This is part 3 of my GLP-1s for weight loss series. The other posts in the series are:
- Part 1: What does every nutrition professional need to know about GLP-1s?
- Part 2: How can dietitians manage GI side effects from GLP1s?
- Part 4: What nutrition and lifestyle recommendations should be made for people taking GLP1 therapy?
GLP-1s change dietary intake and food behaviours. They induce meaningful impacts on total energy intake and food preferences. While researchers continue to actively investigate this area, they believe several mechanisms are involved.
The key reference for this series of posts is: Mozaffarian, Dariush, et al. “Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society.” Obesity Pillars (2025): 100181.
How do GLP-1s impact the brain?
Brain imaging studies have shown the GLP-1s induce changes in the regions of the brain related to appetite and rewards. These changes can reduce:
- Cravings
- Hunger
- And increases in fullness
How do GLP-1s impact disordered eating patterns?
GLP-1s may benefit disorder eating patterns by reducing food pre-occupation and emotional eating. People have also reported increased eating control, reduced sweet cravings, and improved symptoms of food addiction.
How do GLP-1s impact food preferences?
Studies have found that GLP-1s tend to decrease cravings and interest in:
- High fat foods
- Sweet or savory foods
- Dairy products
- Salt or spicy foods
- Starchy foods
Studies have also found that GLP-1s tend to increase interest in:
- Minimally processed foods
- Nutrient-dense foods, such as fruits and vegetables.
Does dietary counseling change food intake for people who are taking GLP-1s?
One study demonstrated that dietary counseling increased protein intake and decreased added sugar intake.
How do GLP-1s impact nutrition-related quality of life?
(This is my term, as opposed to the authors term – for more about how I define nutrition related quality of life, check out my previous post here).
GLP-1s can impact nutrition related quality of life in several ways. For people who are experiencing nausea or GI symptoms, GLP-1s may make eating difficult and less enjoyable. In these instances people may be more likely to navigate to “comfort foods” that feel more settling in their stomach. It may also cause people to have longer periods between meals. For strategies to help manage nausea with GLP-1s, check out my previous post here.
In other instances, people who are experience reduced interest in food can experience frustration or sensations of loss due to the reduced pleasure they experience from food. This can have impact on their social interactions and hobbies (For example for people who enjoyed cooking). These symptoms may warrant referral to behaviour therapy or changes in dose or agent.
Want to know more?
Up next in the series: Part 4: What nutrition and lifestyle recommendations should be made for people taking GLP1 therapy?
Find the other posts in the series here:
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