How do weight loss drugs work? They either reduce the appetite, reduce the absorption of nutrients, or increase the amount of fat that the body burns.
Obesity is becoming a worldwide problem these days. It used to be only affluent countries that suffered from it, but now there are not many countries that are unaffected. Obesity is a difficult thing to measure, but it is generally assumed that a BMI of 25 and over is overweight, 30 and over is obese, and 40 and over is morbidly obese. We probably assume that the US has the highest number of obese people, but that is not actually true. The country with the most obese people is Nauru, where 61% of people are considered to be obese. Then, the top ten most obese countries are: Nauru, Cook Islands, Palau, Marshall Islands, Tuvalu, Niue, Tonga, Samoa, Kiribati, and Micronesia. The USA is number 12 with 36.2%. However, if you want to get technical, Narau has a population of 12,511 people, which means that 7,631 people are obese. The USA has a population of 332 million, which means that 120,184,000 people are obese. All of the top ten countries are Pacific Island countries and they are probably obese because of colonization. They used to live on a diet of fresh fish, meat, and local fruits and vegetables. After colonization, they live on Western diets of rice, sugar, flour, canned meats, canned fruits, vegetables, soft drinks, and beer. Mostly highly processed food.
These days, you can buy drugs that can reduce weight. These drugs are very expensive and they have a long list of side effects, but they do appear to be effective. They have become known as Hollywood weight loss drugs because of their usage by actors and celebrities. These drugs work in several different ways. Some of the drugs promote weight loss by more than one method, but all of the drugs either lower appetite, reduce absorption of fat and nutrients, or increase the amount of fat the body burns. Let’s look at them.
The first type of drugs work by reducing the appetite. This can be done in a few ways. The first way is by reducing a hormone called glucagon. Glucagon is made in the pancreas and it regulates blood sugar levels. It can tell your liver not to absorb glucose and to produce more glucose if the blood sugar level is low. Reducing glucagon results in a suppressed appetite, but nobody appears to know why or how. The second way is by acting on the brain. Some drugs increase the levels of neurotransmitters in the brain and when the level of neurotransmitters goes up, appetite seems to go down. Although, as with glucagon, people don’t really know why this is. Another way to reduce the appetite is to slow down the speed at which the stomach empties. If the stomach is fuller for longer, the brain doesn’t start sending hunger signals and people eat less.
Some of the drugs reduce the amount of nutrients that the body can absorb. This can be down by blocking the enzymes that break down fats. Lipase is an enzyme that is made in the pancreas and it breaks down fats into smaller parts so they can be absorbed through the intestine. Some drugs block this enzyme, which means the fats pass through the digestive tract without being broken down. Usually about 25% of the fat remains undigested. This can reduce the amount of calories someone takes in.
The last things some drugs do is to increase the metabolic rate. One of the drugs that increases the level of neurotransmitters in the brain also raise the metabolism, but again, no one is sure why. Another drug increases the activation of the melanocortin 4 (MC4) receptor in the brain, which has many functions, one of which is regulating metabolic rate.
These drugs have become famous very quickly and they do work, for the most part. Different drugs have different results, but obese people can lose several kilograms just by taking them. However, they don’t fix the underlying problems and when people stop taking the drugs, their weight comes back. The drugs also have a long list of side effects, ranging from constipation to liver failure. The drugs are also very expensive, so many counterfeit, and potentially lethal, drugs are appearing on the black market and the internet. A magic weight loss pill might be here, but it needs to be used alongside lifestyle changes, healthy eating, and exercise. And this is what I learned today.
Photo by Andres Ayrton: https://www.pexels.com/photo/anonymous-obese-lady-touching-stomach-in-gym-before-workout-6551130/
Sources
https://www.healthline.com/nutrition/weight-loss-medication#who-should-use
https://en.wikipedia.org/wiki/Melanocortin_4_receptor
https://www.healthline.com/nutrition/phentermine-weight-loss#what-is-it-used-for
https://worldpopulationreview.com/country-rankings/obesity-rates-by-country
https://healthcare-digital.com/hospitals/why-pacific-islands-are-most-obese-nations-world
https://www.bbc.com/news/health-67414203
https://my.clevelandclinic.org/health/articles/22283-glucagon
https://www.mayoclinic.org/diseases-conditions/type-2-diabetes/expert-answers/byetta/faq-20057955
https://www.mountsinai.org/health-library/supplement/lipase
https://www.mayoclinic.org/healthy-lifestyle/weight-loss/in-depth/alli/art-20047908