Just wanted to know are carbs or calories the reason why people gain weight? Cause some people are saying carbs and others say calories.
It's not quite as simple as an "either/or" situation.
Excess calories (more calories eaten than burned) will be stored as fat. This is a general rule that applies to all diets. It is a common adaptation of animals, since most animals will naturally experience periods of low food availability and will need their fat stores to keep them going during such times.
Now for some people, too many carbs OR certain kinds of carbs called high glycemic carbs
will trigger a biochemical response that promotes the rapid conversion of consumed food into fats.
So, to answer your question, both calories and carbs can cause people to gain weight. Any individual who wants to lose weight should first make sure if just one or both of these possible reasons apply.