Home Blogs Bariatric Surgery Bariatric Surgery Side Effects, Risks & Complications: Key Facts
Written By Anha Wahid Ansari
Bariatric Surgery
6 mins read
21/04/2025
If you’re considering bariatric care, then you might be curious about whether or not to expect any complications after weight loss surgery.
The surgery is usually safe. However, like any surgery, it can have complications and side effects, and sometimes may require another operation.
Furthermore, early complications and side effects can appear in the first week to months after surgery; on the other hand, late complications and side effects generally occur within a month to a year, yet the risk of developing some complications persists for life.
Read this article and learn about the possible complications and how to prevent them.
Bariatric surgery, commonly known as weight loss surgery, includes various surgical procedures aimed at helping individuals with obesity achieve weight loss. Healthcare providers may recommend this surgery if other weight loss methods have failed. Bariatric surgery functions by modifying the digestive system, primarily affecting the stomach and, in some cases, the small intestine.
With bariatric surgerymost people loose about 90% of their excess weight, yet different procedures can lead to different results like gastric bypass leads to a weight loss of about 70%, and the duodenal switch usually results in an 80% weight loss and with gastric sleeve surgery, weight loss varies between 30% and 80%.
It's a weight loss surgery involving various procedures such as gastric sleeve, gastric bypass, adjustable band, etc, however, each procedure has different side effects and complications. Let’s learn about the procedure and its side effects as well.
Gastric sleeve surgery, also called sleeve gastrectomy, is a weight-loss surgery designed to help people by making their stomachs smaller. In this procedure, doctors remove most of the stomach, leaving just a narrow tube or sleeve. This smaller stomach can help limit how much food you can eat and may also reduce feelings of hunger, making it easier to lose weight.
This procedure removes a large part of the stomach and leaves a narrow, sleeve-like shape that limits how much food you can eat. However, there are some common side effects to be aware of.
○ Dyspepsia (indigestion)
○ Abdominal distension (swelling or bloating)
○ Vomiting
○ Constipation
○ Diarrhea
○ Gastroesophageal reflux (GERD)
○ Abdominal pain
○ Nausea
In rare cases, surgery can cause:
○ hypoglycemia
○ hernia
○ stenosis (narrowing of the stomach)
○ gastrointestinal blockage (obstruction)
It’s a type of weight loss surgical procedure that creates a small pouch from the stomach and connects the newly created pouch directly to the small intestine.
This surgical procedure involves creating a small pouch that attaches directly to the small intestine, allowing food to skip over a large section of the stomach and digestive system.
While this can aid in weight loss, gastric bypass surgery has a higher risk of a condition known as dumping syndrome compared to other weight loss surgeries. Early dumping syndrome can lead to symptoms like nausea, weakness, and sweating shortly after eating.
‣ Bloating
‣ Cramps
‣ Dizziness
‣ Palpitations (rapid heartbeat)
‣ Fainting
‣ Nausea
‣ Vomiting
‣ Diarrhea
‣ Flushing
Late dumping syndrome develops 1 to 3 hours after eating and may lead to:
‣ Fatigue
‣ Tremors (shaking)
‣ Weakness
‣ Palpitations
‣ Fainting
‣ Sweating
‣ Flushing
‣ Dizziness
If it's left untreated, it may lead to malnutrition, and other complications include:
‣ Stenosis can cause dysphagia
‣ Marginal ulcers
‣ Cholelithiasis
‣ Small bowel obstruction
It's a device that is surgically implanted to help patients with obesity lose weight, and it's one of several types of bariatric surgery that restricts how much you can eat at one time.
This surgery involves putting a flexible band around the top part of the stomach, which creates a small pouch that helps control how much food you can eat at a time. Possible complications and side effects of the surgery include:
⦾ Nausea and vomiting
⦾ Constipation
⦾ Difficulty swallowing
⦾ Gastroesophageal reflux
⦾ Port problems
⦾ Outlet obstruction
⦾ Band sippage
⦾ Esophageal dilation or pouch dilation
⦾ Band erosion
⦾ Band intolerance
It's a complex weight loss surgical procedure that helps to reduce your ability to absorb calories, vitamins and minerals. However, you can lose more weight with the duodenal switch than with the gastric bypass or the sleeve gastrectomy.
