More than one research studies show limited evidence of slimming effect

https://www.webmd.com/diet/features/truth-about-chia#1

However, I feel chia seed is very filling yet tastes very different from any of the fatty or starchy foods in my life. Unlike nuts, chia is not addictive. I would never eat more than 3 spoonful of chia seeds a day. This is the main reason for my belief in its slimming benefit.

The other reason is that chia expands inside, making me feel fuller longer.

— carbs

Almost all the carbs in chia seeds are fiber. Chia doesn’t feel starchy at all.

Q: Is the fiber contributing to calorie intake?
A: I feel answer is … research-needed

— fat:

Research show a non-trivial amount of fat content, but I don’t feel any fat in its texture.