Managing Type 1 Diabetes

The aims of diabetes management are threefold:

  • To achieve good blood glucose control
  • To minimise the risk of developing long-term complications
  • To enable you to lead a normal well-adjusted life

If you have Type 1 diabetes then your diabetes management will hinge on your insulin injections or insulin pump settings, your blood glucose monitoring, and how you fit them to your daily life. You will find that it is a bit of a juggling act, getting everything just right. Don’t worry if it doesn’t all come together immediately; there are a lot of things to learn about before you can apply the principles of diabetes management to your own life.

This section deals with the principles of managing Type 1 diabetes and looks at the effects of insulin, food, exercise and illness on blood glucose levels. You should also take a look at the section on “Control”.

What’s covered on this page

The basic principles of managing Type 1 diabetes

Diet – Food Choices



Sick Days



The basic principles of managing Type 1 diabetes

Your ultimate aim is to keep blood glucose levels close to the normal range in order to feel good from day to day and to give you the best possible odds in the fight against long-term complications.

You will need to learn what makes the blood glucose level rise and fall and how you can minimise the swings in your own blood glucose level.

Food, stress and illness all raise the blood glucose level. Insulin and exercise lower the blood glucose level. Normally your pancreas would produce just the right amount of insulin at just the right time to cope with the fluctuations in blood glucose level that all of these factors cause. Good diabetes management involves continually juggling these factors and assessing what’s going on by regular finger-prick blood glucose testing. In order to keep on top of your diabetes, you will frequently need to try to second-guess what’s going to happen.

Insulin needs to be injected. It provides you with a background level of insulin needed to keep the body ticking over and it deals with the glucose that is absorbed into the blood after meals. There are a number of different types of insulin and you will probably be prescribed a combination of insulins, to be injected at different times during the day. This forms your insulin regimen. Having the right insulin regimen to fit your lifestyle is one of the most crucial aspects of diabetes management.

Depending on your insulin regimen, you may need to eat regularly, at set times throughout the day. Your diet should be healthy and nutritious. You will need to consider how much you eat and when you eat it. You will also need to look at the types of foods that you eat and assess the effects that they will have on your blood glucose level.

You will hear time and time again that exercise is good for diabetes and that it will help you to control your blood glucose levels. In fact, this is really only true for people with Type 2 diabetes. Although exercise has many benefits for all people – with or without diabetes – it can complicate blood glucose control in Type 1 diabetes unless it is properly handled. You will need to learn how to incorporate exercise into your daily life whilst keeping good control.

Illness plays havoc with the workings of most of our body systems, so it is not surprising that diabetes control is affected during periods of illness. It is very important that blood glucose levels don’t become dangerously high if you are ill or have an infection of some sort. So, in order to prevent diabetic emergencies it is wise to follow sick day management guidelines.

What things need to be considered?

Important factors will include:

  • Types of insulins used
  • Timing of injections
  • Choice of injection site and other factors affecting the absorption of insulin
  • How your insulin regimen is matched to your body’s natural insulin needs
  • How insulin is matched to food intake
  • Making appropriate adjustments (e.g. to insulin dosage) to cater for changes in the daily routine (e.g. exercising)
  • Using blood glucose monitoring results effectively

In addition to the above, the successful management of your diabetes will also depend on:

    • Your access to adequate information, education and support (Learn More About Diabetes – INDEX is a good place to start)


  • A good working relationship with your diabetes healthcare team
  • Regular check-ups to monitor your progress (“Get Checked”)


Setting Targets

An important element of diabetes management is setting targets or goals for yourself. This can be especially useful in the early days or if you feel that you’re not in control of things.

First, you will need to identify your goals, and then prioritise them. If you have just been diagnosed, then your goals will be different from someone who has had diabetes for some time, but has decided to take steps to improve their control.

Make sure that your goals are realistic. Remember, Rome wasn’t built in a day!

For more guidance on setting and achieving goals, see “Setting Goals and Making Changes”.

Diet – Food Choices

All people with diabetes are advised to eat a healthy, balanced diet. This is a way of eating that is recommended for everyone.

However, people with Type 1 diabetes need to do more than just eat ‘healthily’. The quantity, type and timing of your food choices are just as important as making sure that you have had your daily quota of fruit and veg.

You can learn more about eating a balanced diet from the pages on “Healthy Eating”.

