Chestnut and sweet potato are mainly starch, while chestnut contains a lot of protein. Sweet potatoes must be sweeter than chestnuts, right? Starch is decomposed into glycogen in the human body to provide heat, but too much glycogen will accumulate in the body and eventually be converted into fat for storage in various ways!

I suggest you eat chestnut, where we produce chestnut! We eat so many chestnuts every year. Why can't people get fat? Ha ha!