codeableconcept

If your diet is 90% potatoes and you do hard manual labor all day, you would absolutely need about 7 pounds of potatoes (2500 calories). I don’t think 13 pounds seems that crazy. I have sat down at a meal and eaten 3 pounds of potatoes before.

I think you’re probably right. It is an interesting thing to think about though — since carbohydrate to fat conversion is extremely inefficient, I think you could at least expect a more forgiving change in body composition during a period of over feeding.

This is similar in terms of macros to the traditional Irish diet in the 19th century, which for workers was purportedly made up of around 13 pounds of potatoes a day for an adult man. This traditional Korean diet appears to also be extremely high in carbs as a proportion. Of course these groups had significantly higher energy expenditures than most moderns, but it does seem possible that caloric excess in the absence of significant dietary fat does not drive obsesity / metabolic disease in the same way.