That's a very old saying, from the time when there was no fridge. Nowadays it's not a concern anymore. BTW, nutrition is a vague word.
-sailor(Ocean & Mountain);
2017-9-23(#11066932@0)+2
你全包了可解。没剩的,娃们就 save 了。
-troyd(素食兽);
2017-9-23(#11066898@0)+8
I doubt "剩菜含高浓度亚硝酸盐". Human bodies need sodium nitrite. Only preserved food, like sausage, has high amount of sodium nitrite.
-sailor(Ocean & Mountain);
2017-9-23(#11066969@0)+4