Here, we focus on the effects of food on blood glucose levels and the relationships between insulin, diet and blood glucose levels in the management of Type 1 diabetes.

Carbohydrates, blood glucose and insulin

Carbohydrate foods have the greatest effect on blood glucose levels and it is the starchy foods – bread, cereals, potatoes, pasta, rice etc. – that you will need to pay most attention to you.

Carbohydrate foods are mostly broken down into glucose by digestive enzymes. The glucose is then absorbed from the intestine into the bloodstream (usually 1 – 2 hours after eating) and this causes the blood glucose level to rise. Insulin is needed so that the body’s cells can take this glucose from the bloodstream and either use it for energy or store it for later. People who do not have diabetes will produce just the right amount of insulin to cope with the rise in blood glucose that occurs after a meal. Insulin on demand allows the person without diabetes to keep blood glucose levels within the normal range, even after a meal rich in carbohydrates.

Getting the balance right

If you have Type 1 diabetes then your body no longer produces insulin; you have to inject it yourself. In order to keep the blood glucose level close to normal after eating, you need to inject just the right amount of insulin to deal with the food that you eat. It is also important that the injection is timed right, so that the insulin is arriving in the bloodstream at the same time that the glucose from the digested food is being absorbed from the gut.

If there is too little insulin (for the amount of glucose coming from the digested food) then the blood glucose level will rise too high (hyperglycaemia). If there is too much insulin (or not enough glucose coming from the digested food) then the blood glucose level will fall too low (hypoglycaemia).

So, your food intake needs to be closely matched by your insulin injections. This is why you will need to consider not only what you eat, but how much you eat, and when.


Different food types

The overall effect of a meal on the blood glucose level will depend on the different types of foods making up the meal.

Glycaemic Index

Different types of carbohydrate foods are digested at different rates and therefore have different effects in terms of raising the blood glucose level after a meal. Some foods are quite rapidly digested to glucose (e.g. cornflakes), whilst others take longer for the glucose to hit the bloodstream (e.g. All-BranTM). The effect of different carbohydrate foods on blood glucose levels has been quantified by the Glycaemic Index (GI). Foods with a low GI cause less of a spike in post-meal blood glucose than those with a high GI.

You can learn more about the GI in “Food Choices“.


It is still widely believed amongst the general population that people with diabetes should avoid eating sugar because it causes a rapid increase in blood glucose levels. This is not true! Table sugar, which we sprinkle on our cornflakes, actually causes less of a spike in blood glucose than the cornflakes themselves. Sucrose*, surprisingly, has a lower GI than cornflakes.

As part of healthy eating, we are all advised to cut down on sugar – this is because it has little nutritional value, it does little to satisfy the appetite and it’s a source of ’empty calories’.



Table sugar is not the same as glucose. Table sugar is called sucrose and is a disaccharide – it contains two sugar molecules: one fructose and one glucose. Table sugar needs to be broken down by digestive enzymes before the fructose and glucose can be absorbed. Glucose is absorbed quickly because it does not need to be broken down (digested) first.

Protein and Fat

Carbohydrate foods have the greatest effects on blood glucose levels because they are mostly digested to glucose, which is absorbed from the intestine straight into the bloodstream. However, proteins and fats in the diet affect blood glucose levels too.

Excess protein in the diet that is not needed by the body is converted to glucose by the liver. This means that consuming large amounts of protein can result in an increase in blood glucose levels several hours after eating.

The most significant effect of fat is probably to slow down the rise in blood glucose after a meal. Fat delays the rate at which the stomach empties – this has the knock-on effect of slowing down the absorption of glucose from digested carbohydrate foods. You might think that this is a good thing, but remember that a high-fat diet is not necessarily a healthy diet.

Which types of foods contain protein, fat and carbohydrate? See “Healthy Eating” and “Food Choices

Putting the theory into practise

Remember, your aim is to keep blood glucose levels close to normal. Eating causes the blood glucose level to rise; the aim of your insulin injections is to minimise ‘post-meal spikes’ in blood glucose without causing hypoglycaemia (low blood glucose).

In order to understand the relationship between the food that you eat, your blood glucose levels and the insulin that you inject you will need to learn about the different types of insulin that make up your insulin regimen. You should know when the insulins act, and which parts of your insulin regimen aim to cover which meals.

Should my meals be tailored to my prescribed insulin regimen?

