Following the lifting of restrictions by the Government, we would like to reassure all our patients that the way we interact with you will not be changing. All staff and consultants will continue to wear face coverings and maintain social distancing, and we require our patients and visitors to do the same, so that we are all protected.

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Why We're Different

  • Access to a team of specialist bariatric nurses – expert medical advice and regular medical reviews
  • Access to the hospital out of hours service
  • Access to a dietician - expert nutritional advice on making the most of the procedure you have chosen to have
  • 2 x-ray adjustments and up to 6 clinical adjustments
  • Access to your surgeon as clinically indicated
  • Access to support groups for patients
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Body Mass Index

What is Body Mass Index?

BMI is an acronym for the term body mass index. It’s a measurement of a person’s body mass index in relation to their height for all adults, irrespective of age and sex.

In 1985 the National Institutes of Health (NIH) recommended that physicians adopt the BMI as an index of obesity. It has now become the standard formula to determine what is a normal BMI weight, underweight, overweight and obese. These weight categories are used to help assess a person’s risk of obesity related diseases.

How does bmi formula work for adults?

You need to know your height and weight and input them into the standard BMI formula (height weight calculator). BMI is calculated by dividing a person’s weight in kilograms by the square of their height in metres (kg/m2) to give an average BMI for Men and/or average BMI for women.

Metric BMI formula

BMI = Weight (kg) / Height (m)²

Imperial BMI formula

BMI = [Weight (lbs) / Height (inches)²] x 703

The imperial BMI formula uses a conversion factor of 703.

How does BMI work for children?

For children the relationship between weight classification and BMI varies with age and sex. Children’s BMI measures are usually compared to a growth reference in order to determine a child’s weight status.

Some factors, for example timing of puberty or ethnicity, can make the classification of children’s BMI more complex. There are a number of different child growth references and associated thresholds. In the UK, we most often use the UK90 Growth Reference.

The link between BMI thresholds and future morbidity and mortality is weaker for children than for adults but evidence shows that children with a high BMI are more likely to have a high BMI in adulthood, and therefore a raised risk of future health problems.

How is BMI used?

BMI is a proxy measure of excess body fat. Doctors use BMI as a screening tool to signpost a person’s weight category. A person with a high BMI indicates they may have high body fatness and an overweight or obese weight status with an increased risk of obesity related illnesses. BMI is not a diagnostic tool of an individual’s body fatness or health so further tests are required.

BMI check is the most commonly used measure for monitoring the prevalence of overweight and obesity at population level.

BMI range?

BMI provides an indication of an ideal BMI. The BMI ranges are:

Underweight = BMI <18.5

Healthy BMI weight = BMI 18.5–24.9 (Average BMI)

Overweight = BMI 25–29.9

Obesity = BMI of 30 or above

Why use BMI?

BMI is an easy and non-invasive method of accurately and consistently assessing excess body fat at a population level. Excess body fat is linked to a person’s current and future morbidity. True measures of BMI are expensive or impractical and other proxy measures are more difficult to measure precisely.

BMI population data has been compiled on a worldwide scale.

Limitations of BMI

BMI has limitations. It may not be an accurate tool for assessing weight status at an individual level as it does not take into account a person’s fitness and muscle mass, their ethnic origin, body shape, age and sex. It also doesn’t provide an indication of body fat distribution.

At a population level these limitations are not seen as particularly important as they even out across large numbers of people.
Are You Eligible

Are You Eligible?

Weight loss surgery is performed to control weight. There are two basic ways that weight loss surgery works to help patients lose weight and improve both physical and lifestyle conditions.

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Benefits of Surgery

Weight loss will improve the physical and lifestyle conditions associated with being overweight.

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How Are We Different

How Are We Different?

We know how hard the fight with obesity is...members of our team have had the surgery themselves and therefore our multidisciplinary team can talk from real life experience about weight loss surgery.

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Your Aftercare

Your Aftercare

We invest heavily in resources for our post operative care. Feel safe in the hands of our specialist multi disciplinary team.

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Benefits Of Surgery

Frequently Asked Questions

Weight loss surgery is the first part of a long process, aftercare is the key to success. Support is ultimately the one part of the journey that truly does make a real difference.

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Weight Loss Prices

Weight Loss Prices

Weight loss surgery is the first part of a long process, aftercare is the key to success. Support is ultimately the one part of the journey that truly does make a real difference.

Find Out More

Weight Loss Blog

Keep up to date with the latest Ramsay Health Care weight loss blogs

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Talk to one of our dedicated weight loss enquiry handlers

Our specialist enquiry handlers will be able to help you with any questions you may have!