You may have heard about GLP-1 (glucagon-like peptide 1) in the news and elsewhere. The first GLP-1 injectable medication (Byetta) was first approved by the FDA in 2005 to manage blood sugar levels in those with type 2 diabetes. It mimics a naturally occurring hormone that stimulates the pancreas to make more insulin after we eat. Food moving from the stomach to the intestine slows down with GLP-1, making us feel fuller for a longer period.

There has been much talk lately about the GLP-1 weight reduction drugs. But what is GLP-1? Are injections the only way to get GLP-1?

What is GLP-1?

GLP-1 is one of more than 20 peptide hormones our body makes to help regulate digestion and blood sugar as well as dampen our appetite by signaling to our brain that we are full.

How Does GLP-1 Work?

GLP-1 works in many ways. It sends signals to our brain indicating we are full and it is an appetite suppressant. It also slows down digestion, thus makes us feel full longer. The slowing of digestion also helps regulate our blood sugar levels.

What About GLP-1 Drugs?

GLP-1 drugs Ozempic and Wegovy (also known as semaglutide) are used to treat type 2 diabetes. Mounjaro and Zepbound (also known as tirzepatide) are used for weight loss.

• Ozempic: a once-a-week prescribed injection approved by the FDA in 2017 for the treatment of type 2 diabetes. It works by releasing insulin and reducing the production of glucose in the liver. In addition to managing glucose levels, because it makes you feel full, people may also lose weight.
• Wegovy: a once-a-week prescribed injection approved by the FDA in 2021 as a weight loss medication for people who are obese and overweight who have additional medical conditions.
• Mounjaro: a once-a-week prescribed injection approved by the FDA in 2022 that mimics not only GLP-1, but a second gut hormone, GIP. It is prescribed to treat type 2 diabetes and is an appetite suppressant that slows down digestion and makes people feel fuller for a longer period of time.
• Zepbound: a once-a-week prescribed injection approved by the FDA in 2023 for use in people who are obese or overweight with one or more health-related conditions. 
  
  

Do GLP-1 Medications Work?

GLP-1s serve several roles. Blood sugar is better controlled, weight loss occurs for most, food moves through the GI tract slower making us feel full longer, and risk of heart attack, stroke, and type 2 diabetes is lessened. Unfortunately, the effectiveness of the drug stalls after about one year. The body is being tricked to suppress appetite so fewer calories are consumed, resulting in loss of weight and muscle mass. But the body resists rapid weight and muscle loss, so signaling to increase appetite occurs despite continuing to administer the medication, resulting in some weight being regained. The body requires fewer calories because of the weight loss, but the appetite suppressant drug is fighting the body’s rapid weight loss by its increased desire to consume more calories, so we are hungry and eat more calories. Metabolism slowing down with the loss of muscle mass is another contributing factor to the medication no longer being as effective.

The decision to use a GLP-1 hormone medication for weight loss should be made between you and your health care provider, but consider the following:

People Stop Taking GLP-1 Medications

One deterrent of taking GLP-1 medications is the side effects some experience including nausea, constipation, diarrhea, fatigue, headaches, and vomiting, causing people to stop taking the medication.

A second deterrent of people taking GLP-1 medications is their effectiveness as previously mentioned. A third deterrent for successful weight loss using GLP-1 injected medications is its cost. Paying $1,000 or more a month out of pocket for a lifetime for these medications is unsustainable, particularly since their effectiveness is diminished after about one year.

Some of the weight loss people experience when taking GLP-1s is often times regained when people stop GLP-1 injections, causing disappointment and frustration for the user to say the least.

For the drugs to be effective, it is imperative that lifestyle changes of eating whole foods and exercise, which can boost GLP-1 levels, be included. As previously mentioned, GLP-1 suppresses the signaling of hunger to the brain. If a person stops taking the medication, the “food noise” returns. If eating whole foods and exercise were not included in the weight loss regime, it is likely the person will continue old food habits, and it is most likely the person will regain some of the weight lost and maybe even gain more when the medication is stopped.

GLP-1 – A Naturally Occurring Hormone

And here is the little-known secret. Our body naturally makes GLP-1! The hormone is released only when whole foods are eaten. The body will quickly absorb processed and ultra-processed foods because of their lack of fiber. However, our naturally occurring appetite suppressing hormone GLP-1, is secreted further down our digestive tract (ileum) – primarily stimulated by carbohydrates and fats, and signals fullness to the brain. Processed and ultra-processed foods, however, are digested before reaching the ileum that releases GLP-1, and the feeling of being satiated when eating ultra- processed foods does not occur.

Fiber is the Key

Foods that break down into soluble fiber including whole grains, greens, nuts, vegetables, avocados, fruits, beans and lentils, flaxseed, tofu, and tempeh all break down in the lower colon where GLP-1 is released. Would more people be motivated to eat a whole food plant-based diet (WFPB) if they knew the fiber in these foods naturally stimulates the release of GLP-1? Not only can eating a WFPB diet result in weight loss, but it can also slow down and reverse several chronic diseases and improve quality of life. 
For those already eating a WFPB diet, you have one more reason to add to your list of benefits—the release of GLP-1.