• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Sensible degrees of accuracy

H

hanadr

Expert
Messages
8,157
Dislikes
soaps on telly and people talking about the characters as if they were real.
those of us who are numerate and possessed of a calculator, abacus,slide-rule or knowledge of logarithms or multiplication tables, can make calculations to pretty much infinite degrees of accuracy and many deccimal places. It's not however a sensible thing to do with calculating the carbs in food.
The reasons are: the composition of any food varies from portion to portion.
We can weigh foods with very limited accuracy [Most kitchen scales are no more accurate than the nearest 2 grams, if that]
Thus working to an estimate of the nearest 2 grams of carb is probably as accurate as we can realistically be. Decimal fractions of grams of carb are unlikely to be accurate , thus are pointless. Rounding up or down to the nearest whole number will be good enough for anyone's purpose.
Hana
 
That's part of the reason I aim for <20g. The usually accepted upper limit for deep ketosis is 30-50g. If I make a mistake with my measurements, then I still have a big margin of error before I accidently knock myself out of ketosis.
 
fergie
Is it an abacus or a slide-rule you are using?
Hana
 
hanadr said:
fergie
Is it an abacus or a slide-rule you are using?
Hana
Click to expand...

Nah Hanadr, like you said, I only really eat spinach and salad and avacados. I used to track everything religiously in cron-o-meter (12g of shredded carrot in a Tesco salad), but in the end I realised that I never went about 10g a day, so I stopped measuring and started guesstimating.

I'm a recovering Engineer, but I'm not quite old enough to have used a slide rule...
 
fergie
my Dad was an engineer and he taught me how to use a slide rule.
I taught Sciences, but one day, a kid came and asked me how to use a slide rule. I directed him to the maths department.
"No-one there knows how to use one Miss!They sent me to you!" He said
i never found out if they thought I could use one, or I was just the oldest member of staff :lol:
i did teach the kid simple multiplication.
Hana
 
I'd settle for the nearest 2g :thumbup:
 
Noblehead
I'd settle for the nearest g too,
but I suspect we rarely get that close. There are too many variables.
Hana
 
hanadr said:
Noblehead
I'd settle for the nearest g too,
but I suspect we rarely get that close. There are too many variables.
Hana
Click to expand...


I'll not argue with that Hana :)
 
Srephen
Do you mean that you didn't have to use log tables in your maths exams? I think it was cheating allowing the use of calculators :lol:
Hana
I agree about accuracy, but I do think for those of us that use insulin and possibly more starchy carbs than you that it's important to weigh starches at the beginning and every now and then to check your estimation later. I guestimate non starchy .
I continue to weigh my oatmeal, the bread and potatoes I eat at home. I'm sure it helps .
 
borofergie said:
hanadr said:
fergie
Is it an abacus or a slide-rule you are using?
Hana
Click to expand...


I'm a recovering Engineer, but I'm not quite old enough to have used a slide rule...
Click to expand...
Well I oo was lucky enough to learn how to use a slide rule and as time went on I began to feel a bit dated . Then One day I went to sit a university exam and the rubric said that it was forbidden to use a n electronic calculator so i sat the exam using my trusty slide-rule - gave the lecturers a laugh 'cos they couldnt fault my sticking to the rubric :lol:
 
Still got my slide rule, and calculators WERE outlawed. Also used log tables, learned calculus, and used norries tables for astro nav and spherical trigonometry. Still got them too.
 
I'm like Stephen, on a very low carb diet, but I do weigh. I weigh absolutely everything. It's for my own peace of mind more than anything else. While today I only had 9g of carbs, I also do realise nothing is going to be perfect, so also have to have a margin of error. I am also in deep ketosis, and would hate to come out of it. There is no way I want to go through 'Atkins flu' again, once was more than enough. :lol:

It may be unnecessary, but for me, the peace of mind is worth the odd gram either way, as I make sure I have that leeway.


What the heck is a slide rule?
 
"Decimal fractions of grams ... are pointless."
Click to expand...
Surely you don't mean that.

What is a "calculator"? Someone who calculates? Slide rules were a luxury a few of the class could afford. I've still got my Otis King cylindrical slide rule. And I can still differentiate from first principles.
 
Defren said:
What the heck is a slide rule?
Click to expand...

Never, EVER, ask an engineer to show you his slide rule... :shock:

1976_slide_rule.jpg
 
IanD said:
"Decimal fractions of grams ... are pointless."
Click to expand...
Surely you don't mean that.

What is a "calculator"? Someone who calculates? Slide rules were a luxury a few of the class could afford. I've still got my Otis King cylindrical slide rule. And I can still differentiate from first principles.
Click to expand...

rfwD.jpeg
 
Back
Top