Determining whether you are a healthy weight may seem straightforward, but just getting on the scales and seeing how much you weigh isn’t the whole story.
Several factors can affect weight, such as age, gender, height, ethnicity and build. Scientists have now come up with what they think is a simpler, more accurate measure of health and the key to living longer – having a waist measurement no bigger than half your height. They also claim the rule applies regardless of age, gender or ethnicity.
Previously Body Mass Index, or BMI, was used to indicate whether you are a healthy weight for your height. BMI is calculated by dividing your weight in kilograms by your height in metres squared. However, some healthcare workers have been critical of this method, BMI doesn’t distinguish between fat and muscle. As muscle weighs more than fat, the index might determine a muscular person to be overweight or obese. Also, it doesn’t take into account the amount of fat around the waist: research has suggested that excess abdominal fat is a key indicator of future poor health.
In the study, researchers from City University London looked at two decades’ worth of data from about 300,000 adults. They came up with the simple measurement and have reported that the relationship between your height and waist circumference is an important indicator of future health. Waist circumference is important because it shows the amount of central fat in the body – which is linked to high cholesterol, diabetes and heart disease. They believe that the waist-to-height ratio is a far more reliable predictor of ill health and obesity than the BMI. It is also an easy measurement that people can do at home to monitor their health.
The study shows that ideally your waistline measurement should be no more than half your height in order to live a prolonged life. According to their developed formula, this would mean the waist of a male adult who is 5 feet 10 inches should be no larger than 35 inches. Similarly, a 5-foot-4-inch woman’s waist should measure no more than 32 inches. An increase of as many as 7 inches can trim more than one and a half years off your life expectancy. This may not sound much but as people become more obese and their waist thickens the effect on long term health increases. For example, the study suggests a 30-year-old man of 5ft 10in with a 56-inch waist can expect to lose 20.2 years from his life expectancy. Similarly a 5-foot-4-inch woman with a 51-inch waist could lose 10.6 years.
A significant amount of research has now been conducted assessing the relationship between waist size and mortality, and all the studies have led to the same conclusion that excess fat around the abdomen is more harmful than other body fat and can contribute to premature death. As long as your waist is half your height or less, the researchers predict you should live to the average life expectancy, which is currently around 81 years. But for every few inches over, you face losing months or even years of life.