In years gone by, people with Type 1 diabetes were advised to stick to quite a rigid meal schedule, which was determined by their insulin injections. Some insulin regimens still call for this to a certain extent. However, these days it is generally recognised that it is better to derive an insulin regimen that suits the individual person’s lifestyle.

So, in most cases insulin should be tailored to your food intake and not the other way round. This assumes that you are eating a healthy and nutritious diet that fulfills your needs.

To start with then, you will need to find the right insulin doses for an ‘average’ day in your life. In practical terms, you will need to eat a normal healthy diet, trying to eat roughly the same at the same time each day. Using blood glucose monitoring to guide you, the timing and/or dose of your insulin injections can be adjusted. Your healthcare team will help direct you in this. Your aim is to establish a routine, which gives reasonable control of your blood glucose levels, and fits in with your lifestyle. Then you can work from this baseline, fine-tuning your control and perhaps also introducing more flexibility.


An important role of diet in managing Type 1 diabetes is preventing low blood glucose levels (hypoglycaemia).

Some insulin regimens require you to have snacks in between meals in order to prevent hypoglycaemia. Snacks are not always necessary though, so check with your doctor and/or dietitian to see if you need to snack between meals.

A bedtime snack is, however, essential for all people with Type 1 diabetes. This ensures that blood glucose levels don’t fall too low during the night.

Snacks are also very important before exercising, especially if the activity does not form part of your regular daily routine. This is to prevent exercise-induced hypoglycaemia.

Accommodating change

In practise, most people have a regular insulin regimen, which is tailored to their ‘average’ day. The insulin dose and timing of the injections relates to how much is usually eaten and when. In theory, you will know that your insulin dose is just right for your ‘normal’ eating pattern. Any changes you might make to your usual day may need to be catered for by an appropriate tweaking of the insulin dose. Your diabetes team will be able to give you personal advice on how to make adjustments to cope with changes to your normal schedule.

As a general rule, more food (especially carbohydrates) needs more insulin, otherwise the blood glucose level will rise too high. Less food (especially carbohydrates) needs less insulin, otherwise the blood glucose level will fall too low. It is important to get the adjustment just right – or you may find that you have overcompensated for the change and given too much or too little insulin.

Use blood glucose monitoring to find out whether your adjustments are working; make a note in your diary of the changes you made and learn from experience. The most informative times to test are before eating and then 1 – 2 hours after your meal.

Delayed or missed meals are probably the most common cause of hypoglycaemia. Take steps to avoid low blood glucose levels if you know that you are not going to be able to eat your usual meal. Have an extra snack to keep you going and keep an eye on your blood glucose level.


Fine tuning your diet

Use your blood glucose test results and your knowledge of the effects of food on YOUR blood glucose levels to fine tune your diet for better control.

Here is a summary of some of the main points for your consideration:

    • Eat a healthy and nutritious diet
    • Aim to eat relatively consistent amounts from day to day
    • Use food labels
    • Use the Glycaemic Index
    • Consider the potential effects of fat and protein in your diet
    • Use blood glucose monitoring to assess the effects of different food types on your post-meal (2 hr) blood glucose levels (e.g. compare wholewheat varieties of bread, rice and pasta with their white counterparts)
    • Know when your insulins act and consider the time that you eat with respect to the time that you inject your insulin
    • Use a calorie counter, or similar book, to assess the carbohydrate, fat and protein content of foods




There is no doubt that exercise is good for everyone. You may read that exercise helps to control blood glucose levels – this is very true, but mainly for people with Type 2 diabetes. For those people with Type 1 diabetes, exercise can cause some problems if it is not dealt with properly.

Learn how to incorporate exercise into your daily diabetes management, then you can reap the benefits of an active life without compromising your blood glucose control.

Important note:

Always check with your doctor or diabetes team before starting any exercise programme. There may be reason for you to take special precautions or avoid some forms of exercise.

More general information on exercising safely and tips for increasing your level of activity can be found in “Physical Activity“.

Here, we look at the ways in which exercise or sports can be fitted into your diabetes management, with the right adjustments in diet and/or insulin.

The relationship between exercise, blood glucose and insulin

Firstly, we need to consider what normally happens in people who do not have diabetes. This will help you to understand why adjustments need to be made to your treatment plan when you exercise.

