Bariatric surgery is one of the most effective long-term treatments for severe obesity, but success isn’t just about losing weight. It’s about improving your health, enhancing your quality of life, and achieving sustainable results. So, how do we measure success after bariatric surgery? Let’s break it down.
What Does Success Look Like After Bariatric Surgery?
- Significant and Sustained Weight Loss: Losing a meaningful amount of weight and keeping it off long-term.
- Improvement or Resolution of Obesity-Related Conditions: Conditions like diabetes, high blood pressure, and sleep apnoea often improve or even disappear after surgery.
- Enhanced Quality of Life: Many patients report better mobility, increased energy, and improved mental well-being.
While weight loss is a major goal, it’s important to remember that success isn’t just about the number on the scale. Even a modest weight loss of 5-10% of your total body weight can lead to significant health benefits.
How Do We Measure Weight Loss After Surgery?
Weight loss after bariatric surgery is typically measured using two methods: Excess Weight Loss (%EWL) and Total Weight Loss (%TWL). Here’s what they mean:
1. Excess Weight Loss (%EWL)
%EWL measures how much of your extra weight you’ve lost compared to a healthy weight.
Calculation:
- Excess Weight = Initial Weight - Ideal Weight
- %EWL = [(Initial Weight - Postoperative Weight) / (Initial Weight - Ideal Weight)] × 100
For example, if your initial weight was 140 kg and your ideal weight is 70 kg, your excess weight is 70 kg. If you lose 35 kg, your %EWL is 50%.
2. Total Weight Loss (%TWL)
%TWL measures how much of your total body weight you’ve lost.
Calculation:
- %TWL = [(Initial Weight - Postoperative Weight) / Initial Weight] × 100
For example, if your initial weight was 140 kg and you lose 28 kg, your %TWL is 20%.
A %TWL of 20% or more is considered a successful outcome.
How Much Weight Can You Expect to Lose?
Sleeve Gastrectomy
- Average %EWL at 3 years: ~60%.
- Most weight loss occurs in the first 6 months, stabilising between 9-12 months.
- A small weight regain of 1-5 kg after the first year is normal due to metabolic adaptation.
Gastric Bypass (RYGB & OAGB)
- RYGB %EWL: 65-75% at 3 years.
- OAGB %EWL: 70-80% at 3 years.
- Average %TWL at 3 years:
- RYGB: 25-35%
- OAGB: 30-40%
Weight Loss After Revision Surgery
Patients undergoing revision surgery (e.g., converting a sleeve to a bypass) typically lose less weight than those undergoing a primary operation.
- Lower expected %EWL and %TWL compared to primary surgery.
- Previous weight loss, metabolic adaptation, and surgical complexity influence outcomes.
Managing Your Expectations
Setting realistic goals is key. Studies show that:
- Two-thirds of patients expect to lose more than 50% of their excess weight.
- Some feel disappointed even with clinically successful weight loss.
Success Is More Than Just Weight Loss
Bariatric surgery offers many benefits, including:
- Improved Health: Many patients see their diabetes, high blood pressure, and sleep apnoea improve or resolve.
- Better Quality of Life: Increased mobility, self-esteem, and mental well-being.
- Long-Term Sustainability: With the right lifestyle changes, the results of bariatric surgery can last a lifetime.
Ask Yourself These Questions
- What is the minimum weight loss I would be happy with?
- Am I prepared for the lifestyle changes required, including dietary adjustments and physical activity?
- Do I understand that results vary and that success is about more than just the number on the scale?
Final Thoughts
Bariatric surgery is a powerful tool, but it’s not a quick fix. Long-term success depends on your commitment to lifestyle changes, including a healthy diet, regular exercise, and follow-up care. If you’re considering surgery, talk to your healthcare provider about your goals and how to prepare for the journey ahead.
Take the Next Step
If you're considering bariatric surgery, book a consultation with our expert team today. We're here to help you start your journey towards a healthier, happier life.
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