GLP-1 drugs, first used to manage diabetes, were derived from Gila monster saliva.

A 201-level at how GLP-1 drugs lead to appetite reduction

It's well-established that drugs which mimic the hormone GLP-1 can help people lose weight and control blood sugar levels, primarily through appetite reduction. This technical review provides an overview of how both natural and therapeutic GLP-1 interacts with the gut and brain to produce its effects.

Diabetes drug GLP-1 is a peptide (that's what the 'P' is for).

GLP-1 drugs are under investigation for treating Alzheimer's, Parkinson's, and drug addiction

Researchers are investigating GLP-1 applications for a variety of chronic conditions. One area of interest stems from how study participants using GLP-1 for diabetes and obesity reported describing less longing for wine and cigarettes while taking the medication—intriguing researchers about using the drugs for addiction applications. The drug, they theorize, could bind to receptors that mediate desire. (Some users may experience a paywall.)

GLP-1 helps reduce obesity through a number of mechanisms

Clinical studies show GLP-1 drugs, including semaglutide, promote weight loss through a number of effects. These include reduced appetite, slower emptying of the digestive tract, increased insulin production, and more.

GLP-1 drugs mimic a natural hormone that triggers appetite-suppressing effects

Ozempic, one of the brand names for the drug semaglutide, was originally developed in 2012, to help treat Type 2 diabetes. Among other effects, the drug mimics a naturally produced hormone known as GLP-1, which is released while eating to let our bodies know we are full.

See which GLP-1 drugs are currently approved (along with their cost)

Around 75% of prescriptions for GLP-1 drugs are used to treat diabetes, while the remainder is used for weight loss. This overview from GoodRX includes a list and overview of currently available options along with prices for each.

Food companies are exploring 'GLP-1 friendly' diet labels

Producers of foods like Healthy Choice frozen meals are placing "GLP-1 friendly" labels on their food, but there's no regulation about what that label means. Nutritionists say that GLP-1s can help reduce appetite, but healthy, balanced diets are a necessary complement to the medications. Data shows that about half of GLP-1 users quit these medications within a year and then rapidly regain weight, underscoring the importance of also prioritizing healthy eating.

Semaglutides, which belong to a class of drugs called GLP-1s, are prescribed for weight loss in combination with diet and exercise because they trigger the release of the appetite-suppressing hormone incretin.

Debunking myths about weight loss drugs

Business Insider delves into the research on GLP-1 to highlight the good and bad aspects other stories overlook. Few make it clear that GLP-1 drugs simply don’t work for many people. This deep dive raises a number of questions about the future of GLP-1 and how they will be used.

GLP-1s are netting interest for treating autoimmune diseases, but are considered experimental

Already used to treat type 2 diabetes, the novel medications are showing some early promise in experimental studies at reducing inflammation and treating autoimmune conditions including rheumatoid arthritis and inflammatory bowel conditions. But researchers caution that side effects are still under investigation—rarely the medication has caused lupus, an autoimmune disease.

When people stopped using GLP-1, they regained two-thirds of the weight back.

What do people do once GLP-1 medications succeed at weight loss?

The drugs have been adopted by 1 in 8 Americans, with many achieving their prescribed weight loss. They now face the question of how to keep the weight off, the key issue with any weight loss program that researchers have known about for decades. Each case is unique. Some folks continue to use GLP-1s like Ozempic in minuscule doses, while others taper them off over time.

Read the FDA's statement on concerns over compound pharmacies

GLP-1 drugs popularity for weight loss and treating diabetes, led to a significant supply shortage and the rise of compound pharmacies, which produce customized drug formulations but lack formal approval from regulators. The drugs are ostensibly the same, but manufacturing methods lead to variations in concentration, filler compounds, and more.

The lack of guidance on getting off GLP-1s leaves patients at risk

Dr. David Kessler, former FDA Commissioner and public health leader, explores how these drugs override the brain’s reward-driven eating habits but have notable side effects. These include developing eating disorders, muscle loss, and intestinal obstruction.

GLP-1s are linked to reduced worker illness and cost savings—a 2026 economic analysis finds the weight-loss drugs are tied to a 17% drop in worker sick leave days.

In 2023, Americans spent more than $50B on weight loss drugs, a number expected to triple or more by the end of the decade.