Exercising muscles need fuel for energy and this is supplied by glucose and fatty acids. It is the level of insulin in the blood that controls the availability of both of these fuels.

Glucose is normally stored in the form of glycogen in muscles and in the liver. When exercising, the glucose stored locally in the muscles is used up first. Then the muscles take glucose from the bloodstream. This lowers the blood glucose level. The falling blood glucose level acts as a signal to the beta cells to reduce their insulin production. This lowers the level of insulin in the blood. Glucose is then released from the liver to top up the blood glucose level in order to keep it within the normal range.

The critical point in this series of events is the decline in insulin production, which occurs in response to the exercise and drop in blood glucose. Low insulin levels encourage the liver to release glucose into the bloodstream. Low insulin levels also favour the breakdown of fats into fatty acids, providing the other source of fuel for exercising muscles.

Note: insulin secretion is reduced, but not stopped altogether. Sufficient insulin is produced so that cells can access the glucose in the bloodstream.

So, exercise lowers the blood glucose level. This brings about a reduction in insulin secretion. Lower insulin levels favour the release of glucose and fatty acids. The blood glucose level is maintained and the exercising muscles are provided with plenty of fuel for energy.

Exercise, blood glucose and insulin in people with Type 1 diabetes

People controlling diabetes with insulin injections do not have any immediate or fine control over their insulin levels (unless using an insulin pump). Let us look at what happens when you, someone with Type 1 diabetes, start exercising. To begin with, we will assume that you have taken normal doses of insulin, as usual, and that your blood glucose is running at near-normal levels.

Glucose, stored as glycogen in the muscles, will be used be up first. Then the muscles will start taking glucose from the bloodstream. Because insulin levels are normal (or even high) the liver does not release more glucose into the bloodstream. The relatively high insulin level in the blood also means that the muscles will use glucose as a fuel, in preference to fatty acids. The result is a falling blood glucose level, which will keep on falling unless it is topped up.

So, exercise causes the blood glucose to drop and this will cause potentially dangerous hypoglycaemia (low blood glucose) unless extra glucose is supplied from the diet. This means that you would normally need to eat extra carbohydrates when you exercise.

Now, let’s suppose that your blood glucose level is running high and you want to exercise. You may think (not unreasonably) that exercise will bring your blood glucose level down. Indeed, it may do; but it could also raise your blood glucose level even further.

Often, blood glucose is high because there is not enough insulin in the blood. If this is the case and insulin levels are really low then consider what may happen when you exercise.

Low insulin levels cause the liver to release glucose into the bloodstream and the blood glucose level rises. This happens even if blood glucose levels are already high.

Also, muscles will be using more fatty acids as a fuel instead of glucose. If fatty acids are burned in excess then by-products called ketones may build up. This causes the blood to become acidic and may lead to a potentially fatal condition called diabetic ketoacidosis, or DKA.

So, exercising when blood glucose levels are high (if insulin levels are low) can be dangerous.



Putting the theory into practise

To recap then, exercise usually causes the blood glucose level to drop. However, if you do not have enough insulin in your body, exercise can cause the blood glucose level to rise and you may be at risk of developing diabetic ketoacidosis.

Remember, your aim is to keep blood glucose levels close to normal wherever possible. Good control is not only important for your long-term health; it is also necessary for your safety and will aid athletic performance when exercising.

There are two ways to adjust for the effects of exercise:

  • by eating extra carbohydrates and/or
  • by taking less insulin

You will need to learn how to adapt your usual diabetes regimen in order to keep blood glucose levels well controlled when exercising. Your doctor and diabetes nurse will be able to help you with this.

Eating extra carbohydrates

How much extra carbohydrate is needed is a very individual thing. It will also depend on the length of time that you exercise for and how strenuous the activity is. You may need extra starchy foods at the previous meal and/or snacks or sugary foods before, during, and after exercising.

Use your blood glucose monitoring results to gage how much food you need to eat (and when) for that particular activity.

Make sure that you always have plenty of food available, including glucose tablets or a glucose drink, in case of hypoglycaemia during the activity.

Muscle cells will continue to take more glucose from the bloodstream for several hours after strenuous exercise. This means that you may be at risk of hypoglycaemia for up to 18 hours after exercising. Test your blood glucose level at regular intervals during this period and eat extra carbohydrate as required. Be sure to have a good bedtime snack after exercising in the evening.

