Article explaining what bariatric surgery is and highlighting the differences between the procedures

Does a high BMI make surgery riskier ?

Reading Time: 2 minutes

The truth is yes, the higher your BMI, the higher your surgical risk. In fact, it is a greater weight that increases risk, but of course greater weight usually goes hand in hand with a higher BMI (unless you are very tall).

The higher risk stems from two main factors:

  1. The heavier you are the more difficult the surgery is from a practical perspective. The amount of fat in the abdomen could be greater than normal and the liver may be bigger, for example. These factors can extend operating time which increases risk.
  2. The greater your weight the greater the risk that you have an undiagnosed weight related co-morbidity. It could be that you have undiagnosed sleep apnoea or Type 2 diabetes and these would increase the risk of a complication during surgery.

Despite there being a greater risk with a higher BMI, we have to keep a sense of perspective. Bariatric surgery is one of the safest forms of surgery today with very low mortality rates across the country. We measure mortality within 30 days as standard and no deaths have been reported within this period according to the data available.

To ensure a safe and successful surgical outcome, patients benefit from a thorough pre-operative assessment process and are reviewed by a multi-disciplinary team before their eligibility is confirmed.

When viewed alongside the risk to your health and life expectancy, the risk of surgery for the vast majority of patients is very small indeed.

We know that when patients have a BMI above 30 their life expectancy is diminished due to their weight. For those with BMIs above 40 the risk increases significantly. When battling the health issues associated with their weight, weight loss surgery offers a solution that cannot be achieved in any other way. When comparing the risk of type 2 diabetes, heart disease or cancer to the risk posed by surgery most patients opt for surgery, and rightly so. Only recently I operated on a chap who weighed more than 40 stone - his operation was widely reported on the BBC recently. His surgery went safely and according to plan. Weight loss surgery is both safe and effective and the path to better health and quality of life for most people who are eligible.

Picture of Martyn Berrett

Martyn Berrett

Martyn is the former MD of Healthier Weight. Throughout his tenure he observed many bariatric procedures and took part in several research projects so has a unique perspective on all things weight loss.

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