NHS practitioners place great importance on maintaining a ‘healthy’ Body Mass Index (BMI), calculated by determining an individual’s height to weight ratio; but is there too much emphasis placed on achieving an ideal weight over following a healthy lifestyle?

<18.5 Underweight
18.5 – 24.9 Healthy Weight Range
25 – 29.9 Overweight
30 – 39.9 Obese

https://www.nhs.uk/common-health-questions/lifestyle/what-is-the-body-mass-index-bmi/

BMI ranges are thought to be useful tool in determining risk of developing conditions such as diabetes, high blood pressure, cholesterol and some cancers; but they may be misleading as a general indication of good health. BMI calculations cannot determine fat from fat free mass, nor can they establish if an individual is consuming a healthy well balanced diet.  It is therefore possible that a person consuming a diet of nothing but processed foods could be considered a ‘healthy’ weight, whilst an athlete eating a nutrient rich diet, who achieves additional muscle mass through frequent exercise could be labelled as overweight or obese.

This has been supported in recent studies examining global blood pressure, cholesterol and blood sugars. It was found that nearly half of all people considered ‘overweight’ by BMI actually had healthy cardiometabolic profiles, whilst a third of those with ‘normal’ BMI were found to have an unhealthy profile.

The media is saturated with negative language and images that stigmatise those in larger bodies and spreads the preconception that those who exceed a BMI of 25 must be unhealthy. This is potentially unfounded and not only creates unnecessary prejudice but can have a detrimental effect on a person’s mental and physical wellbeing. BMI concerns are also linked to increased risk of disordered eating, whereby individuals adopt unhealthy eating behaviours in order to achieve a body weight and shape deemed acceptable in wider society.

The weight loss industry is thought to be worth almost 260 million dollars yet dieting is rarely successful long term and can often lead to feelings of sadness and failure if goals are not met. Rather than focus on weight loss to achieve an ‘ideal’ BMI, perhaps more importance should be placed on encouraging everyone to engage in healthier lifestyle behaviours. Studies have shown that just by eating 5 fruit ang veg a day, not smoking, drinking alcohol in moderation and engaging in regular exercise, individuals can reduce their risk of all-cause mortality irrespective of BMI.

If a person’s size is compromising their immediate health then it may be wise to encourage healthier eating and an increase in activity but current BMI ranges are potentially too limited and unhelpful in motivating weight loss.  As a society we need to encourage more body acceptance, exercising for fun and eating well to feel great.