Dr. Tan Chun Hai, Debunking Common Weight Loss Myths & Misconceptions

Dr Tan Chun Hai is a General Surgeon practicing at Gleneagles Hospital Singapore. His subspecialty clinical expertise includes the use of keyhole or minimally invasive surgery in Bariatric and Metabolic Surgery, Stomach or Gastric Cancer Surgery. He is also well versed in Emergency and Acute Care Surgery for the abdomen and general surgical conditions. We had the opportunity to have Dr. Tan Chun Hai debunk some of the common weight loss myths & misconceptions for our audience. Learn more about Dr. Tan Chun Hai here

Q1) Can I eat whatever I want after a bariatric procedure and continue to lose weight?

Dr.Tan Chun Hai:

So, I usually say to my patients that the bariatric procedure is not a magic bullet. It is a lifelong process. Obesity is classified by WHO (World Health Organization) as a chronic relapsing disease, which means that even after a bariatric procedure, it is advisable to still keep to a healthy dietary and lifestyle changes to achieve the maximum result. Here, we have a dietitian as well as a physiotherapist to help our patients achieve their goals and guide them along the way, even after the surgery.

Being able to eat whatever you want after a bariatric procedure, and still lose weight, may be true to a certain extent, but only in the beginning because of the effect of the surgery. You see, a patient usually has poor results over a medium to long term because of weight regain and failure to adhere to dietary and lifestyle changes. Thus, even with adequate weight loss in the beginning, they are predisposed to poor weight loss and weight regain after surgery.

Q1.1) So will the weight regain be more than the initial weight before the procedure?

Dr.Tan Chun Hai:

It is possible. I have seen some patients that are not compliant to our advice that the weight regain actually goes back to even higher than their original preoperative weight.

Q2) Does eating late at night make me fat?

Dr.Tan Chun Hai:

I think there are a few parts to this statement. One part is ‘eating late at night’. The second part is ‘eating late at night makes me fat’.

I'll address the first part. Eating late at night does not correlate directly to making you fat. Weight gain and eating late at night are two separate issues. So, what makes you fat is when you have a positive energy balance. When you have a positive calorie intake with your net of your total expenditure, then essentially you'll be putting on weight over a long period of time.

Now, the second part, ‘eating late at night makes me fat’. We associate eating late at night with unhealthy living habits and eating unhealthy food. So, I think the general consensus is that the people who usually stay up and eat late at night usually eat foods that have more fat and are carbohydrate loaded, like junk food and fast food sweetened beverages. That's why there's an association with eating late at night- or eating dinner in general- causing weight gain.

I think a concept for improving your lifestyle is, if you want to have some snacks at night, choose healthy snacks and look carefully at the choices that you put into your stomach. Also, there are instances in which a patient fasted the whole day, didn't eat breakfast or lunch, and had a late dinner. That does not equate to eating late at night, making the patient fat. It still comes back to energy balance and the total intake versus the total expenditure that will cause the patient to be fat.

Q3) Does junk food make me fat?

Dr.Tan Chun Hai:

That is true. We correlate junk food with fast food like fries, potato chips, sweetened beverages, and other fried foods. So, essentially, the reason why junk food makes people fat is that their content is fat loaded and mainly carbohydrates. The more of this type of food content you consume, the higher chance that you'll be putting on weight. Because junk food does not feel like real food in your stomach, you end up eating more of the same amount of food.

Also, junk foods tend to have high sugar or high salt content. We have people who are very addicted to these sweet beverages and salty foods that they end up eating more of these, which then contribute to this vicious cycle of eating more junk food, contributing to weight gain.

Q4) Is liposuction a better alternative than bariatric surgery?

Dr.Tan Chun Hai:

Liposuction and bariatric surgery are two different procedures.

Liposuction is the removal of fat below the skin level. This is considered cosmetic surgery.

On the other hand, bariatric and metabolic surgery is a medically indicated surgery that helps the overall hormonal and body system to achieve weight loss. This involves reducing the amount of food that a patient can take in because of the volume reduction in the stomach.

More importantly, bariatric surgery also alters the set point in which the body views weight as a baseline. After surgery, the patient has an altered setpoint, which allows weight reduction to continue without the body using its mechanism to fight back the weight loss. Also, bariatric surgery decreases the appetite of the patient resulting in the patient requiring to eat less.

It contributes to not just weight loss, but also improvement in their comorbidities. We can see improvements in medical conditions like sleep apnea, diabetes control, cholesterol control, high blood pressure control. It also has positive psychosocial effects. They have a better mental well being and are able to perform their daily tasks in a happier mood.

Q5) Will I develop health issues due to vitamins & minerals deficiency after weight loss surgery? Is being obese less risky as compared to undergoing surgeries?

Dr.Tan Chun Hai:

Okay, so I think there are two parts to that question. Number one is the worry about nutritional deficiency after bariatric surgery and the second part is that being obese is less risky than undergoing surgery.

So, to answer the first part, even before bariatric surgery, most obese patients already have existing nutritional deficiencies, it's just that they're not diagnosed or have not discovered it yet. Now, we can offer replacement for some of these nutrients. Also, after bariatric procedures, we look out for these multivitamin or particular vitamin deficiencies that we can replace, which is why we work together in a multidisciplinary team.

Together with an endocrinologist, dietitian and your surgeon himself, we actively look out for these forms of nutritional deficiencies that we can actively replace. Of course, change in lifestyle as well as the dietary intake is also needed to offer nutrition replacement, on top of pills replacement after bariatric surgery.

Some procedures such as the gastric bypass are more prone to nutritional deficiencies compared to sleeve gastrectomy. But we will offer screening and offer a lookout for these nutritional deficiencies after bariatric surgery.

In response to the second question, that's a common myth most people think, that bariatric surgery is not safe and being obese is okay. We have long term studies, from multiple sources throughout the world, saying that being in the overweight and obese category over a prolonged period of time actually puts the patient at higher risk of sudden cardiac death, heart attack, and other obesity-related comorbidities.

Data from North America have shown that bariatric surgery is as safe as the most common procedures that we perform, such as gallbladder surgery or knee replacement. So, this refutes the view by the public of bariatric surgery as a high-risk surgery, and we have data to prove that bariatric surgery is safe. They are done by properly trained bariatric surgeons in a place that can offer them facilities to treat obesity.

There are long term studies that show that patients who undergo bariatric surgery are actually at lower risk of developing comorbidities associated with obesity compared to those who do not undergo surgery. Also, there is up to 30 to 40% risk reduction over a period of 15 to 20 years of sudden cardiac death, stroke, heart attack, and related conditions.