Losing Weight Too Fast After Bariatric Surgery

Woman measuring waist with measuring tape

We must manage expectations when discussing the weight loss process after bariatric surgery. For many, this includes discussing realistic goals for how much weight should be lost (and how quickly). We try to temper expectations. Sometimes, patients set unrealistic goals or those that would not be achieved for several years and this leads to frustration and a feeling of failure. However, patients often find, especially in the first few months after surgery, that they may be losing significantly more weight than they expect and more than we suggest in their postoperative packet. There are many possible reasons for this, and we delve into a few of them here.

Your Starting Weight

There is a broad spectrum of obesity. After all, obesity begins with a BMI of 30 but has no upper limit. As such, someone with a relatively lower BMI will naturally lose less weight than someone with a higher BMI and more weight to lose. For example, when we say you should lose between two and four pounds a week, this would be for somebody in the 30 to 40 BMI range. Someone above that range may lose more, especially in the early days. If you are losing significantly more than expected but are following your diet and still have much more to lose, you may be fine. Discuss this with your bariatric surgeon rather than scrolling through the Internet and making assumptions about your situation. Consider also getting on the Advanced Bariatrics and Surgical Specialists Facebook support group.

You Need to Eat More

Most bariatric surgeries offer hormonal appetite suppression and mechanical restriction created by reducing the stomach size. Patients undergoing the gastric sleeve or duodenal switch will almost always have lessened hunger. Gastric bypass patients will have a self-limiting condition known as dumping syndrome if they happen to eat high-fat and high-sugar foods. These limiting factors can often lead to under-eating. You must reach your caloric intake over the day. It may be difficult, and while you shouldn’t force-feed yourself, we do want you to follow the general guidelines after surgery.

You’re Drinking Water Within 45 Minutes of Eating

You have likely seen guidelines for consuming water after bariatric surgery. Remember, your stomach is tiny; any water consumption before or during your meal can fill the stomach and lower its capacity to accept food. As such, we suggest you refrain from drinking anything for about an hour after your meal. Drinking liquids after your meal can stretch your pouch and cause discomfort, which may trick you into eating less in subsequent meals.

You Are Exercising Too Much

Exercise is fantastic, but as with anything else in the bariatric process, there are limits to how much you should do. This is not only because you risk injury; over-exercising can also put you into a significant caloric deficit, which can be counterproductive over the long term. In essence, over-exercising can easily put you in a starvation state after bariatric surgery. Start slow and increase your exercise step-by-step. Remember to increase your hydration and caloric consumption to match your activity level. If you have any questions about appropriate practices, we encourage you to bring them up during a follow-up appointment with Dr. Chang.

You’re Not Taking Your Supplements as Directed

Bariatric surgery is all about regaining balance, albeit at a lower weight. However, the journey to get there has its ups and downs, and your body is constantly in flux as you lose weight. Taking supplements, from protein and vitamin D to B12 and daily multivitamins, is critical to ensure that your body receives the appropriate nutrition even if your calories are significantly restricted. As an aside, improper supplementation is also a leading cause of readmission to the hospital and significant postoperative complications, so be sure to stay on top of it.

Last but Certainly Not Least Is the Concept of Body Dysmorphia

This is where you look in the mirror, but rather than seeing a person who has lost a significant amount of weight on their way to success, you see someone who has failed, and you don’t recognize the extraordinary achievements you’ve made. Typically, patients who have a distorted self-image try to lose additional weight through more exercise and less caloric consumption. Unfortunately, this does little to improve their situation and instead creates a significant risk of an eating disorder that can be very dangerous.

Conversely, not exercising enough can also cause you to lose more weight since you aren’t building muscle mass. The metabolism is also very adaptable and will change based on the amount of exercise performed and calories consumed. While this may seem attractive, and you may think you will lose more weight, it ultimately leads to problems because you will gain weight more rapidly once you start eating more. Similarly, you may lose muscle mass and bone density, which can cause longer-term physical issues.

The Bottom Line

For some, losing weight rapidly is a vector of the amount of weight they need to lose in the first place. For others, losing too much weight may be related to physical or psychological issues or issues that must be resolved. Regardless of the cause, speaking to your bariatric surgeon to understand more and ensure you are on the right track is essential. Do not simply assume that losing more weight than you should is a good thing. It’s vital that you put yourself on track for the long term through healthy and measured weight loss.