the 500 rule

cdpm said:

if the 500 rule for setting your bolus insulin to carb ratio
is based on the assumption that the average person consumes (thru food/drinks)
and produces(via the liver) 500 grams of carbs. daily

but a person eats say 100 grams of carbs
couldn't the 500 rule be changed?
to reflect the carbs you do eat?

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Every article I've ever seen gives the standard reference intake of carbs as 260g per day.

http://www.nhs.uk/Livewell/Goodfood/Pages/reference-intakes-RI-guideline-daily-amounts-GDA.aspx

Never heard of the 500 rule before. But yes I think you should match your insulin to your food intake according to your personal needs and the guidance of your medical advisors.

Hi. I've never heard of the 500 rule. Normally you adjust your Bolus to the amount of insulin you are having at a meal. It will vary from person to person. My DN in common with general advice started me at a ratio of 1 unit of Bolus to 10gm carb, but it needs to be varied from from person to person. If in doubt seek advice from the DN and start with a lower amount of insulin, using the meter a lot and finding the right ratio for you.

Hi. Probably worth adding that we all produce varying amounts of our own insulin and to avoid hypos it is important to use the meter to ensure we don't experience them from a Bolus and to start low at first. Has your DN given you any advice on carb-counting? Do discuss this with her.

The 500 rule leaves a lot to be desired and assumes that most people are eating approx 250g carb per day. Some are of course but many aren't. I always use trial and error and frequent bg testing to work out what my ideal insulin to carb ratio needs to be at different times of the day and adjust them to be in line with the action of the basal. Start with 1u to 10g and adjust the carb in the ratio to be whatever and test bg to see how the changes affect.... Try to keep to eating the same amount of basic carb for each meal and adjust the carb ratios to keep somewhere within the NICE guidelines or whatever a DSN or consultant has recommended. Once the ideal ratios have been sorted, the amounts of carb to be eaten can also be changed to allow for more food

Hi. It sounds like you were given typical bad NHS advice to have lots of carbs? This is great if you want to make your diabetes worse or put on weight if on insulin. Diabetics are by definition glucose intolerant. Would a coeliac have lots of gluten-based food; probaly not. Same for us with regard to carbs. We aren't allergic to carbs but the body can't metabolise them without enough insulin and we lack free insulin. This is why it's important when on the Basal/Bolus regime to match the rapid insulin shots to the amount of carbs in the meal.

I'm not sure, but most info I have read re the 500 rule refers to Type 1's, with Type 2 it is more difficult to judge as your level insulin resistance will also affect your insulin requirement. Your DN should be able to advise how to calculate your carb to insulin ratio, but I have found that it is a lot of trial and error until you find the right ratio to keep your BG under control.
More carbs = more insulin which also probably means increased weight as your body converts excess glucose to fat, unless you pursue an active lifestyle to burn the excess off.