GLP-1 drugs such as Ozempic®, Wegovy® and Zepbound® have opened new doors for people struggling to lose weight. If you have started taking them or are exploring your options, you should know that these medications work best when combined with the right diet plan, and not as a replacement for it.
Without proper nutritional support, many people experience side effects, lack of energy, or weight gain.
That's why in May 2025, four of the country's leading health organizations published their findings Expert Nutritional Guidelines for people taking GLP-1. Your goal: to help you feel better, stay on track, and maintain your results long-term.
Here's why it's important, what the experts recommend, and how you can easily implement it in your daily life.
How GLP-1s support weight loss and health
GLP-1 drugs mimic a hormone that your body produces naturally. By binding to receptors in the gut, brain, pancreas and other organs, they help reduce appetite, curb cravings, slow digestion and improve blood sugar control. Some people also report better sleep, more stable energy and less inflammation.
Thanks to these effects, GLP-1 can lead to impressive weight loss. Clinical studies show that people can lose 5 to 18 percent of their body weight in just over a year. This is much more than what is typically only seen with lifestyle changes.
But everyday results do not always correspond to clinical data. More than half of people stop taking GLP-1 within a year, often due to side effects such as nausea, fatigue and constipation. For others, the weight they've lost plateaus or regains weight.
These challenges are not just about the medications. In many cases they reflect what is missing: Nutritional support.
How poor nutrition undermines GLP-1 progress
When your appetite decreases and side effects occur, it can be easy to eat too little. Although eating less is part of how GLP-1 works, not eating enough can hinder your progress.
Here's how inadequate nutrition can affect your results:
- Nutrient deficiency
Poor food intake, especially during nausea or diarrhea, can lead to deficiencies in nutrients such as iron, calcium, magnesium and B vitamins. These nutrients support energy, immunity and metabolism. If they are missing, you may experience fatigue, thinning hair, brittle nails, or constipation. - Muscle and bone loss
When you lose weight, you lose both fat and muscle. Without enough protein, your body may lose more muscle than it should, slowing metabolism and weakening your body. Bone density can also decrease, especially in women and older adults. - Dehydration and electrolyte imbalance
Nausea, vomiting and diarrhea increase the risk of dehydration. Low fluid intake can also lead to fatigue, constipation, kidney strain and irregular heartbeat. - Weight gain
GLP-1 reduces hunger but does not impart lasting habits. Without a plan to maintain a balanced diet, many people regain weight. A large study found that about two-thirds of the weight lost with GLP-1 was regained within a year of stopping the medication.
Because of these concerns, experts emphasize that GLP-1 is a tool and not the entire solution. Combining medications with a personalized nutritional strategy supports your health and helps ensure your results are long-lasting. So what does a good nutrition plan look like?
What the experts recommend and how it works
To help people succeed, four national health organizations – the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association and the Obesity Society – released expert nutritional guidelines in 2025.
Their recommendations are based on research showing that people who combine GLP-1 treatment with nutritional support lose more weight, have fewer side effects and are more likely to maintain their gains after stopping the medication.
Here are the top strategies and easy ways to apply them.
1. Prioritize protein
Why it matters: Protein helps maintain muscle mass and bone strength while you lose weight. It also helps keep you full and satisfied.
Here's how:
- Aim for around 80-120 grams of protein per day. Combine adequate protein intake with strength training to optimally protect the muscles.
- Add a source of protein to every meal and snack. Eat protein first at every meal to increase the likelihood of getting enough protein before you feel full.
- Choose lean options like eggs, chicken, fish, dairy, tofu and beans instead of red or processed meat. Options that give you plenty of protein in relatively small portion sizes include Greek yogurt, cottage cheese, and egg whites.
- Use protein shakes or bars if necessary (look for low-sugar proteins and at least 10 grams of protein per serving).
2. With nutrient-dense foods, every bite counts
Why it matters: If you have a reduced appetite, every bite should provide vitamins, minerals and fiber.
How to do it
- Follow the plate method: Fill half of your plate with non-starchy vegetables like leafy greens, peppers, or zucchini, and divide the rest of your plate between lean proteins and high-fiber grains.
- Use fiber-rich whole grains more often than refined grains (like white bread and processed snacks).
- Review your diet with a doctor to decide if supplements are necessary.
3. Avoid nutrient-poor foods that worsen side effects
Why it matters: High-fat and highly processed foods can trigger or worsen nausea and indigestion. Plus, they have little nutritional value and take up space over more nutrient-dense options, protecting you from nutrient deficiencies.
Here's how:
- Avoid fried foods and processed meats such as bacon, sausage, lunch meat and fast food. Instead, choose baked, roasted, or grilled proteins like chicken, fish, tofu, or nuts.
- Reduce sugary drinks and snacks.
- Choose gentle options like bananas, oatmeal, or broth if you experience nausea.
4. Eat small, frequent meals
Why it matters: Smaller meals eaten frequently throughout the day will help you reach your nutritional goals even if your appetite is limited.
Here's how:
- Aim to eat every 3-4 hours, even if it's just a snack.
- Try simple combinations of protein and carbohydrates: a protein shake with fruit, cottage cheese or yogurt, apples and peanut butter, half a sandwich and vegetable sticks, canned tuna with whole grain crackers and vegetable sticks.
- Use phone reminders or meal timers if necessary.
5. Stay hydrated
Why it matters: Nausea, vomiting, diarrhea, and signs of low hunger can increase the risk of dehydration. Dehydration can worsen constipation, deplete energy, and negatively impact kidney and heart health.
Here's how:
- Carry water or herbal tea with you throughout the day.
- Drink some fluids between meals to avoid feeling overly full during the meal.
- Try ginger tea, broths, or electrolyte drinks if you experience nausea or vomiting.
6. Build confidence in cooking over time
Why it matters: Cooking skills support long-term success by giving you more control over what you eat.
Here's how:
- Start by cooking one more meal at home every week.
- Rely on simple tools like sheet pan meals or one-pot soups.
- Using meal replacement products, such as those included in Nutrisystem meal plans, can help you practice balanced eating while developing the skills to cook more for yourself.
What about keto or intermittent fasting?
Some people combine GLP-1 with diets like keto or intermittent fasting. These approaches may work for some, but they can cause complications during GLP-1 treatment.
Keto is very low in carbohydrates. Because GLP-1 lowers blood sugar, this combination can lead to dangerously low levels. The keto diet's high-fat focus can also increase nausea and reduce fiber intake.
Intermittent fasting encourages long periods of time without food. Combined with reduced appetite, this can make it difficult to meet your nutrient needs and increase the risk of blood sugar drops and binge eating.
Instead, focus on balanced meals that you can stick to long-term. A regular nutritional routine that fits your lifestyle is more sustainable and supports long-term results.
Working with a nutritionist or healthcare provider can help you customize your approach and stay supported throughout your journey.
Conclusion: A smart nutrition plan helps GLP-1 work better
GLP-1 drugs can be an effective means of weight loss, but diet is still the basis for success. The right plan will help reduce side effects, protect your energy, and ensure that results last beyond taking the medication.
Nutrisystem's high-protein approach to weight loss with portion-controlled meals can get you started on developing healthy habits.
Remember: Healthy weight loss isn't just about eating less. It's about giving your body the nutrients it needs to feel consistently strong, energized and confident.
References:
- Expert Panel. Nutritional Priorities to Support GLP-1 Therapy in Obesity. Obesity. Published May 30, 2025. doi:10.1002/oby.24336
