Women Are Using ChatGPT To Lose Weight—Here's How You Can Too

I never thought ChatGPT would be the tool that finally helped me lose weight, but here we are. Like a lot of women, I had tried all the tracking apps, but they always felt like a chore or were too expensive. So when I stumbled on a video by @cirstinagheicanu titled "How I lost 7kg with ChatGPT," I was so happy to see someone else doing exactly what I was doing. It reinforced that I was on the right track and reminded me that this tool really works. Many have realized that they can turn AI into a personal food log, macro calculator, and accountability buddy. Suffice it to say ChatGPT has worked better than anything else I’ve tried.

That said, here's how I used ChatGPT to help me lose weight and how you can too. This guide combines my experience, tips from other women like Cristina, and the smartest, most practical ways to make this AI work for you.

Step 1: Figure Out Your Calorie Deficit

The foundation of weight loss is a calorie deficit, which means eating fewer calories than you burn. ChatGPT can help you find this number in under a minute. So, before anything else, it’s important to understand your personal calorie deficit. That number becomes your north star for the rest of your tracking, whether you’re asking AI for food suggestions or logging meals throughout the day. Enter the prompt below so you can figure yours out.

Prompt: "Can you help me calculate my maintenance calories and create a calorie deficit for fat loss? I am [your age], [your height], [your weight], and [your activity level]."

It will run the math and tell you what your maintenance calories are. From there, it should subtract about 300–500 calories so you can start losing fat at a steady, sustainable rate. The deficit that it gave me is currently 1400 to 1500, so I try my best not to exceed those numbers.

If you don’t know your activity level: Just describe your typical week: "I go to the gym three times a week, walk 5,000 steps most days, and have a desk job." You can also log your workouts every day.

Step 2: Replace Complicated Apps With Simple Prompts (But Still Log Your Numbers)

Now that you know your number, you can start logging your meals into ChatGPT. Instead of spending 10 minutes entering every ingredient into an app, I just talk to the AI. Each morning, I send a message like:

Prompt: "Today I want to eat 1300 calories. I already had 3/4 cup Greek yogurt, 1/2 scoop whey protein, and 1/3 cup blueberries. Can you add this and show me what I have left?" I also add photos of nutrition labels, especially for anything new or packaged.

ChatGPT calculates my totals, shows me how much room I have left, and organizes it in a clean table so I can see at a glance what needs adjusting. It’s fast, flexible, and far less annoying than tapping through a dozen menus. If you want to be highly accurate, definitely invest in a food scale (but more on this later).

Step 3: Teach It Once, Reap the Benefits Forever

In the beginning, I had to teach it the macros of the foods I eat most. My homemade chicken salad. My bread recipe. The yogurt brand I use.

Prompt: "My chicken salad is made with 1.7 lbs of chicken, Greek yogurt, and avocado mayo. I get 5 cups total from this batch. Please remember that each 1/4 cup serving is 55 cal and 9g protein."

From then on, I could just say, "Add 1/4 cup chicken salad" and it already knew. This shortcut saved so much time.

It’s like having a custom tracker tailored to your kitchen.

Step 4: Use It All Day, Like a Thought Partner

Throughout the day, I check in like I’m texting a friend:

• After breakfast: "What’s my running total so far?"

• After lunch: "I have 500 calories left. Can you suggest a high-protein dinner using ingredients like eggs, chicken, and avocado?"

• At night: "Here’s what I ate today. Can you analyze if I hit my protein and fiber goals?"

ChatGPT, along with tracking your macros, gives suggestions and troubleshoots. If you want it to become your personal coach, you can tell it to be one. It'll hold you accountable when you ask it if you should have another cookie.

One time, I was constantly hungry and couldn’t figure out why. I asked ChatGPT to review my food log. It told me I was only getting 9g of fiber and suggested adding more veggies or seeds. The next day, I felt full and energized. That’s how helpful it is.

Step 5: If You Don’t Have a Food Scale Yet…

Start anyway. Seriously. I used ChatGPT to estimate portions in the beginning:

Prompt: "I had about 10 almonds, a spoonful of peanut butter, and a small banana. Can you estimate the calories and protein?"

It gave me a solid estimate using nutrition databases.

