Waist to Height Ratio

Waist-to-height ratio (W/Ht) is increasingly being used in preference to Body Mass Index (BMI) as a better measurement of the risk of obesity and cardiovascular disease. A recent British study based on 20 years of medical records is the first study to quantify how many years you will lose to an earlier death. This ratio applies to both adults and children, and regardless of a person’s age, ethnicity or gender. The advice is to keep your waist circumference less than half of your height.

The problem with BMI is that is does not always accurately indicate the degree of fatness of a person. It is increasingly agreed that the degree of central fat distribution may be more closely tied to metabolic risks than BMI. Consequently the measurement of the degree of central fat distribution thus appears to be important for the early detection of subsequent health risks and number of years of life lost, even among those of normal weight. By measuring the waist-to-height ratio you are getting an earlier predictor that an obesity-related health condition is developing and that you can do something about it and reverse or prevent the onset of obesity related illnesses and cardiovascular disease if this is checked early enough. This simple measurement provides a life expectancy of obesity, as measured by the ratio between waist and height.

Another measurement that has gained preference with doctors as a predictor of obesity is the waist-to-hip ratio (WHR), which has been used as an indicator or measure of the health of a person, the risk of them developing serious obesity-related health conditions and reduced life span. Research shows that people with “apple-shaped” bodies (with more weight around the waist) face more health risks than those with “pear-shaped” bodies who carry more weight around the hips. The measurement of the hips at the widest point is often inaccurately measured and therefore the waist-to-height ratio is less prone to erroneous measurement.

How to take the measurement
The beauty of this measurement is that you can do it in centimetres or inches, it doesn’t matter. Find your waist, which is halfway between the lowest rib and the hip bone or the narrowest point of your body and just above your belly button and don’t breathe in.

The calculation is:

Waist x 100
                         = %
Height

Healthy Weight 50%
Generally if you have a ratio of 50% you have an ideal waist-to-height ratio and have a low risk of weight-related disease but it is important to maintain your shape with a healthy diet and regular activity. The longer you can prevent central fat deposition, the longer and healthier your life will be.

Overweight 60%
You are already overweight and have some central fat deposits if your ratio is between 60-70%. This fat is stored as body fat and also visceral fat that deposits around your internal organs and in the membranes called the ‘omentum’ that line the abdominal cavity. This fat will have started to produce the hormone and chemicals which increase your risk of obesity-related and cardiovascular diseases. Disease progression can be prevented by reducing the waist-to-height ratio and your lifespan will be reduced by a modest amount but this is preventable.

Obese 70%
A high ratio of over 70-80% is associated with obesity is indicative of centrally stored body and visceral fat and an increased risk of disease. You may not have symptoms yet of disease such as blood vessel inflammation and hardening which lead to stroke, high blood pressure, heart disease, hormonal changes causing infertility, pre-cancerous tissue change, and diabetes. It is important to stop the damage before it worsens – by the time you have symptoms, the damage is already severe. Life expectancy within this ratio grouping is severely impacted, with a heightened difference between males and females.

Morbidly Obese 80%+
With a large abdominal girth you are extremely likely to be holding dangerous amounts of fat centrally, and be at high risk of disease associated with this. You may already have symptoms of disease such as blood vessel inflammation and hardening which lead to stroke, high blood pressure, heart disease, hormonal changes causing infertility, pre-cancerous tissue change, and diabetes. You are also at risk of fat deposits in the liver (fatty liver) that could lead to cirrhosis of the liver. Your lifespan will be severely shorten, with progressively poorer quality of life in that later years of life due to long-term disease and multiple comorbidities (more than one long-term health condition).