Sherri Shafer, Registered Dietitian, Diabetes Management Part 1: Carbohydrate Counting
Hello, I’m Sherri Shafer.
I’m a registered dietician and a certified
diabetes educator here at UCSF.
My primary role for the last 25 years
has been as a diabetes educator
in the pediatric diabetes clinic,
the adult diabetes practice,
the diabetes teaching center, and
the diabetes and pregnancy program.
So I do diabetes across all age groups.
The first module is going to be
on carbohydrate counting which is
a key strategy in managing diabetes.
The objectives of this module are to
explain why carbohydrate counting is
a person with type 1 diabetes.
When using insulin to
name two pieces of information
needed to calculate the dose.
Explain the main limitation of
using sliding scale insulin for
a person with type 1 diabetes and
to list three available tools
available for counting carbohydrates.
Carbohydrate counting is one piece of
the puzzle in the complexity of managing
Not only does the person with diabetes
need to manage their insulin dose,
they need to consider what
their current blood sugar is.
They need to look at is
exercise planned or not, and
then they have to look at
the carbohydrate content of the meal.
Carbohydrate counting is a method to
assure type 1 diabetes Insulin doses
are matched to the food but it can also
be implemented in type 2 diabetes.
Many people with type 2 diabetes
use carbohydrate counting to manage
So introducing the carbohydrate foods,
whether you’re talking about grains,
fruits, starchy vegetables, legumes,
beverages with carbohydrate,
desserts with carbohydrate, they all
eventually digest into monosaccharides,
which enter the bloodstream.
Both the carbohydrate amount and
type of carbohydrate will
affect blood glucose levels.
Carb containing foods in the milk and
yogurt group are just that,
they’re not cheese, butter or cream,
because when you make cheese, it’s just
combining the protein and the fat, whereas
the milk and the yogurt have lactose.
Fruits and juices are quite
concentrated in simple sugars.
There’s grains, breads, cereals,
starchy vegetables like potatoes and
corn, the whole bean family.
All added sugars, honeys, sweets, and
syrups and the deserts made with them
are things that people with diabetes have
to consider when planning their dose.
The dose is based on three things,
the amount of carbohydrate and
the type that they’re about to eat, what
their current blood sugar level is, and
their level of physical activity.
When using insulin to carbohydrate ratios,
the person would be given,
with the help of an endocrinologist or
a doctor to figure out what their doses
should be, they would be given a ratio.
And that ratio would give you information
on how to cover the carbohydrate, but
also how to correct
an elevated blood glucose.
For example, a ratio of 1:15 means
one unit of rapid acting insulin for
every 15 grams of carbohydrate and
a unit for
every 50>100 as written here in blue means
they would take an extra unit for every
50 milligrams per deciliter, their blood
sugar was elevated above their target.
In this case, I chose 100 but
these can vary.
Somebody who is insulin sensitive,
such as a type 1,
typically needs about a unit per every
10 to 20 grams per carbohydrate.
Somebody with type 2 might use much more
because of their insulin resistance.
If we look at this ratio and a planned
meal of 90 grams of carbohydrates,
the person would take a unit for
every 15 or 6 units for the food.
The current blood glucose of 200 is
elevated above their target of 100 and
they would need two units
because it’s one unit for
every 50 milligrams per
decimeter over their target.
So the dose is comprised of two things and
this dose would add up to eight units.
Why not use sliding scale for type 1,
which was the gold standard for decades?
That’s all anybody used to do is give
a patient something like this table that
says if your blood sugar is between 70 and
100, take four units.
If your blood sugar is between 101 and
150, take five units, and so forth.
That has a built in increase as the blood
sugar levels rise above target but you’ll
notice that it doesn’t say anything about
the amount of carbohydrate being eaten.
Now a sliding scale dose such as this may
be more appropriate for somebody with type
2 diabetes who makes their own insulin and
they’re just very insulin resistant and
need a layer of additional insulin
to help lower blood sugar.
But this isn’t going to work very well for
a type 1.
If you look at these two meals,
the same does cannot possibly cover
every meal they eat at that time of day.
On the left you have an omelet cheese,
four sausages, a piece of wheat toast,
coffee and the total carbohydrate in that
meal is just 15 grams of carbohydrate.
Four units maybe way too much insulin for
The very next day, they might
eat a similar volume of food and
have a high carbohydrate meal.
In this case, a bagel that is
about 60 grams of carbohydrate,
a large banana 30 and
a glass of juice for 30.
They’ve had the same volume of food but
this meal adds up to 120
grams of carbohydrate, in this case,
four units maybe way to little.
