The Truth About Weight Loss Drugs: A Complete Guide to the Effects and Risks of Three Types of Medications

Weight Loss Through Medication

In daily life, many people feel that lifestyle interventions are too slow to be effective and look for shortcuts. They hear that weight-loss pills don't require exercise or dietary restrictions; you just take them, and the weight drops rapidly, so they want to try them.

So, can weight-loss medications actually help you lose weight? When should they be used?

The first type of weight-loss "medication": Health supplements claiming to aid weight loss

The most common weight-loss "medications" we see are various health supplements that claim to help with weight loss, such as detox teas and slimming teas.

These products are either based on false advertising and have no effect; or they secretly add laxatives, causing diarrhea, which might work in the short term but will harm your health; or they use the name "slimming" while adding health-promoting ingredients like cellulose and probiotics, but these are actually unnecessary for weight loss.

In short, for these products, just remember one thing—from the perspective of helping you lose weight healthily and effectively, they are almost useless. If you are still very curious about these health supplements, you can turn to Chapter 4, Section 5 for a complete explanation.

The second type of weight-loss medication: Professional weight-loss medications

Currently, professional weight-loss medications on the market can be broadly divided into three types:

The first type increases energy expenditure.

For example, Qsymia, a combination weight-loss drug approved by the U.S. Food and Drug Administration (FDA) in 2012. Its principle is to mimic sympathetic nervous system excitation, increasing the body's metabolic rate. 75% of people who take this drug can lose 8.8 kilograms in a year, and 54% can lose 10% of their initial body weight. Don't think this is too little; this is the most effective weight-loss drug to date. Even this effect is accompanied by a series of side effects such as indigestion, constipation, dry mouth, and insomnia.

The second type directly or indirectly reduces energy absorption.

For example, Orlistat, the only weight-loss drug approved for sale by the National Medical Products Administration of China. It works by binding to lipase in the gastrointestinal tract, preventing fat absorption. Among all weight-loss drugs, its weight-loss mechanism is the simplest, with almost no potential safety issues.

However, the actual effect is not what many people imagine as "food passing through without being absorbed." In fact, Orlistat can only reduce fat absorption by 30%. In other words, if you eat too much, the excess energy will still remain in your body, and you will still gain weight. Therefore, this medication must be combined with dietary management to be effective.

At the same time, because the ingested fat cannot be completely absorbed and must be excreted, fatty diarrhea is unavoidable, often resulting in embarrassing situations. Furthermore, some fat-soluble vitamins, such as vitamins A, D, E, and K, are very likely to be deficient and must be supplemented.

With so many drawbacks, how effective is it for weight loss? Data shows that within one year of taking orlistat,
44% of people can lose 5% of their initial body weight, an average of 26 kilograms. This number may disappoint many people.

The last, and newest, type of weight-loss drug is the glucagon-like peptide receptor agonist (GLP-1RA), with brand names including liraglutide, dulaglutide, and semaglutide, etc.

This drug was originally a hypoglycemic drug, but with increased research after its launch, it has brought unexpected weight-loss benefits to doctors.

First, its weight-loss effect is comparable to Qsymia, reducing body weight by about 10%. Second, its side effects are far less than the previous two drugs; the most common side effects are only nausea, abdominal pain, diarrhea, and constipation, and these are generally mild. More serious complications, such as pancreatitis, mainly occur in people who already have pancreatic disease.

The weight-loss mechanism of this drug includes two points: First, it acts on the gastrointestinal tract, delaying gastric emptying and intestinal motility; second, it acts on the central nervous system, suppressing appetite and increasing satiety. Both points are crucial and achieve the goal of reducing food intake.

However, although this drug has had excellent sales after being launched as a weight-loss drug, with sales quickly reaching billions of dollars, and I will try using it for my weight-loss patients when necessary, and the effect is indeed good, based on my own and my colleagues' clinical experience, I want to give you a very important tip: Patients using this drug almost always report having absolutely no desire to eat when they see food. For the average person trying to lose weight, this shouldn't be a problem. But what about those who are prone to depression or anxiety, or even suffer from clinical depression? This is what they told me: "Life is meaningless." For them, there's already so little joy left in life, and if they lose interest in eating as well, wouldn't life become utterly hopeless?

The scientific community is still unclear on exactly how these medications control appetite. However, we can be certain that the pleasure center is very close to the appetite center, with many overlapping pathways. Therefore, although there is no particularly clear evidence, I still want to raise this concern.