So, type 1 diabetes is a condition where the body can no longer produce insulin. Insulin
is a hormone that controls the level of glucose within the blood. And it's really important
that that level stays within a normal range as much of the time as possible. Because if
not, then over time that can lead to some of the complications associated with having
diabetes. Now, in type 1 diabetes, the body cannot produce insulin so it has to be given
by injection. However, the amount of insulin you give will depend on the food that you
eat. And so, it really isn't the case that you can just eat whatever you like if you
have type I diabetes regardless of knowing what it is, because while in theory you can
eat all sorts of different things, what's really important is you need to know how much
carbohydrate is in each meal that you're eating. Because that will determine how much insulin
you need to inject. And that's really important because if you inject too much insulin, there's
a risk that your blood glucose level will go too low. And anyone with type 1 diabetes
will know that a low blood glucose or a hypo is really quite unpleasant. On the other hand,
if you don't inject enough insulin, then your blood glucose level will go too high. And
as a result of what you've eaten not being covered by the insulin injected. So, first
and foremost it's really important you know how many carbohydrates are in what you're
eating. And that means that each person with type 1 diabetes needs to understand, needs
to learn how to assess the carbohydrates in each meal. In each and every meal. Because
every single meal will have an effect. Now, some people will choose to have some meals
without any carbohydrates. And that's fine. But of course, in order to do that you need
to know the foods that don't have carbohydrates and that all in is encompassed in what we
call the dietary management of type 1 diabetes.
So if you have type 1 diabetes I really do
think that restricting your carbohydrate intake is a very good idea. The reason for saying
that is that it's the carbohydrates in the food that make the blood glucose level go
up. And that's what we want to avoid. Now of course you treat that-- you treat type
1 diabetes with insulin and you take insulin with each meal to cover the carbohydrates.
And in fact, there was a vogue some years ago to say that if you've got type 1 diabetes
with the modern insulin that we have available now, you can pretty much eat what you like
as long as you give the right amount of insulin. Now, over the years since then I've really
come to believe that that just doesn't seem to make sense. And why is that? Well, firstly
if you're having a meal with a large amount of carbohydrates, you have to inject a large
amount of insulin. That's obvious. That isn't necessarily such a good idea. If you have
too much in your insulin in your system then there is of course a greater risk of having
a hypo which someone with type 1 diabetes we'll know can be a very unpleasant experience
to say the least. Secondly, a meal which has a large amount of carbohydrates can raise
the blood glucose level for sometimes many hours. And that may not correlate with the
the length of time that the insulin is acting particularly the shorter acting insulins that
we tend to use nowadays. And again, if there's a large amount of insulin in the system, there
is an increased risk of the insulin working at a time when the carbohydrate is-- there's
a mismatch if you like.
So type 1 diabetes requires treatment with
insulin and there are lots of different insulins available. Nowadays, I really feel that someone
with type I diabetes should be treated with what is called a basal-bolus regimen. That
means having two different types of insulin. The first is a basal insulin there's some
long-acting insulin which is usually given once or twice a day depending on the type
of insulin and how long it lasts. And there are a number now that are available on the
market. The ones that we tend to favour are those that are called long-acting analogues.
That means that actually they've been, if you like, modified so that their effect on
the glucose level is sustained and is stable over a long period of time. And that has huge
benefits compared with the older longer-acting insulin where from one injection to the next
you really couldn't predict whether the peak effect would happen two hours after injection
or four hours after the injection. And then the bolus element of the basal-bolus regimen
is the boluses of insulin that are given with meals. And usually now we use what are called
fast-acting analogues that have, again, have been modified so that they can be absorbed
really quickly from when they're injected so that they can begin to work as you're eating
your meal. And again, there are a number of those that are available now. To be honest,
I don't think there are significant differences between them and any one of the newer fast-acting
analogues should work well for most people. Now, one thing that I do recommend is that
in injecting your mealtime insulin it's so important to inject before you eat. There
was a vogue a few years ago when these incidents came out to say that actually they work so
quickly you can even eat and then inject afterwards. The problem there is that sometimes people
would just forget to inject, but more commonly by the time you finish your meal your blood
glucose level could always already be really quite high. And so rather than always having
to play catch-up, it does make sense to inject before you eat.
Insulin pump therapy is something that can be really helpful to a number of people with
type 1 diabetes. So essentially what this means is that instead of injecting insulin
through the skin several times a day, the user of an insulin pump has a pump which is
connected to a little cannula that sits beneath the skin and delivers, pumps a very low flow
rate of insulin continuously throughout the day and throughout the night. Now, the great
advantage of insulin pump therapy is that the amount of insulin that is infused can
be varied automatically; can be pre-programmed to deliver more insulin during certain hours
of the day and less at other times of day. This is particularly useful for people who
find that they are a risk of having hypos or their blood glucose level going low overnight.
It's also useful people for people whose activity levels vary quite a lot. And the great thing
about an insulin pump is unlike an injection where once you've injected it's working and
you can't take it out again, with a pump you can switch it off. And so, if you find that
your blood glucose levels going too low or suddenly you're having to be more active which
risks it going to low, you can simply suspend the infusion which means that it will allow
your blood glucose level to rise without having a hypo and without having to take extra carbohydrate,
for example to keep the level up. Now some people are under the impression that if you
have an insulin pump it does all the work for you. Well, we're not quite there yet.
You still need to monitor your blood glucose and you still need to give the boluses of
insulin before each meal. Now the insulin is in the pump so you don't need to inject
but what you do need to do is calculate the dose you need for each meal based on the carbohydrate
intake and then tell the pump by means of burning up and pressing a few buttons to give
just that amount of insulin for you. In many people it can be transformational using an
insulin pump and it's something that I recommend for a number of people where using injections
just doesn't quite lead to the level of control that they aspire to.