Telehealth demand for GLP-1s is on the rise as people seek it out for myriad reasons—the proportion of non-obesity and non-diabetes-related prescriptions for the drug soared from 4.5% in 2018 to 17% in 2023.

12% of adults were taking injectable GLP-1 for weight loss according to 2025 survey

Weight loss injectable use rose sharply between 2024 and fall 2025. The percentage of adults who reported taking this class of medicine specifically for weight loss increased to 12.4%, compared with 5.8% in February 2024 when Gallup first measured it.

GLP-1s may lower inflammation, possibly helping to combat cognitive decline

An analysis of existing GLP-1 research, published in April 2025, indicated that GLP-1 drugs reduce inflammation, with numerous health benefits. The work notes that GLP-1s were linked with a statistically significant reduction in dementia in randomized clinical trials.

Risks of GLP-1s include health side effects, counterfeit drugs, and more

This episode interviews researchers and patients who have used semaglutide to explore some of the potential risks associated with using the drug to lose weight. These include insurance challenges, health scares related to counterfeit versions of these drugs, and some users lose their ability to enjoy food.

Tirzepatide: A GLP-1 drug that also acts on separate receptors to promote weight loss

Tirzepatide, like semaglutide, is a GLP-1 drug used in diabetes treatment and for weight loss. Unlike semaglutide, it also acts on glucose-dependent insulinotropic polypeptide receptors, proving a second route to reducing appetite as a means to treat diabetes and promote weight loss.

Peptides like GLP-1 account for 31 of 370 new drugs approved by the US FDA between 2016 and 2023.

Early peptide research focused on isolating the substances from animal tissue

In the first half of the 20th century, peptides including insulin and adrenocorticotropic hormone were isolated from animals to provide life-saving medicines. ACTH was isolated from the pituitary glands of cows and pigs and insulin was isolated from the pancreas of dogs and cows.

Medicare in early 2026 did not pay for GLP-1 for obesity treatment, and coverage under Medicaid varied widely by state.

Insurance coverage for GLP-1s remains uneven, but Medicare began covering it in some instances in July 2026.

How semaglutides are both better and worse than we know

The drugs were developed for use treating diabetes and, later, weight loss, but they have proven helpful with the heart, kidneys, and colon. On the flipside, it may slow digestion and lead to gastroparesis, or stomach blockages, and unexpected babies resulting from the slow effect of birth control pills.

GLP-1s may weaken the effectiveness of birth control and affect other medications, hindering how and when they circulate through the blood.

See the first dog ever treated with insulin—a peptide

Frederick Banting and his graduate student Charles Best were the first to isolate the peptide insulin from dogs. They induced diabetes in the animals and then treated them with this peptide.

Can you microdose GLP-1 agonists like Ozempic?

GLP-1 agonists like Ozempic can help with weight loss, diabetes, and anti-inflammation. For some users, normal doses are too much. So, they've started "microdosing"—taking a smaller amount than the lowest increment of the drug available. While not yet backed by clinical trials, some doctors observed positive effects for certain people.

The pancreas releases digestive enzymes and regulates blood sugar

The pancreas weighs about the same as a deck of cards and is smaller than the average adult human hand. This lopsided glandular organ controls blood sugar levels through insulin production and helps the body digest food by creating a neutralizing tonic filled with digestive enzymes.

In June 2026, EU food safety regulators approved sales of a GLP-1-inducing food additive, a change that may lead to 'supercharged' cereals and breads in Europe within a year. (free w/email)

Not everyone who is a candidate for GLP-1 is choosing to use the drug

One person writes about why, although she's a good fit for the medication on paper, she's decided not to take GLP-1 due to concerns about mental health and other side effects, among other reasons.

Companies developing new weight loss drugs

In recent years, weight loss drugs made a tremendous amount of money for Novo Nordisk and Eli Lilly. Other companies are developing new drugs to break into the market. This piece is a concise overview of companies creating and testing new drugs, how far along they are, and what Novo Nordisk and Eli Lilly are doing to compete with these emerging rivals.

Diabetes is a hormonal disorder that occurs when the pancreas does not produce enough of a hormone that regulates blood glucose, called insulin, or when the body cannot effectively use the insulin it produces.

The popularity of new weight loss drugs has led to a diabetes treatment shortage

The FDA approved Ozempic to help patients with diabetes, but the popularity of semaglutide as a weight loss drug led doctors to prescribe Ozempic to nondiabetic patients who needed to lose weight. Ozempic became so popular that manufacturers could not keep pace with demand, posing risks for Ozempic-users with diabetes.

