They noticed a significant change
The human brain notices new patterns and usually ignores similar and repetitive ones. When a person notices that someone’s weight changed greatly he might connect about it or make a remark.
They are jealous
Jealous people usually try to find anything bad about the ones they are jealous of then use those bad things to hurt them. A jealous person might make a remark about someone’s weight as soon as he notices a change.
To make people feel bad
Some people, who aren’t mentally stable, use such remarks to make people feel bad about themselves. Hatred is one of the possible reasons that motivates others to make bad remarks about others’ weight.
They pay a lot of attention to their own weight
Psychologists say that a person who is very focused on something is very likely to notice it everywhere. A person who is very concerned about his own weight will always note the change in weight of his friends and peers.
They can’t change their body shape
People who are too lazy to change their body shape might feel good when they find that an athletic person has gained a lot of weight. Those people usually make remarks about that person’s weight to feel good about themselves.
To compliment others
Some people make remarks about the weight of others to compliment them. While those people always have good intentions sometimes their remarks are perceived negatively by others if they said what a person didn’t want to hear.
To motivate someone
A person might make a remark about the weight of a close friend or an acquaintance to motivate them to either gain or lose weight. Even though those people might have good intentions such remarks usually hurt the person receiving the comments.
To feel superior
A person can make a remark about someone’s way to show how good he is. By comparing his progress to the progress of a person who has a weight problem that person usually feels better. (See Why do people strive for superiority?)
It’s a perception error
Humans can do many perception errors. The change in light settings or any other factor might force a person make a perception error.
They haven’t seen you in a long time
If a person didn’t see someone for a long time then they are more likely to notice that the changes that happened over the large period of time. Small day to day changes are usually ignored by most people.
They are trying to help
Sometimes a person might feel like pointing the attention of their friends to the changes in their body shape in order to help them take care of themselves. (See Why do some men scream while lifting weights?)
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