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Serving sizes and weight

tyediri
tyediri Posts: 183 Member
edited November 2024 in Health and Weight Loss
So I've been reading a few threads where the OPs have been scanning the packets and logging serving sizes. Now I do this sometimes myself, but mostly weigh and am losing at a snail pace which I am comfortable with as I have very little to lose.

But I was just wondering what some of the differences between serving sizes and actual sizes that you have seen?

For example I weighed a slice of bread last week that was meant to be 36g a slice, but was actually 45g.

But today I found that 2 slices of bread that was meant to be 78g was exactly 78g! I was way too excited about this than I should have been! :-D

Replies

  • deannalfisher
    deannalfisher Posts: 5,600 Member
    by law - they are allowed to have up to 20% variation - i believe
  • tyediri
    tyediri Posts: 183 Member
    Yes I've heard that. Is it + or - 20%, because I don't recall many servings that were more than a couple grams less than stated on the packet. They always seem to be more? (apart from my 2 perfect slices of bread today!
  • Seffell
    Seffell Posts: 2,246 Member
    I very rarely weigh prepacked food because everytime I weigh it it is either the same as on the package or the error is several calories so it doesn't matter. That said, I eat mostly food packaged by a particular supermarket so it might be that they are quite accurate.
  • PAV8888
    PAV8888 Posts: 14,664 Member
    my favourite protein bars are supposed to weight 60g. They have ranged from 52g to 70g. Most of the time they are between 61g and 65g.
  • Francl27
    Francl27 Posts: 26,368 Member
    The 20% has nothing to do with the serving size, it's about actual calories per serving. So it can be 20% off on top of that.
  • claritea1
    claritea1 Posts: 23 Member
    I would go crazy if I weighed every last thing, like a slice of bread. Things like that I scan and log and move on. Now, I do weigh most foods, but not typically not those that are prepackaged or foods like a bagel or slice of bread.
  • tyediri
    tyediri Posts: 183 Member
    Francl27 wrote: »
    The 20% has nothing to do with the serving size, it's about actual calories per serving. So it can be 20% off on top of that.

    I had no idea! I thought it was related to serving size.
    I guess it does make sense, especially for premade meals and the like. I can't imagine the calorie content can vary too much for 100g of bread, milk or cheese?
  • tyediri
    tyediri Posts: 183 Member
    claritea1 wrote: »
    I would go crazy if I weighed every last thing, like a slice of bread. Things like that I scan and log and move on. Now, I do weigh most foods, but not typically not those that are prepackaged or foods like a bagel or slice of bread.

    I never used to either, but thought I'd give it a try as I only have 10lbs to lose and have to tighten up my logging.
    Now I'll weigh a couple slices of bread from a loaf to get an idea of what the actual weight is like, and then don't weigh the rest of the loaf. Working ok so far. I'm losing about a pound every 3 weeks!
  • DX2JX2
    DX2JX2 Posts: 1,921 Member
    tyediri wrote: »
    Francl27 wrote: »
    The 20% has nothing to do with the serving size, it's about actual calories per serving. So it can be 20% off on top of that.

    I had no idea! I thought it was related to serving size.
    I guess it does make sense, especially for premade meals and the like. I can't imagine the calorie content can vary too much for 100g of bread, milk or cheese?

    Milk won't be a big deal as 100g of whole only has something like 50-60 calories? A 20% difference would put you at 10-12 calories. Assuming bread and cheese at ~100 calories per ounce would be a bigger deal. That 20% difference for 100g would put you at ~60 calories or thereabouts.

    That said, it's still not a huge amount of calories and since the 20% difference can run in both directions it's not something that you generally have to worry about.

    It's important to remember that the 20% variation is for calories contained within a given quantity/weight of product and has nothing to do with serving sizes or servings per container.
  • tyediri
    tyediri Posts: 183 Member
    DX2JX2 wrote: »
    tyediri wrote: »
    Francl27 wrote: »
    The 20% has nothing to do with the serving size, it's about actual calories per serving. So it can be 20% off on top of that.

    I had no idea! I thought it was related to serving size.
    I guess it does make sense, especially for premade meals and the like. I can't imagine the calorie content can vary too much for 100g of bread, milk or cheese?

    Milk won't be a big deal as 100g of whole only has something like 50-60 calories? A 20% difference would put you at 10-12 calories. Assuming bread and cheese at ~100 calories per ounce would be a bigger deal. That 20% difference for 100g would put you at ~60 calories or thereabouts.

    That said, it's still not a huge amount of calories and since the 20% difference can run in both directions it's not something that you generally have to worry about.

    It's important to remember that the 20% variation is for calories contained within a given quantity/weight of product and has nothing to do with serving sizes or servings per container.

    That is good to know ! I always thought it was related to serving size!
    You can always learn something new on here. :-)
  • PAV8888
    PAV8888 Posts: 14,664 Member
    I don't weigh prepackaged single portions. I figure any error there is made up for with me doing things like weighing a banana the night before with the peel, packing it for lunch, and then peeling it and not weighing the peel later.

    This is a criminal banana hit! A quick approximation is 32% of your banana is peal!
This discussion has been closed.