Yes i highly doubt the validity of his statement. My calorie intake is around 2500 a day to maintain a weight of around 70kg (with some excerise). If i wanted to gain 2kg of weight id have to consume around 10000 excess calories over a period of two weeks.

I have also many times lost 2kg over a period of a few weeks by simply being lazy to calculate my calorie intake while excersising more than usual. Gaining weight takes ridiculously more effort for me than losing weight.

> If i wanted to gain 2kg of weight id have to consume around 10000 excess calories over a period of two weeks.

Which is of course trivial to do. That's one kebab extra per day.

You just don't eat caloricilly dense food at a high frequency and grossly underestimate how many calories someone can eat in a day [1]. Also, for most people losing 1kg a week is considered very fast weight loss at the border of what's recommended for safe caloric restriction.

1. https://news.ycombinator.com/item?id=36339530

I've lost about 65 lbs, then gained about half of that back. If I overeat in a single day, I can put on a pound or 2. If I don't compensate the next day for that excess, some of that weight will stay on. If I don't compensate within a couple days, all of that weight will stay.

I've had this struggle for a few years, gaining about 30 lbs over the course of a few years.

What the GP said might not apply to everyone, but it does apply to those who have eaten to excess in the past and are now struggling to keep that excess weight off again.