Insulin is a hormone that controls blood sugar by helping absorb it into cells

Blood sugar levels increase after a meal when the body starts turning food into usable fuel—sugars, proteins, and more—which are absorbed into the bloodstream through the intestines. Blood sugar levels rise, releasing insulin, and letting sugar in the blood be absorbed into hungry cells, thereby dropping blood sugar levels.

Semaglutide treatment extended the lifespan of female mice by about 12% in research published in 2026.

Peptide research dates back to the late 1800s

Peptide science dates back to the late 1800s with some early peptide synthesis work, but peptides took off in the medical sphere after surgeon Frederick Banting and his colleague's isolation of insulin from dog pancreases in 1921.

Snake venoms are repurposed proteins responsible for other bodily functions

Just as saliva aids digestion in humans, proteins responsible for bioactivities such as digestion and blood clotting were eventually secreted in the glands and fangs of snakes across evolutionary history. Organisms that could not withstand the effects of these molecules (e.g., excessive bloodstream clotting) became ideal prey for snakes.

The discovery of insulin led to a controversial Nobel Prize in 1923

For centuries, Type 1 diabetes was fatal. The 1920s "discovery" of insulin netted two of its creators—Frederick Banting and his boss, John Macleod—a Nobel prize. Separately, the German doctor Georg Zuelzer synthesized an effective version of the life-saving drug years earlier but was interrupted by World War I.

Understanding insulin

Scientists Daniel and Kelly talk with researcher Dr. Katrine Whiteson about diabetes, the history of insulin production, and Dr. Lydia Villa-Komaroff—an essential member of the team who discovered that bacteria could be induced to produce insulin. Listen to discover interesting facts about the life-saving medicine and how it works in the human body.

Diabetes 101: Insulin deficiency leads to high glucose levels in the blood

Glucose, the brain's preferred energy source, enters the bloodstream when the body breaks down consumed carbohydrates. To manage this increase in readily available energy, the body releases the hormone insulin, which allows glucose to enter and fuel our cells. Without insulin, glucose remains in the blood, causing health issues.

Leonard Thompson was the first human to receive an insulin injection for diabetes

In January 1922, the 14-year-old was the first person to receive an insulin injection to treat diabetes, just months after insulin was isolated in dogs and used to treat their induced diabetes. Thompson had an allergic response to an apparent impurity in the injection, but his second dose, 12 days later, was a success.

How weight loss drugs could reduce obesity costs

A detailed analysis from finance giant ING finds semaglutide and other weight loss drugs could significantly drive down global costs stemming from heart disease and other health problems associated with obesity. The benefits will vary, depending on each country’s demographics and drug and healthcare costs.

Weight Watchers began offering access to GLP-1 weight-loss medications in 2023 after losing more than 1.5 million members over the previous two years.

Overmedication has put type 2 diabetics at risk of low blood sugar

Type 2 diabetics in the US risk dying from low blood sugar, an epidemic traced to a decades-old, multi-million-dollar drug industry campaign encouraging an average blood sugar level below 7%. Contemporary research correlated such levels with reduced risk of eye, nerve, and kidney damage and increased hypoglycemia risk.

Explore different pig-to-human xenotransplantation possibilities, including using pig pancreatic cells for treating diabetes.

How to properly use semaglutides

This podcast with a nutritionist and a medical doctor discusses how useful semaglutide can be for weight loss. It also outlines the need for patients to set reasonable expectations and to make changes to both diet and exercise as part of an overall weight management strategy. The experts note that failure to make meaningful changes outside of using semaglutide may mean patients need to stay on the drug in order to keep the weight off.

Neural replays in mice help explain food aversions

Princeton University scientists published research in 2025 analyzing how mice learn to associate certain foods or flavors with feeling ill—even when there’s a time gap between eating something and feeling sick. The work, performed with grape Kool-Aid and injections of a substance that made mice sick, traced the literal “gut reaction” of how gut distress signals are linked to neural replays of what the mouse ate.

How Gleevec transformed leukemia treatment and cancer research

An outline of the discovery of imatinib (Gleevec), a ground-breaking drug that transformed the treatment of chronic myelogenous leukemia and sparked the beginning of precision medicine.