Published: 12/07/2023

How Weight Loss Drugs and Low-Carb Diets Work Together for Patient Success 

Considering that about 70 percent of American adults are overweight or obese, it’s no wonder that the new suite of injectable weight-loss drugs such as those containing semaglutide or tirzepatide are piquing the interest of consumers and healthcare professionals.  

These medications, which were originally used to help control blood sugar in people with type 2 diabetes, have been shown to help people lose weight. Since this discovery, as well as recent approval by the Food and Drug Administration, prescriptions have increased 40-fold.  

How Do These Weight Loss Drugs Work? 

These medications mimic the effect of a hormones in the body, known as incretins. Their primary target is the glucagon-like peptide-1 receptor (GLP-1R), but some of the newer medications appear to also have affinity for other other satiety hormone receptors such as gastric-inhibitory peptide (GIP). Our current understanding is that these medications work by replicating the effect of satiety hormones naturally produced by the body, but to a much greater magnitude.   

One important caveat is that the GLP-1 that is released naturally in the body lasts mere minutes before it is broken down, whereas semaglutide and other GLP-1R agonists lasts about a week, and are present in circulation at much higher levels. Ultimately, this leads to a patient feeling fuller more quickly and longer as well as having less appetite, leading to weight loss due to decreased caloric intake. 

Weight Loss Medications and Diet 

The clinical trials which demonstrated the efficacy of GLP-1R agonists found that these medications are highly effective in reducing caloric intake. One common piece of knowledge in the weight loss space is that when caloric intake is reduced, nutrient requirements are often difficult to meet, meaning that eating nutrient-dense foods becomes a top priority. Eating well can be a challenge when experiencing loss of appetite or some of the common side effects associated with these medications, such as nausea, diarrhea, vomiting and constipation.  

Additionally, if the goal is to lose weight, it’s important that the pounds dropping off are mostly from fat and not lean muscle mass. Not only are muscles important for supporting strong bones and helping the body function, but maintaining muscle mass during weight loss helps preserve basal metabolic rate – a key component to long-term success in weight management. This is also crucial for older people in order to prevent the development of age-related sarcopenia. 

In addition to eating plenty of fruits and vegetables, which helps dieters get essential vitamins and minerals, patients taking semaglutide-containing medications or other GLP-1R agonists should prioritize:  

Protein. This powerhouse macronutrient serves a number of metabolic and health roles. It maintains muscle mass, supports immune system function and is a building block of many processes within the body. Numerous studies have examined the role of protein intake on maintaining lean mass when energy intake is reduced by ~500-750 calories per day, such as would occur when someone is taking a GLP-1R agonist. A recent analysis of the impact of protein intake on lean mass preservation concluded “older adults retained more lean mass and lost more fat mass during weight loss when consuming higher protein diets.” While other studies have found improvements in body composition due to retaining lean mass during energy restriction in young and middle-aged adults. 

Fiber. This type of carbohydrate  helps keep the gut healthy, which is especially important when experiencing diarrhea, constipation and other digestive issues. For patients looking to reduce constipation (which is more common on these medications than diarrhea), increasing the amount of insoluble fiber by eating more non-starchy vegetables may be an effective strategy.  

Hydration. GLP-1R agonists such as semaglutide work by suppressing hunger. However, they also have been reported to suppress thirst, indicating that special attention should be given to maintaining hydration status for anyone taking one of these medications.  

How Low-Carb Diets and Weight Loss Drugs Work Together 

Optimal protein diets, like Atkins, have been shown to help with fat loss while sparing lean body mass during periods of reduced energy intake. Low-carb diets are also helpful for blood sugar management, which is often the reason people are put on semaglutide-containing medications or other GLP-1RA in the first place. In addition, patients experiencing nausea from these medications can consume high protein mini meals to ensure they are getting enough protein and essential vitamins and minerals even when it is hard to eat.  

Helping patients become comfortable on a low-carbohydrate diet that prioritizes protein and fiber can help support semaglutide-containing medication weight loss plans. Such eating patterns also limit less nutrient-dense refined grains and added sugars, both of which can add calories. 

If patients feel the need to discontinue taking semaglutide-containing medications, introducing them to a lower-carb diet like Atkins 100 can help protect and promote their weight loss journey. Studies have found that losing weight is easier when following a low-carb diet, and that this diet helps stabilize metabolism during weight loss maintenance.  

Finding The Right Weight Loss Plan for Your Patient 

Being at a healthy weight is beneficial for health. If your patients have had a hard time with traditional weight loss plans, they may consider taking semaglutide-containing medications or other GLP-1R agonists. Remember – these medications do not replace a healthy eating plan, so giving them tools to follow a diet that will also aid in weight loss is important. Since low-carb diets provide important nutrients such as protein and fiber, as well as vitamins and minerals, GLP-1R agonists and the Atkins approach can go hand in hand.  

With Atkins, a low-carb lifestyle is as flexible and attainable as the patients wish to make it. There are three options, whether or not patients also take weight loss drugs, that can fit within a one’s goals and comfort levels with carbohydrate restriction. What’s most important is to find a plan that works best with your patient, and that is easy for them to stick to. Explanations of each of the three Atkins approaches, plus recipes, meal plans and more, are at