Calorie Deficit: What Is It and Is It Important for People Taking GLP-1 Medications?
With the rise of GLP-1 medications such as Ozempic, Wegovy, Mounjaro, and Zepbound, weight loss has become more achievable for many people than ever before. Recent clinical studies have shown that GLP-1 medications can reduce weight in people with obesity by 15% to 25%.
These medications significantly reduce appetite, slow digestion, and stomach emptying to help users lose substantial weight. GLP-1 also helps regulate blood sugar in people with type 2 diabetes and has shown promising results in managing other health conditions, such as cardiovascular disease.
Due to these remarkable results, many people assume that GLP-1 medications work independently of diet and lifestyle changes. You just take the medicine, and that's enough to lose weight.
Unfortunately, that is not true. While GLP-1 is effective in supporting weight loss, you still need to pair it with lifestyle changes like exercise and nutrition, and maintain a calorie deficit to lose weight.
In this article, we'll explore what a calorie deficit is, how GLP-1 medications promote weight loss, and whether creating a calorie deficit remains an essential part of achieving and maintaining your goals.
What Is a Calorie Deficit?
A calorie deficit simply means consuming fewer calories, a deficit of about 500 calories per day, than what your body burns to function optimally. It is consuming less than what you expend.
Your body performs many important functions, such as breathing, blood circulation, tissue repair, and food digestion. To carry out these functions, it requires energy (calories), which it obtains from food.
Creating a calorie deficit happens when you consistently take in less energy than your body uses to power its daily operations. When this gap exists, your body has to find an alternative fuel source, tapping into its stored reserves—body fat. Over time, this reliance on stored energy is what leads to weight loss.
Besides reducing portion sizes to create a calorie deficit, you can minimize processed foods and sugary drinks and consume nutrient-dense foods instead.
Exercises like walking and strength training also help burn more calories, increasing the calorie deficit. Therefore, combining exercise with healthy nutrition practices creates a calorie deficit for weight loss.
While GLP-1 medications support weight loss, a calorie deficit remains the foundation of weight loss. Without it, the body cannot break down stored fat, which leads to weight gain.
However, GLP-1 medications such as Mounjaro, Wegovy, and Zepbound can create a calorie deficit much more easily. They work by reducing appetite, slowing stomach emptying, and minimizing food cravings. As a result, you eat fewer calories and stay fuller for long periods as opposed to feeling hungry if you had relied on dieting alone.
Why Is a Calorie Deficit Important for Weight Loss?
A calorie deficit is crucial because it is the key component of the entire weight-loss process. When you burn more calories than you consume, your body has less energy. This forces your body to find energy to compensate for the difference. So it breaks down stored fat in your body, leading to weight loss over time.
According to studies, a calorie deficit of 300-500 kcal is enough to lose 1.1 pounds (0.5 kg) weekly.
Is a Calorie Deficit Important for People Taking GLP-1 Medications?
Yes, a calorie deficit is still essential for weight loss on GLP-1 medications. While GLP-1s suppress appetite and regulate blood sugar, they are tools that facilitate a deficit rather than bypassing the laws of thermodynamics.
GLP-1s work by slowing digestion and mimicking hormones that signal fullness, which naturally causes you to eat fewer calories. If you do not consume fewer calories than you burn, you will not lose weight.
For users with type 2 diabetes, excess body weight contributes to insulin resistance, making it difficult for the body to regulate blood sugar effectively. A healthy calorie deficit can help promote gradual weight loss, improve insulin sensitivity, and lower blood sugar levels, thereby reducing the risk of diabetes-related complications.
How GLP-1 Medications Create a Calorie Deficit
Glucagon-like peptide-1 creates a calorie deficit by making it easier to consume fewer calories. It does so through the following ways:
Appetite Suppression: GLP-1 is one of the best appetite suppressants. It acts on the receptors in the hypothalamus, the main part of the brain that controls hunger, to reduce appetite and increase satiety. As a result, you end up with a greater calorie deficit.
Slowing stomach emptying: It slows food movement from the stomach to the small intestine. This keeps you fuller for a long time and prevents post-meal blood sugar increase, which also reduces rebound.
Reduced food reward signaling: GLP-1 receptors in the brain's reward and motivation centers, like the nucleus accumbens, are believed to dampen the pleasure response to food, especially highly palatable, calorie-dense foods. Food becomes less compelling, so you eat less without feeling deprived.
Improved insulin/glucagon balance: GLP-1 stimulates insulin release and suppresses glucagon (a hormone that raises blood sugar). This leads to more stable blood sugar, which reduces hunger driven by glucose.
Can You Lose Weight on GLP-1s Without Tracking Calories?
Yes, you can lose weight on GLP-1 medications without tracking calories. These medications help reduce appetite, regulate hunger signals, and slow stomach emptying, which naturally makes you eat less. As a result, weight loss can occur even if you never count a single calorie.
While calorie tracking isn't required for weight loss, that doesn't mean nutrition no longer matters. GLP-1 medications work best with lifestyle changes that support your overall health.
Focus on eating enough protein to maintain muscle and keep you feeling satisfied, choosing nutrient-dense foods, and staying hydrated throughout the day.
Recommended Calorie Intake While Taking GLP-1s
There is no recommended calorie intake for those taking GLP-1. The exact number of calories needed depends on factors such as age, sex, physical activity, medical conditions, weight, and height.
However, the general rule of thumb for weight loss is to consume 500 to 750 fewer calories per day than your basal metabolic rate. Basal metabolic rate is the minimum amount of calories your body needs to function and maintain its basic processes, such as breathing, growth, and the repair of body tissues and blood circulation.
The daily recommended calorie intake allowance is 2,500 kcal for men and 2,000 kcal for women to maintain a healthy weight.
