GLP-1 Agonists: What’s All the Fuss About?

There has been a lot of buzz around GLP-1, with medications like GLP-1 agonists e.g. Ozempic, Wegovy or Trulicity, frequently in the news.

So, what exactly is GLP-1 and what does it do for us?

Glucagon-like peptide 1 (GLP-1) is a gut hormone widely recognised for its role in blood sugar control, its ability to modulate insulin sensitivity, regulating appetite and supporting heart health.

There are multiple clinical benefits of GLP-1 Agonists

·       Assisting weight loss

·       Reducing inflammation

·       Reducing metabolic liver disease

·       Reducing diabetic kidney disease

·       Reducing atherosclerosis

·       Reducing myocardial infarction

There are several organs that play a role in the synthesis (creation), activation and action of GLP-1.

1.      Small intestine

2.      Pancreas

3.      Liver

4.      Brain

5.      Stomach

These organs all work together to ensure GLP-1 plays a key role in regulating appetite, blood sugar levels and body weight.

The cells in your intestines actually make GLP-1 agonists, and then they rapidly break them down.

1.      You eat food

2.      GLP-1 and other hormones are released in response

3.      Then it is broken down.

The GLP-1 agonist drugs prolong the action/life of GLP-1 in the body.

There can be problems or side effects with long-term use of GLP-1 agonist drugs:

·       They can be expensive

·       Some experience nausea, vomiting and/or diarrhoea

·       Low blood sugar (hypoglycaemia)

·       Serious complications include pancreatitis, bowel obstructions and gastroparesis

·       Due to lowered appetite there is a risk for developing dietary insufficiencies and nutrient deficiencies

How do we support our body’s ability to produce GLP-1?

An imbalanced diet, which can be a contributing factor to metabolic diseases like diabetes and obesity, can also lead to an imbalance in the gut microbiome (dysbiosis). This has several effects including:

·       Reducing your body’s ability to produce GLP-1

·       Increasing blood glucose

·       Increasing insulin resistance

·       Increased appetite and food intake

·       Low-grade systemic inflammation

Prebiotic fibres have a big influence on the microbiome. They help to feed the beneficial bugs of the microbiome and produce nutrients for the cells of your intestines, which leads to a healthier digestive system. Prebiotics are found in vegetables, legumes and some fruits, nuts and seeds. The intestinal microbiome also plays an important role in GLP-1 production by stimulating the bitter taste receptors in the gut.

We have 5 main tastes:

1.      Sweet

2.      Salty

3.      Sour

4.      Umami

5.      Bitter

Bitter taste receptors in the gut mucosa (gut lining) actually help control the release of GLP-1. These receptors are found not only on our tongues, but in our stomachs and intestines too. These get stimulated when we eat bitter foods such as rocket, radicchio, radish, lemons, grapefruit or other leafy green vegetables.

Our diets these days are lacking in bitter foods and we do have access to a lot of sweet foods, which we tend to overdo. The Mediterranean diet is very well researched and includes a lot of bitter foods. There are several studies now that have looked into the Mediterranean diets ability to increase GLP-1 [1].

To increase our own GLP-1 we need to eat more bitter foods like:

·       Grapefruit

·       Lemons

·       Radicchio

·       Rocket

·       Artichoke

·       Radish

·       Ginger

·       Fresh herbs like oregano and dill

·       Olives

·       Aperitifs

·       Leafy green vegetables

·       Buckwheat

·       Olive oil [2]

·       Cacao [3]

 In summary

·       Our bodies naturally produce GLP-1 and they are rapidly degraded

·       We don’t know yet the full effects of long-term use of GLP-1 agonist drugs which keeps GLP-1 in the body for longer

·       Eating bitter foods and a Mediterranean diet can promote natural regulation of hormones involved in digestion and regulate weight and blood sugar.

·       Having a healthy microbiome also contributes to the regulation of GLP-1. We can support this with eating prebiotic fibres.

References

 [1] Di Mauro A, Tuccinardi D, Watanabe M, Del Toro R, Monte L, Giorgino R, Rampa L, Rossini G, Kyanvash S, Soare A, Rosati M, Piccoli A, Napoli N, Fioriti E, Pozzilli P, Khazrai YM, Manfrini S. The Mediterranean diet increases glucagon-like peptide 1 and oxyntomodulin compared with a vegetarian diet in patients with type 2 diabetes: A randomized controlled cross-over trial. Diabetes Metab Res Rev. 2021 Sep;37(6):e3406.

[2] Cui M, Chen B, Xu K, Rigakou A, Diamantakos P, Melliou E, Logothetis DE, Magiatis P. Activation of specific bitter taste receptors by olive oil phenolics and secoiridoids. Sci Rep. 2021 Nov 16;11(1):22340.

[3] Kawakami Y, Watanabe Y, Mazuka M, Yagi N, Sawazaki A, Koganei M, Natsume M, Kuriki K, Morimoto T, Asai T, Arai H. Effect of cacao polyphenol-rich chocolate on postprandial glycemia, insulin, and incretin secretion in healthy participants. Nutrition. 2021 May;85:111128.