It surely is not excess calories – that’s just a description of how people gain weight. It does not explain why, so it’s not helpful.
To be able to lose weight it’s hugely helpful to understand what really caused it, so that the cause can be removed.
Here’s another great presentation by the fantastic Dr. Jason Fung, from the recent Low Carb Vail conference.
The presentation – including captions – is now available on the member site.