Once I got a $12 digital food scale, things leveled up. Suddenly I knew that my "spoonful" was actually 1.5 tbsp. That small banana turned out to be 120g. The precision helped me dial in my calories and hit goals faster.

You don’t need a scale to start, I promise, but if you really want to be accurate you’ll probably want one soon.

Step 6: Use Photos and Ingredient Lists for On-the-Fly Ideas

I sometimes send ChatGPT a photo of my fridge or pantry and ask:

Prompt: "What can I make with this? I have 600 calories left today and need at least 30g more protein."

Or I’ll drop a list:

Prompt: "I have eggs, avocado, canned tuna, rice, and lettuce. Make me a high-protein lunch under 400 calories."

The AI will give you real recipes with approximate macros.

Step 7: Use It to Plan and Prep Your Meals for the Week

Whether you’re trying to stay within your calorie deficit or just want to stop stressing about what to eat every day, ChatGPT can create meal plans tailored to your goals.

Prompt: "Can you make a 3-day meal plan that stays under 1300 calories a day with at least 100g protein per day?"

It’ll build a plan with breakfast, lunch, dinner, and snacks and even give you a shopping list if you ask for one.

Prompt: "Make a shopping list for this plan."

You can also use it for meal prep. If you already have a go-to dish (like a grain bowl or pasta bake), just give ChatGPT the ingredients and serving sizes, and it’ll help you portion everything out and calculate the macros per container.

Step 8: Teach It Full Recipes to Calculate Servings and Meals

This is one of my favorite ways to use ChatGPT. When I make something like butter chicken or Thai curry, I tell ChatGPT all the ingredients, how I cooked it, and how much it made in total.

Prompt: "I made butter chicken with 2.5 lbs of chicken thighs, 1 tbsp butter, 1 cup coconut milk, tomato paste, and spices. It made about 5 cups total. Please calculate the calories, protein, and fat per 1-cup serving."

Once it has that info, I can just say:

Prompt: "Add 1 serving of butter chicken"—and it remembers everything.

This makes batch cooking and leftovers so easy to track. I don’t have to re-input the recipe every time. Just one setup, and it's ready for the week.

Step 9: Stay in One Chat for Best Results

Cirstina and I both learned this: keep it all in one thread.

Every time you start over in a new chat, it forgets what you taught it. But if you stay in the same conversation, it remembers your usual foods, your daily targets, and your portion sizes. It’s like building your own private nutritionist who knows your routine.

Step 10: Ask It to Create a Workout Program Just for You

Movement matters, too. ChatGPT can help build a workout routine that fits your lifestyle, schedule, and fitness level.

Prompt: "Can you create a weekly workout plan for fat loss and toning? I can work out 3–4 times a week, and I like Pilates and strength training."

You can get as specific as you want. Whether you have access to a gym, prefer at-home workouts, or only have resistance bands, it will tailor everything to you. It can even break things down day by day:

Prompt: "Give me a 4-day split for glutes, arms, legs, and core with rest days in between."

Or ask for something minimal:

Prompt: "What’s a 20-minute full-body routine I can do at home with no equipment?"

Helpful Prompts to Steal

• "Make me a high-volume dinner under 500 cal with 40g protein."

• "I’m feeling really bloated today. Can you look at my food log and tell me why?"

• "I only have 15 minutes. Give me a quick dinner plan with what’s in my fridge."

• "Create a 3-day meal prep plan for 1300 cal/day with at least 100g protein/day."

• "Add this to my log: 1/2 cup white rice, 1/2 cup glazed carrots, 1 baked chicken thigh."

• "Here’s a list of what I ate today. Can you flag anything that might have hidden calories or be throwing off my macros?"

• "Calculate the dinner I made and tell me how much is in one serving [provide the ingredient list and the serving amount]."

Final Thoughts: Why This Works When Everything Else Didn’t

What made this process different for me was how intuitive it became. I was just talking to ChatGPT like a personal diary that happened to be really good at nutrition math. I lost weight because, for once, I was consistent. And I was consistent because this method was so simple and easy to do. If I had a higher-calorie day, there was no shame either. The AI would just provide suggestions and adjustments. If I had low energy, we reviewed my macros. Lastly, if I didn’t know what to eat or how much to eat, I asked for help.

So if you’ve been stuck, overwhelmed, or just bored of traditional trackers, try this. It might change everything.