Despite the common goal of long-term weight loss between gastric bypass vs lap band, both types of bariatric surgery procedures are significantly different. The most notable difference between the surgical weight loss options is that gastric bypass is a more invasive surgery that reroutes your digestive tract to reduce food intake and absorption of calories (nutrients).

In contrast, lap band surgery is a purely restrictive procedure that doesn’t surgically alter your digestive tract. Instead, the lap band procedure promotes weight loss by wrapping an inflatable gastric band around the top part of your stomach, which creates a small pouch (1-2 oz).

Difference Between Gastric Bypass vs Lap Band

Although both procedures are highly effective at achieving weight loss, gastric bypass remains the most commonly performed type of bariatric surgery worldwide. About 160,000 gastric bypass surgeries are performed each year in the United States, alone.

The following chart provides a side-by-side comparison between the two procedures.

 RNY Gastric Bypass Gastric Lap Band
Surgical RiskModerateLow
Rate of
Weight Loss		RapidSlow and steady
Average
Weight Loss		60-85% of excess body weight within 12-18 months40% of excess body weight over 24+ months
Operating Time1-2 hours1-2 hours
Recovery Time9-12 weeks2 weeks
Hospital Stay3 nightsLess than 24 hrs
Time off Work2-3 weeks1 week
ReversibleYesYes
Medical ImplantNoYes
How it
Promotes
Weight Loss
  • Restrictive & Malabsorption
  • Limits food intake
  • Reduces absorption of calories and nutrients
  • Restrictive
  • Limits food intake
  • Slows digestion
  • Creates fullness
Change
to Intestine
  • Small intestine is cut and bypassed during RNY gastric bypass surgery
  • No change to the intestine during gastric banding surgery
Change
to Stomach
  • New Stomach Created
  • Stomach is divided into a small upper pouch 1 oz (20-30 cc) and a larger lower pouch
  • Stomach Size is Reduced
  • An adjustable silicone ring (band) is wrapped around the top portion of the stomach creating a small 1-2 oz (15-30 cc) pouch
Bariatric Diet, Dietary Guidelines
  • 800 calories per day during weight loss (12-18 months)
  • 3 small protein meals per day
  • Avoid sugar and fats to prevent dumping
  • Avoid carbonated drinks
  • Drink 6-8 cups of water a day
  • Eat 1000-1200 calories per day after 18 months

  • 800 calories per day during weight loss (24-36 months)
  • 1000-1200 calories per day, once weight goal is achieved
  • Eat protein-rich foods
  • Avoid fibrous, dry, or doughy foods as they can get stuck if eaten
  • Avoid high fat and high calorie foods
  • Avoid carbonated drinks
  • Drink 6-8 cups of water a day
New Eating Habits After Bariatric Surgery
  • Eat small portions daily
  • Chew food throughly to puree consistency before swallowing
  • Eat slowly
  • Eat high-protein foods
  • No drinking with meals, drink water 30 minutes before or after meals
  • Requires specific post-bariatric surgery diet

  • Eat small portions daily
  • Eat 4-6 times a day
  • Chew food throughly to puree consistency before swallowing
  • Eat slowly
  • Eat high-protein foods
  • No drinking with meals, drink water 30 minutes before or after meals
  • Requires specific post-bariatric surgery diet
Bariatric Vitamins, Minerals & Nutritional Supplements
  • Multivitamin
  • Calcium
  • Iron
  • Vitamin B12
  • Folate
  • Vitamin A
  • Vitamin B1 (Thiamin)
Pros, Benefits, Advantages of
Weight Loss Surgery
  • Rapid weight loss during the first 6 months
  • Reduces food intake
  • Reduces calorie intake
  • Proven long-term effectiveness maintaining weight loss
  • Most common and widely accepted weight loss surgery

  • Simple and relatively safe
  • Reversible
  • Adjustable
  • Short hospital stay
  • Quick recovery period
  • Low malnutrition risk
  • Low rate of complications
  • Does not remove or alter any part of the stomach or intestines
Cons, Risks, Disadvantages of
Weight Loss Surgery
  • Blood clots
  • Bowel obstruction
  • Dumping syndrome
  • Infection
  • Leaks
  • Nutrient deficiencies
  • Reflux (GERD)
  • Ulcers
  • Band slippage (<5%)
  • Band erosion (<1%)
  • Band fill and adjustments
  • Infection
  • Port problems
  • Stoma obstruction
Am I a Candidate for Weight Loss Surgery?
  • Gastric bypass is most effective for patients with a BMI of 35-55
  • Gastric banding is best for patients who follow a strict bariatric diet and physical exercise program
Bariatric
Surgery Method		Laparoscopic Bariatric SurgeryLaparoscopic Bariatric Surgery
Learn More About Different Types of Bariatric SurgeryTypes of Bariatric SurgeryTypes of Bariatric Surgery

Gastric Bypass Surgery

Gastric Bypass Surgery not only helps patients lose more weight compared to lap band, but is also beneficial in resolving many obesity-related medical conditions. Patients who choose gastric bypass vs lap band surgery can lose 70% of their excess body weight within 12-18 months.

Lap Band Surgery

Lap Band Surgery, or Gastric Banding requires routine follow up for band adjustments compared to gastric bypass. Patients who choose lap band vs gastric bypass typically lose 40% of excess body weight gradually over time.

Compare Differences Between Types of Bariatric Surgery