It's a mixed surgical procedure that involves removing a large portion of the stomach and rerouting the intestines to reduce the absorption significantly, and here are some minor side effects, which include:
⦾ Diarrhea
⦾ Reflux
⦾ Bloating
⦾ Increased flatulence
Additionally, it is also associated with deficiencies in:
⦾ Vitamin A (retinol)
⦾ Vitamin E (tocopherol)
⦾ Zinc
⦾ Iron
⦾ Calcium
⦾ Vitamin B1 (thiamin)
⦾ vitamin B12 (cobalamin)
⦾ Vitamin B9 (folate)
However, if it's left untreated, ongoing deficiencies may lead to malnutrition. Yet, other common complications include:
⦾ Anemia
⦾ Osteoporosis (bone loss)
⦾ Gallstones
In rare cases, it can cause:
⦾ Bowel obstruction
⦾ Hernia
⦾ Anastomotic leak
To prevent the side effects, you need to follow the given guidelines, which will help you to understand what you should do and what you should not do:
Bariatric surgery is a life-changing procedure for individuals struggling with obesity and its related health conditions. However, it's important to be aware of the potential risks and how to overcome them. However, proper care, lifestyle changes, and regular follow-ups are important to minimise the risks and achieve long-term success.
Furthermore, by understanding these potential complications and how to take care of them, you can make informed decisions about the role of bariatric surgery in weight loss.
FAQs
It’s a weight loss surgery that involves various weight loss procedures such as gastric bypass surgery, gastric band, gastric sleeve, etc, to help patients with weight loss and its related health conditions.
Side effects include nausea, vomiting, diarrhoea, dumping syndrome, low blood sugar, malnutrition, etc. However, long-term risks include gallstones, hernias, and ulcers.
Malnutrition deficiencies after weight loss surgery occur due to a combination of factors such as reduced food intake, changes in digestion and absorption and inadequate supplementation. However, these deficiencies can affect both macronutrients, like vitamins and minerals.
Dumping syndrome is a condition that can happen after someone has weight loss surgery, like bariatric surgery. It occurs when food moves too quickly from the stomach into the small intestine.
Yes, hair loss is a common problem after bariatric surgery, which is often due to rapid weight loss and nutritional deficiencies.
To overcome the side effects of weight loss, you need to focus on dietary adjustments, staying hydrated and addressing potential complications such as dumping syndrome or nutritional deficiencies. You need to follow your surgeon's instructions carefully and have regular follow-up appointments to manage side effects.
Yes, weight loss surgery can significantly improve mobility by relieving stress on joints and the musculoskeletal system due to excess weight.
Yes, it's possible to gain weight even in 12 or 18 months, which can occur due to multiple reasons, such as overeating or a lack of regular exercise.
For adults, the age should be 18 to 65 years, and for adolescents, the surgery is only considered in cases of severe obesity or when other treatment options have failed to achieve desirable results.
After surgery, a special diet is recommended that is easy to digest:
‣ Weeks 2-4 : You can have pureed foods such as soft proteins, blended vegetables and yogurt, which are gradually introduced.
‣ Week 4 : You can have solid foods such as cooked vegetables, soft fruits, and tender meats can begin to be incorporated.
‣ Post 8 weeks : You can start eating regular solid foods that are protein-rich and low in fats and sugars.
Written By
I'm a content writer at Mejocare.com, where I create easy-to-understand and informative healthcare content. With 4+ years of experience, I help people learn about important health topics and connect with healthcare providers through clear and engaging writing.
I focus on making complex medical information simple and useful, ensuring that readers can easily find the answers they need.
What I do:
I’m committed to helping Mejocare share reliable health information with its readers.
SOURCE
HISTORY
At Mejocare, we prioritize accuracy and reliability. Our content is based on peer-reviewed studies, academic research, and medical associations. We avoid tertiary references. Learn more in our editorial policy. Trustworthy health information for you.
https://www.healthline.com/health/side-effects-of-obesity-surgery para no 2,3,4,5 https://www.mainlinehealth.org/blog/everything-you-need-to-know-about-side-effects-of-bariatric-surgery para no 1 https://mydoctor.kaiserpermanente.org/ncal/structured-content/possible-complications-and-side-effects-of-weight-loss-surgery-2490383 para no 1 https://my.clevelandclinic.org/health/treatments/bariatric-surgery para no 2, 9 https://my.clevelandclinic.org/health/treatments/22931-gastric-sleeve-surgery para no 1 https://my.clevelandclinic.org/health/treatments/17163-lap--band-surgery para no 2, 15 https://anandgastrosurgeon.com/common-side-effects-after-weight-loss-surgery-and-how-to-manage-them/ para no 10
CURRENT VERSION
Our care team can help you.
Shafaq Khan
Dr. Simran Rao