1. Take her to various outdoor activities, such as mountain climbing, outing, cycling, swimming, badminton and camping. Nothing is more relaxing and free than sweating, turning activities such as eating popcorn and watching movies into more interesting outdoor activities.
Get rid of the habit of "taking you to eat delicious food", "I'll bring you snacks if you want" and "giving you a snack gift package on holidays". Usually, urge her to drink more water. It would be better if it was honey lemonade. Accompany her to buy more fruits, and let her get into the habit of eating less junk food at regular intervals for three meals. Don't mention barbecue hot pot for the time being. Within a month, your girlfriend will scream with joy.
2. Go shopping with her. If you meet a skirt that she likes very much but can't wear, your sister will be very upset. Don't show disgust or regret. Tell her frankly that every dress has its right person, even if she can't wear this one, she is still beautiful. Then when she changes a little, you give her great affirmation, even exaggerated surprise expression.
Girls are best coaxed. Sometimes when you are depressed, you will give up on yourself and eat too much, but the person you like says to yourself, God, you have lost a lot of weight. It looks so beautiful. I believe there is no girl who can't help smiling. Don't worry, she will stop trying when she feels satisfied. She will start to seriously examine her figure and start to move towards more beauty.
Having said that, I must remind the subject: don't overdo it! This sentence is too important to be said ten times.
Health is the background of all beauty. Of course you want her to be what you want. But most chubby girls have a sensitive heart. Please protect it and don't let it get hurt.