One interesting item to note, sometimes the "use by" date is because after that time the packaging may start to break down and contaiminate the product. That is why plastic water bottles have a date on them - as the water sure is not going to go bad.

Some canned goods as a chemical liner on the inside, and sometimes that is made from stuff that isn't good to ingest. Does not make you sick like spoiled food will, but can cause long term bad effects.

That's funny, Watson! There are some things I give a pass to, but I will not mess around with anything that was not commercially made, therefore has some preservative (i.e. home made/locally made bottled goods like sauces, jams, etc.) Dairy is another that I just *can't* deal with if it smells a bit off. I'd rather be safe than sorry, and I've had food poisoning more than once in my life. Not worth it to me!
With spices, I'm a little fussy because I really enjoy cooking - I try to be sure they are fresh, and I have a local Penzy's so really, there's no excuse!

I grew up in a household - and married into a family - where wasting food was almost a cardinal sin -

We threw away the top two or three inches of the sauerkraut in the crock that had turned really brown, but ate the rest of it. (I was born in 1941)

My in-laws made "cottage cheese" by using curdled milk and then straining the whey out of it. They did this in the breezeway. I never ate any of that. Actually, they were poor, and when they butchered a pig, I think they used almost everything but the squeal.

I don't remember any of us having many stomach upsets back then.

I considered white toasted Wonder Bread to be a delicacy - Mom either baked or bread was purchased at the bakery.

Mom quit baking when her husband stuck a loaf of her bread in the oven to get it "doner". Mom was an excellent cook - her husband had some weird eating habits!

Hmmm. I have made ricotta cheese with fresh milk. Quite tasty and easy.

I definitely use common sense but do use dates as a guideline. It is common sense that nutrients do go as time goes by

There are two articles on this link, one about medicines and one about food expiration dates. You may find some surprises.

https://www.theorganicprepper.com/?s...ins+medication

when I did flylady in 2000-2001 I found stuff in my cupboard seven years past the pull by date.
Yesterday I was getting out the penne pasta and found a package of Bob's Red Mill cracked freekeh, one of their ancient grains offering, it was in wide use about 4000 years ago.

I have no idea what my plan was, why I bought it. This is how the cupboard oldtimers get started...
On the other hand I leave my marshmallows and Peeps open because they need to be ripened to be edible, chewy like taffy, the older the better!

Re marshmallows - they will turn into soft rocks if they are around long enough.

You're home ec teacher was right to say that, although it has nothing to do with food safety. However, baking powder does loose its raising power over time, so using old baking powder won't get you an upset tummy or such, but can result in a flat cake... BTW: If baking powder changed its colour slightly and has a pink shine, it's definitely too old and should be replaced!

Most dry ingredients and especially spices, won't turn "dangerous" to your health when expired. However, they may loose their flavour over time. My general rule of thumb with anything is: If it looks ok, smells ok and when I try tastes ok, there should not be any problem with it!

Canned goods literally keep forever (despite the expiry date). The only time when one should absolutely NOT eat canned goods (regardless of the expiry date) is when the can is bulging or swollen - that's botulism and can be deadly!