So a sliding scale just doesn’t
nail it on every meal for
somebody who needs more accurate dosing.
The carb counting tools available to
people include the nutrition facts labels
on our packaged goods,
food composition carb counting lists,
there are carb counting books.
Some cook books will list the recipe and
give the portion size and
tell the amount of carbohydrate
calorie and so fourth.
Fast food restaurants and
chain restaurants have brochures.
They don’t always make them
available at the counter but
you can find that information online.
And there are many websites that can
be used for looking up information
on food composition as well as apps
that can be downloaded to your phone.
Looking first at the food labels,
when we’re thinking about carbohydrate
counting, we’re gonna zero
in on the serving size.
In this case, it says 1 cup and we’re
gonna look at the total carbohydrate.
In this case, it says 30 grams.
I’d say the most common mistakes people
make is up at the top, in parentheses,
it says 137 grams.
That actually is the weight
of the product and so often,
people see that as the carbohydrate.
That would be an inaccurate number.
The other common mistake is looking to the
far right column where you see in bold,
all lined up, the percent daily value and
this one says 10%.
Oftentimes, people with visual problems or
who don’t have good literacy skills
look at that number and are dosing for
that number and that’s incorrect.
I once had a grandmother give
insulin to the child for the weight.
For example, that would be 137 grams here,
when in fact,
the dose should have been 30.
And that was an urgent situation where
they had to feed the child juice and
monitor the blood sugar every half an hour
because of that overdose of insulin.
Frequently, people look at the sugars
instead of the carbohydrate but
we need to look at all of the
carbohydrate, not just the sugars and so
sugar and fiber are subsets
of the total carbohydrate.
Of the 30 grams here, two come from fiber,
three come from sugar, and
the remainder come from starch.
They just don’t need to
delineate that on the label.
And just as an information added,
the sugar’s here too.
It doesn’t tell you if it’s added white
sugar or if there’s milk or yogurt in it,
or if there’s fruit in it
because in chemistry any mono or
disaccharide would be listed under sugars.
I want to talk about the fiber for
a second because fiber doesn’t digest,
it is not broken down.
It pushes through our entire
intestinal tract, which is good for
the intestines because it stimulates them
and it also prevents constipation but
in terms of diabetes, it does not
contribute glucose to the blood.
So, some people should subtract the fiber
when they’re looking at a label and
here’s how you would decide.
Look at the total carbohydrate.
Here, it’s 13 grams, the fiber is one,
whether you’re taking a dose for
13 grams or 12 grams of carbohydrate.
It’s about the same dose, whereas
the other label, the carbohydrate is 10.
These are both tortillas, by the way.
The other carbohydrate total is 10 grams,
but the fiber’s 7.
If you subtract that, you’re left with
only 3 grams of carbohydrate from starch,
that are going to digest and
get into the bloodstream.
Now if you amplify that by having
somebody that eats three tortillas,
you can see that that dose
mistake could be costly.
So if somebody had three
of these tortillas and
counted it as 30 grams versus what
they really should count it as,
as 9, they would be overdosing on insulin.
Food lists, this is just an example
of what people work off of.
They have lists that have all
the milks grouped together,
all the starches grouped together,
all the fruits grouped together and
each portion size on the page has
about 15 grams of carbohydrate.
So in time, they learn to memorize the
foods that they eat day in and day out.
You can look down the list and see some
things are bigger like 3 cups of popcorn.
Some things are smaller,
such as a small apple, orange or
banana equaling 15 grams of carb.
I quote the word small because,
what do you consider small?
Many people just say every fruit
they eat is 15 grams of carb because
they’ve seen these lists but
in fact, that can’t be true.
A small apple off of these
lists is a 4 ounce apple and
so it’s important to look at measuring and
weighing things accurately.
Those measuring cups need to
be part of the household.
Food scales are the next level up and
so once somebody masters measuring and
using lists, we might move
forward with using a food scale.
As I said, apples have about
3.75 grams of carb per ounce.
This is an 11 ounce
apple, so 11 times 3.75,
41 grams of carbohydrate.
You do have access to other
lists that are peeled fruits.
I like to give them the ones with
the peeling on because then they can do
the whole fruit bowl on a weekend when
they have time and the whole thing’s done.
On an apple, you could write
on the sticker with a Sharpie.
If there’s no stickers on it, you can buy
them at the Dollar Store, 200 stickers and
just pop them on things.
Let’s look at this one, so
this is a very small apple, and
we’re going to say each ounce
has 3.75 grams of carb, and
this one actually,
I’m surprised this is a four ounce apple.
