I was searching in books and came across this info: many studies shows that eating leguminous (?) regularly help lower cholesterol levels.
They don't say anything about swallowing whole peas but it seems to explain why it works
FIL took a blood test a month and an half after beginning to eat the peas and his cholesterol levels had drop within the normal range... The doctor don't really beleive the peas are the factor but he didn't say anything against it either.
If anyone have more infos, they are welcome I will search for more too.