholesterol and blood sugar levels were still 28pc more susceptible to heart disease than people of a healthy weight.
Published in the European Heart Journal, the study collected data from over 500,000 people in 10 European countries.
The news comes just months after a study at the University of Birmingham exposed the idea of “healthy obesity”. Analysing over 3.5 million Britons, the team found that excess fat increases the risk of heart disease by half, while also putting people at risk of stroke, Type 2 diabetes and other ailments.
What is the difference between being overweight and obese?
Obesity affects roughly a quarter of adults in Britain and one in five children aged 10 and 11. It is defined as having a body mass index (BMI) of over 30, and puts sufferers at a high risk of further diseases, most notably heart disease, stroke and diabetes.
Being overweight is less serious but still fraught with potential complications. The BMI of an overweight person is between 25 and 29.9, and there are around a billion people on Earth above the advisable weight range.
While less susceptible than obese people, being overweight can still put you at risk of the same conditions and diseases.
What is the body mass index?
BMI is a spectrum calculated on a weight-to-height ratio, to indicate where you stand in terms of the expected body weight for someone of your particular height. It is measured in kilograms per metre squared.
You can easily calculate your BMI by plugging your weight and height into an online calculator, such as the one below. However, bear in mind that this measure of BMI is often criticised by the experts for offering only a crude look into your state of health. While it can work well to establish weight trends among large groups, it is less reliable when assessing an individual, because it does not take into account whether your body mass is comprised of fat or muscle.
For example, a male athlete in peak physical condition could be 6 ft 2 and weigh 100 kg, giving them a BMI of 28, in the upper ends of the overweight bracket.
Bioeletrical Impedence Analysis
Superior on an individual level than the BMI scale is the Bio-Electrical Impedence Analysis (BIA). Bu measuring your level of fat in relation to your lean body mass, a BIA gives an indication of your body composition – ie what percentage of your weight is made up of fat. A normal body fat balance is linked to good health, while excess fat in relation to lean body mass, known as altered body composition, increases risk of heart problems and diabetes.
Unlike the BMI, a BIA test requires special equipment. Electrodes are placed on the patient’s right hand and foot and electrical currents are then sent through the body. It provides estimates of body water, from which body fat can be calculated.
Like the BMI, BIA tests have received criticism, with accuracy and efficacy called into question.
Calipers can be used to calculate body fat and fat-free mass. Skinfold calipers measure the thickness of a fold of your skin with its underlying layer of fat. Measurements are taken at key parts of the body to establish the total amount of fat in the body. Ideal caliper measurements are under 10mm.
They can be done at home providing you have the calipers, but you will need someone to help due to the location of some measurements. An equation is then used to determine body fat percentage.
DEXA (Dual Energy X-ray Absorptiometry) scans measure body composition, which is body fat and muscle mass. They also highlight visceral and subcutaneous fat and several other markers.
DEXA scans are pricier than other methods, but are often far more accurate, illustrating exactly where your fat is located. Visceral fat, for example, is stored around the heart, liver, kidney and pancreas, and can cause the likes of high blood pressure and high blood sugar which are so damaging to our health. Individuals with healthy BMIs can have dangerous levels of visceral fat, so a DEXA scan is an ideal way of finding out whether you are at risk or not.
The scans are quick and painless, involving lying on you back and being X-rayed, without the claustrophobia of an enclosed MRI scan. According to Bodyscan, DEXA scans target the three major areas of the body: arms, legs and trunk, allowing the user to target specific areas from which to lose weight.
The Bod Pod (Air Displacement Plethysmograph) is an alternative to the DEXA scan when measuring body composition.
It is a highly accurate method which uses a method called air displacement plethysmography. Clients sit in a chamber for a few minutes as the volume of air displaced by the body is used to calculate body fat percentage. It delivers similar results to the DEXA scan.