Weight loss surgery (Bariatric surgery) | Dr Samson Olori

What is bariatric surgery?

Bariatric (weight loss) surgery changes the stomach and sometimes the intestines to limit how much you can eat and, in some procedures, how much you absorb. It is considered when obesity is affecting your health and other treatments have not worked. Common types include gastric bypass (smaller stomach pouch plus rerouted intestine), gastric sleeve (most of the stomach removed, leaving a sleeve), adjustable gastric banding (band around the stomach that can be tightened or loosened), and biliopancreatic diversion with duodenal switch (more extensive restriction and malabsorption). The best option depends on your weight, health conditions, and goals—we can refer you to a specialist team for assessment.

Who is it for and what are the benefits?

Surgery is usually offered to adults with a body mass index (BMI) of 40 or more, or BMI 35–40 with obesity-related conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. Benefits include substantial and often sustained weight loss, improvement or remission of type 2 diabetes in many patients, better blood pressure and cholesterol, reduced sleep apnoea, and improved quality of life. It is a major operation and requires a lifelong commitment to diet, vitamins, and follow-up.

Risks and complications

As with any major surgery, there are risks: infection, bleeding, reaction to anaesthesia, blood clots, and leaks from the stomach or intestine. Longer-term complications can include gallstones (especially with rapid weight loss), nutritional deficiencies (vitamins and minerals), dumping syndrome (nausea, dizziness after eating sugary or fatty foods), narrowing at the connection between stomach and intestine (stomal stenosis), and ulcers. Regular follow-up with your surgical and dietetic team helps prevent and manage these. Pre-operative assessment and education are essential to prepare you and reduce risks.

Recovery and diet after surgery

You will start with liquids, then purees and soft foods, then gradually solid foods in small portions. Eating too quickly or too much can cause discomfort or vomiting. We advise lean protein, vegetables, fruits, whole grains, plenty of water (not with meals), and avoiding high-calorie, sugary, and carbonated drinks. Small, frequent meals and lifelong vitamin and mineral supplementation are standard. Physical activity is encouraged as you recover. Follow-up appointments are needed to monitor weight, nutrition, and any complications.

Frequently asked questions

Is bariatric surgery safe?
It is a major operation with real risks, but in suitable patients with good preparation and follow-up, it is generally safe and very effective for weight loss and improving obesity-related diseases.
How much weight will I lose?
Weight loss varies by procedure and individual. Many people lose a significant amount of excess weight in the first 1–2 years. Long-term success depends on diet, activity, and follow-up.
Will I need to take vitamins forever?
Yes. After bypass or malabsorptive procedures, lifelong supplementation with vitamins (e.g. B12, folate) and minerals (e.g. iron, calcium) is usually required to prevent deficiency.