In addition to considering calorie intake, it is also recommended that you focus on nutrients when using GLP-1. This will help you avoid side effects associated with the medications, such as constipation and diarrhea, and help you get the most out of them.
Since GLP-1 quiets food noise, your diet ought to be intentional and nutritious with protein, carbs, hydration, and fiber.
Protein preserves muscle by ensuring that most of the weight loss comes from body fat rather than muscle. It also supports metabolism and promotes satiety and fullness, ultimately leading to weight loss. For protein, focus on chicken, eggs, cheese, and protein shakes.
Constipation is one of the side effects of using GLP-1. Adding fiber to your diet may help alleviate these effects. You can get fiber from leafy greens, whole grains, lentils, and berries.
To curb constipation, nausea, and diarrhea as side effects of GLP-1 medications, hydrate. Aim for eight glasses of water or unsweetened beverages per day.
Avoid empty calories, sugary food, and alcohol. Not only will they add nothing to your body, but they may worsen GLP-1's side effects, such as nausea, vomiting, and digestive problems. For instance, greasy food may cause nausea, and ultra-processed food may spike blood sugar, making it riskier for people with diabetes. Thus, instead of fried food, take chicken, Greek yogurt instead of ice cream, or grilled vegetables over raw salad.
How to Create a Healthy Calorie Deficit on GLP-1s
Creating a healthy calorie deficit is not starving. In fact, consuming very few calories can cause significant, quick, but unhealthy weight loss. Consuming very low calories, for example, less than 1200 per day, can lead to loss of muscle mass, metabolic slowdown, and severe fatigue.
There are two major ways to achieve a calorie deficit: diet and exercise. With diet, you adjust your eating habits. You can do so by reducing your daily calorie intake by 500 kcal.
Nutrient quality also matters at this point. Focus on nutrient-dense foods that keep you fuller and satisfied for longer, rather than high-calorie foods that are quickly broken down and leave you craving more.
A calorie calculator may help you calculate how many fewer calories you need per day. Once you get the exact amount, break it down across your daily meals. For instance, you may break down a 14000 kcal diet into a 280 kcal breakfast, 420 kcal lunch, 420 kcal dinner, and 280 kcal snacks and drinks.
Exercise that focuses on muscle building also increases the number of calories you burn. This increases your basal metabolic rate, which widens the calorie deficit. For example, walking for 45 minutes is said to burn 216 calories on average.
Signs You're Eating Too Few Calories on GLP-1s
Although fewer calories create a calorie deficit needed for weight loss, too few calories can harm your health. Below are signs that you are eating too few calories:
Low energy levels and constant fatigue
Dizziness
Lightheadedness
Muscle loss
General body weakness
Frequent headaches
Feeling cold
Constipation
Rapid weight loss
Hair loss
FAQs About Calorie Deficit for People Taking GLP-1 Medications
Below are the most frequently asked questions from people taking GLP-1 medications while in a calorie deficit.
Do I still need a calorie deficit on Ozempic/Wegovy/Zepbound?
Yes. A calorie deficit is still necessary for weight loss, even when taking GLP-1 medications. These medications are not magic pills. They need to be in a calorie-deficient state.
They help reduce appetite, increase fullness, and decrease cravings, making it easier to consume fewer calories. When you consume fewer calories and expend more energy, a calorie deficit is created, which is paramount in weight loss.
What happens if you don't eat enough on GLP-1?
Although GPL-1 reduces appetite, eating too little can lead to fatigue, dizziness, muscle loss, nutrient deficiencies, hair loss, headaches, constipation, and hormonal imbalances.
Aim to consume enough nutrient-dense foods to support your body's energy and nutritional needs to mitigate these effects.
What is the best diet for people on GLP-1?
There is no single best diet for people using GLP-1. However, the most effective approach focuses on lean protein, fiber, fruits, cooked vegetables, healthy fats, whole grains, and adequate hydration.
How many calories should I eat on GLP-1?
Calorie needs vary based on age, sex, weight, activity level, and health goals, even when it comes to patients using GLP-1. Most people benefit from a moderate calorie deficit of 500-750 kcal per day, rather than severe restriction, which is below the daily recommended amount.
For the exact amount, your healthcare provider or dietitian can help determine an appropriate calorie target to support healthy, sustainable weight loss.
Is a 500-calorie-a-day deficit safe?
For most people, a daily calorie deficit of about 500 calories is considered safe and sustainable for weight loss. It leads to approximately 0.5 to 1 pound of weight loss per week. However, individual needs vary, and larger deficits may not be appropriate for everyone.
Why am I not losing weight on GLP-1 medications?
Not losing weight while using GLP-1 can be frustrating. But it is common among those using these medications. You may not lose weight due to metabolic problems, lack of exercise to help you burn the extra fat, or a too-low dosage of the medicine that has not yet reached its full effect.
Poor sleep, stress, and underlying medical conditions can also cause a weight plateau.
Create a Sustainable Calorie Deficit with Expert Support
A sustainable calorie deficit is the foundation for achieving long-term weight loss. Without it, GLP-1 medications like Ozempic, Wegovy, Mounjaro, or Zepbound can't achieve their goal. These medications can help reduce hunger and cravings to support weight loss, but only when combined with healthy nutrition, regular physical activity, and a personalized weight management plan.
At NP2GO, we understand that creating a sustainable calorie deficit plan during your weight loss journey can be challenging. That's where our experienced nurse practitioners come in. They provide personalized guidance on GLP-1 medications, nutrition, exercise, and long-term weight management strategies tailored to your unique needs and goals.
Whatever GLP-1 medications you're using, we can help you. Schedule your consultation today and take the first step toward achieving sustainable weight loss and better health.
