Introduction to Gastric Bypass Surgery
Gastric bypass surgery is often considered the gold standard in weight loss surgery. It’s been the procedure by which all newer weight loss surgeries are compared. There are different variations of the gastric bypass, but they all share a common structure. The procedure creates a small rectangular gastric pouch, roughly 20-30ml in volume, made from the upper stomach. The small intestine is then connected to this pouch, and ingested food bypasses the stomach and the duodenum, starting digestion further down the small intestine.
In practice, there are two primary types of gastric bypass:
Roux-en-Y gastric bypass, first performed in 1967, and
One anastomosis gastric bypass (also known as mini gastric bypass or loop gastric bypass).
Additionally, the procedure can be tailored to individual patients by adjusting the length of the bypassed intestine or placing a ring around the pouch to prevent stretching. While this customization may lead to better weight loss or better management of metabolic conditions like diabetes, it also introduces potential risks like malnutrition and diarrhoea.
Both types of gastric bypass are generally performed via laparoscopic (keyhole) surgery, requiring only one or two nights in the hospital.
How Does Gastric Bypass Surgery Work?
Gastric bypass surgery has both physical and hormonal effects on the body. Physically, the small gastric pouch restricts food intake, leading to reduced portion sizes and an early feeling of fullness. Overeating will cause discomfort and vomiting. While the primary reduction in calorie intake results from this restriction, some malabsorption of fat, minerals, and vitamins may occur, particularly with one anastomosis and long-limb gastric bypasses. To prevent nutritional deficiencies, patients must take daily vitamins and minerals, have regular dietetic reviews, and undergo routine blood tests.
Hormonally, the gastric bypass reduces appetite. Although the exact mechanism isn’t fully understood, many patients report feeling much less hungry after surgery, sometimes forgetting to eat. The surgery also influences hormones related to blood sugar regulation, leading to remission of Type 2 diabetes for many patients, eliminating the need for diabetes medications.
Weight Loss and Medical Benefits of Gastric Bypass Surgery
On average, patients undergoing gastric bypass will lose 65-70% of their excess weight. For example, a person who is 5’6″ (1.67m) tall and weighs 20 stone (130kg) with a BMI of 45 will typically lose over six and a half stone (42kg), resulting in a long-term weight of around 14 stone (88kg). This compares favourably with other procedures, such as the gastric band (49% weight loss) and sleeve gastrectomy (60% weight loss).
In addition to significant weight loss, gastric bypass surgery has profound effects on obesity-related conditions:
70-80% of Type 2 diabetes patients will go into remission and no longer need medication.
70% of patients with high cholesterol can stop their medication.
70% of patients with high blood pressure will be cured, or their medication will be significantly reduced.
86% of patients with obstructive sleep apnoea experience complete resolution.
Many patients with arthritis experience improved mobility.
Acid reflux is often cured (with Roux-en-Y gastric bypass only).
Gastric Bypass Surgery Variations
1. Roux-en-Y Gastric Bypass (Laparoscopic)
Laparoscopic Roux-en-Y gastric bypass (LRYGB) has been the gold standard for many years. It’s a reliable, long-term solution for weight loss, first performed in the USA in 1967. Though it was once the most commonly performed procedure globally, it has recently been surpassed by sleeve gastrectomy. LRYGB now involves laparoscopic (keyhole) surgery, resulting in a shorter hospital stay (1-3 nights) and quicker recovery.
Side Effects:
Dumping syndrome
Rapid alcohol absorption
2. One Anastomosis Gastric Bypass
The one anastomosis gastric bypass (also known as mini gastric bypass or loop gastric bypass) is a newer variant of the Roux-en-Y procedure. It only requires one join, rather than two. The gastric pouch is longer and narrower, similar to a sleeve gastrectomy, and between 100-250 cm of the small intestine is bypassed. This procedure can lead to better weight loss and improved diabetes resolution but also increases the risk of side effects like diarrhea and nutritional deficiencies.
Side Effects:
Gastro-oesophageal reflux disease (acid and bile reflux)
Offensive-smelling bowel movements
Increased risk of vitamin and mineral deficiencies
Dumping syndrome
Rapid alcohol absorption
Dumping Syndrome
Dumping syndrome is a common side effect following gastric bypass surgery, especially if high-fat or sugary foods (like chocolate, cakes, and ice cream) are consumed. Symptoms include nausea, sweating, anxiety, abdominal cramps, diarrhea, and extreme drowsiness. While unpleasant, dumping syndrome can serve as a useful deterrent to eating unhealthy foods.
Why Does Holding Excess Weight Reduce Our Ability to Be Active?
A fundamental aspect of losing weight is that your body becomes more efficient at moving. Initially, excess weight makes everyday activities more challenging. For example, walking up a steep hill might leave you out of breath due to the extra weight you’re carrying. However, as you lose weight, you’ll find that movement and exercise become progressively easier. Your body will no longer have to exert as much force to move, leading to improved stamina and activity levels over time.
You can read more about this in our blog: Exercise After Weight Loss Surgery: Why It Matters for Long-Term Success
Eating and Drinking After Gastric Bypass Surgery
In the early days and weeks after gastric bypass surgery, eating and drinking can be challenging. It may be difficult to drink enough fluid, and eating can be slow and uncomfortable due to post-operative swelling. However, as the body heals and adjusts, patients can resume a more varied diet. It’s essential to follow a structured eating plan, including stages like pureed foods, soft foods, and eventually solid foods.
Key tips for eating after surgery include:
Eating slowly and chewing food thoroughly
Taking small portions and waiting between bites
Avoiding overconsumption of high-fat and sugary foods
It’s vital to maintain a balanced diet to ensure adequate nutrient intake, particularly protein, while avoiding malnutrition. Regular consultations with a dietitian are essential to support long-term success.
What Is the Cost of Gastric Bypass Surgery?
A common question that comes up is: How much does gastric bypass surgery cost? The price of the procedure can vary depending on the provider, the complexity of your case, and which aftercare package you choose.
At Streamline Weight Loss, our prices for gastric bypass surgery start from £9,950. This includes a fully supportive, 1:1 aftercare programme:
Your initial consultation and pre-operative assessments
Surgeon, anaesthetist, and hospital fees
Post-operative care and follow-up support
Access to an expert dietitian for 1:1 support
Instant access to our customer care team via WhatsApp
We pride ourselves on offering transparent pricing with no hidden costs, so you know exactly what to expect from the start.
While the upfront cost may seem significant, it’s important to consider the long-term benefits. For many patients, gastric bypass surgery is a life-changing investment in their health, potentially reducing or even eliminating the need for expensive medications and long-term treatments for conditions such as Type 2 diabetes, high blood pressure, and sleep apnoea.
The tailored and comprehensive aftercare packages we offer at Streamline are included in some of the prices you may have seen advertised from providers abroad, and you can read more about that here: Weight loss surgery in Turkey – is it safe?