That is really 15 grams of carbohydrate,
you can see how small it is.
When we say a small fruit
is 15 grams of carb,
it’s about the size of a tennis ball
to maybe the size of a baseball.
If it starts looking like a softball or
that might be as much as double.
I wanted to mention,
things like asparagus, beets,
broccoli, cauliflower, carrots.
All of these have a little
bit of carbohydrate,
not as much as the other foods.
A half a cup cooked is about 5 grams
of carbohydrate but that can still
be significant for somebody who’s dosing
insulin exactly such as a type 1.
Another tool available would be
websites and I like Calorie King.
We’ll demonstrate that in a minute but
the USDA also has a complete list.
You can do food searches and you can
find out information about calories,
fat, carbohydrate, vitamins and so forth.
Some people like the myfitnesspal.com.
That also comes as an app,
as does Calorie King.
The chain restaurants
usually have the www name
of the restaurant dot com, and you can
access just about any restaurant that way.
When you get to their homepage,
you look for
some button that says nutrition facts or
You can press that button and
you can pull up an entire
menu that has all of that information for
you and print it.
We have people that carry the ones that
they eat at in their glove compartments
and they have them handy.
I wanted to demonstrate
the use of a website and
the good information
you can get off of one.
This is the one I like but there are many.
This is called CalorieKing,
it’s at www.calorieking.com,
it has a search for foods.
I’m going to do a couple of searches here.
Let’s start with a yam.
When you type in yam and
you do your search, you’re going to get
a whole list that you can scroll through.
I’m going to look for baked,
it’s right at the top, baked or boiled.
Click on that and now I have
an opportunity to add the serving size.
It’s defaulting to cups.
However, if I cooked a nice garnet yam,
I’d wanna put it on the plate,
I think it looks better than
shoving it in a measuring cup.
So I’m gonna use the drop down arrow and
set it on ounces.
Now I can use a food scale and just with
one quick step coming out of the oven,
I can put the yam on the food scale and
see how many ounces it is and
plug that in right here.
I’m gonna say we have a 5 ounce yam and
you can see that right as I put in the 5,
it said 164 calories.
It switches to a label,
I’m sorry I’m having trouble here,
that matches your food search, so for
a 5 ounce yam, you’ll see that it has
164 calories, for example, and
a total carbohydrate count of 39 grams.
Now below that, it shows you the fiber
is 5.5, which is pretty significant.
If I was taking an insulin injection for
this as a type I, I would subtract it.
I have the information, it’s easy
enough to do and get the correct dose.
One nice thing about these apps
is you can see the fiber content.
Let’s do another search.
Let’s do french fries.
We’re gonna search for french fries and
when you do that, you’re gonna get
a whole list that scrolls quite far down.
You’ll have all of the different fast
food restaurants, chain restaurants,
information will be compiled here.
But usually, at the top,
you’ll also have the average of you
cook them at home in the oven, or you fry
them, and you have those options as well
where you could weigh your french fries
at home, just as we did with the yam.
But, if I was at, I’ll pick the top one,
let’s say I was at McDonald’s,
I could click on french fries for
them and then
the scroll down gives me the different
sizes offered at that restaurant.
I can say, we’re going for
the large ones and
then we’d say, oh,
that’s 500 calories, forget that.
I’m going to go to the medium ones, 380
calories and then I can scroll down and
see that the carbohydrate is 48 grams for
the medium fries,
which usually surprises people.
When I have people with type 1
diabetes that find these websites,
you can just see them saying, oh my gosh,
I’ve been counting this as 30 grams all
this time and they start to recognize some
of the errors that they have been making.
In summary, this lecture introduced
you to the rational and tools used for
Alternatives to carb counting
are addressed in a separate lecture.
Some individuals are unable to count
carbohydrates because of literacy and
numeracy issues, and we do have
sample menus, many sample menus,
with set amount of carbohydrates that
we will produce for people like that.
Carbohydrate counting is
not always necessary for
somebody with type 2 who is
relatively easy to control.
They might need more basic
guidelines instead of something so
stringent as learning to count carbs.
Our patients with type 1, remember,
have diabetes their whole life.
We work slowly over time giving more and
more tips to add to their
level of knowledge because so
many times they have a good amount of
information that they’re working from and
they might being doing 80% of the work and
not getting the results that they want.
And that might be something that
a dietician or a diabetes educator can
help them with, is to figure out
what piece of the puzzle is missing,
how can they become more
accurate with carb counting.
So that their doses fit
their food better and
they have the blood sugar control
that they’re looking for.