Your Bariatric Surgery Questions Answered
Get answers to common queries about bariatric surgery, procedures, recovery, and more to help you make informed decisions about your health.
Frequently Asked Questions
What is obesity?
Obesity is a chronic disease characterized by excessive body fat that negatively impacts health. It is typically defined as a BMI ≥ 30 kg/m² and is linked with conditions like diabetes, hypertension, and heart disease.
How is BMI classified?
- Overweight: BMI 25–29.9
- Obesity Class I: 30–34.9
- Class II: 35–39.9
Class III (morbid obesity): ≥ 40
What causes obesity?
Multiple factors contribute, including genetics, hormonal imbalances, environment, behavior, and medical conditions. It’s not simply a matter of willpower.
Who is eligible for bariatric surgery?
Candidates typically have:
- BMI ≥ 40, or
- BMI 35–39.9 with significant comorbidities (e.g., diabetes, hypertension, sleep apnoea)
- Some centres accept BMI 30–34 with type 2 diabetes or other chronic medical conditions.
Are there age limits for surgery?
Generally 18-65 years, though some centres consider older adults case-by-case
What tests are needed before surgery?
Standard pre-op investigations include blood tests, ECG, urinalysis, psychological assessment, sleep study, pulmonary evaluation, radiological investigations and GI tests such as gastroscopy.
How long is the surgery and hospital stay?
Most procedures take around 3-4 hours. Hospital stays averages 2-3 nights in a general ward.
How much weight will I lose?
Typically 60-70% of excess weight:
- Gastric bypass: ~70%
- Sleeve gastrectomy: ~60%
Weight loss is faster with bypass in initial months, then slows over a year.
Will I regain weight?
Some regain (about 5% of lost weight) is common after 2 years. Long-term success relies on lifestyle adherence and follow-up.
How does surgery help with weight loss?
It reduces stomach size and/or nutrient absorption and changes gut hormone signals (e.g. ghrelin, leptin) to reduce appetite and reset satiety.
Can I stop medications after surgery?
Many patients can reduce or discontinue medications for diabetes, hypertension, and sleep apnoea due to dramatic health improvements.
Do I need lifelong vitamin supplements?
Yes. Multivitamins and extra iron, calcium, vitamin D, and B12 are typically required after malabsorptive surgery, with periodic blood tests recommended.
When can I exercise?
Patients can begin with gentle walking. After a month, low-impact exercise is encouraged, with individualised fitness plans based on ability.
What diet changes are needed?
Stages include:
- Clear liquid
- Pureed/soft foods
- Regular healthy diet with smaller portions, slow eating.
Is hair loss normal?
Temporary hair thinning at 3-6 months post-op is common. Proper protein and nutrient intake helps recovery.
What are potential complications?
Risks include dumping syndrome, gallstones, kidney stones, ulcers, strictures, nutrient deficiencies, and GORD, all relatively uncommon and manageable.
Can I get pregnant after surgery?
Women are advised to delay pregnancy for 12-18 months post-surgery. Pregnancy outcomes are typically healthier, with lower complication rates.
Will I need cosmetic surgery?
Significant weight loss often leads to excess skin. Some may choose body contouring procedures after stabilising weight for at least 6 months. Our Plastic Surgeon, Prof C Sofianos and his team, will be able to guide you.
Suggestions for Next Steps
- Attend informational seminars or “Bariatrics 101” sessions to learn about options.
- Schedule a consultation with a multidisciplinary obesity care team.
- Begin your pre-op program, including diet changes, exercise, and medical optimisation.
- Arrange support group participation for ongoing motivation and community.