Taking less insulin

You can adjust for exercise by reducing your insulin dose(s), however this should be done with caution. Consult your doctor or a member of the diabetes team; they will be able to provide you with specific guidelines for adjusting your insulin doses.

Do note that, having altered your dose of insulin, you are effectively committed to exercising. Remember that if your exercise class, training session or sports match is then cancelled you are at risk of high blood glucose levels. If this does happen you may need to find an alternative activity, or eat less in order to prevent your blood glucose levels from rising too high.

Trial and error

There are no magic formulas that you can rely on for perfect blood glucose control in diabetes. At the end of the day it comes down to learning what works and what doesn’t work – for you. Use frequent blood glucose monitoring. Make a note of your test results and the adjustments you have made to your diet and/or insulin and learn by trial and error.


Guidelines for exercising

Here are some simple guidelines which should hep you to maintain good control whilst exercising in a safe and enjoyable manner.

Blood glucose levels beforehand:

  • Do not exercise if your fasting (early morning) blood glucose level is more than 14 mmol/l
  • Do not exercise if you test positive for ketones in your urine
  • If your blood glucose level is less than 6 mmol/l you may need some extra carbohydrate before you start exercising

Blood glucose monitoring:

  • Test your blood glucose levels before, during and after exercise
  • Keep detailed records to help you identify when changes to your diet and/or insulin are needed
  • Learn how your blood glucose levels react to different types of exercise

Adjusting the treatment plan

  • Avoid hypoglycaemia by eating extra carbohydrates before, during and after exercising as necessary
  • Learn how to adjust your insulin dose(s) with guidance from your diabetes team

Exercise warnings

  • Check with your doctor before embarking on a new exercise regimen
  • Always include a proper warm-up and cool-down period (5 – 10 mins each)
  • Stick to low-impact exercise if you have neuropathy – cycling, swimming and rowing are all preferable to running or dancing
  • Wear comfortable footwear that fits well
  • Check your feet after exercising for any signs of sores or blisters
  • Make sure that glucose and carbohydrate foods are available at all times and wear or carry diabetic ID
  • Educate those around you about diabetes – the signs and symptoms of hypoglycaemia may be confused with those of over-exertion by someone who doesn’t know any better
  • Avoid exercising limbs in which you have recently injected insulin – this can cause the insulin to be absorbed very quickly, resulting in sudden or severe hypoglycaemia




Problems with insulin lie at the root of all types of diabetes. With Type 1 diabetes, it is a complete lack of insulin that is the problem. This type of diabetes results from the loss of the insulin-producing beta cells in the pancreas and daily insulin injections are necessary for survival.

To understand more of the relationship between insulin and blood glucose, take a look at “Living with Diabetes” and “Diabetes and High Blood Glucose”. Important information about insulins and injecting insulin can be found in the section “Using Insulin”. Here, we look at how insulin injections can be used to successfully control blood glucose levels in the management of Type 1 diabetes.

Good control of blood glucose levels is important for your health now and in the future. Understanding your insulin treatment will help you to take control of your diabetes. It will also help you to fit the diabetes into your life, as opposed to trying to fit your life around the diabetes.

There are a number of things that you will need to find out about. Most importantly, you will need to learn about your insulin regimen and how it relates to your food intake and blood glucose levels.

Insulin regimens

We often refer to ‘insulin regimens’ – but what exactly do we mean by this? It is the way that your insulin injections are organised through the day. Most people with Type 1 diabetes need more than one injection per day and use more than one type of insulin. The combination of insulins and the times that you have your injections make up your insulin regimen.


Your body’s insulin needs

Glucose is the body’s primary source of fuel; it comes from the food that we eat and is transported around the body in the bloodstream. Insulin enables the body’s cells to take glucose from the bloodstream. The cells might use it straight away or put it down to storage.

In people who do not have diabetes, insulin is produced by the body in response to the rise in blood glucose level that follows the digestion of food. This enables the body to either use or store glucose from the meal. The liver will take up and store a good deal of the glucose (it will then release it again later, when the body is fasting).

In addition to the spurts of insulin produced in response to eating, a trickle of insulin is released constantly, throughout the day and night. This looks after the body’s resting needs for insulin and ensures that cells can take up glucose (released form the liver) to keep ticking over.

Insulin therapy in people with diabetes needs to fulfil both of these needs. In other words, it should provide:

  • peaks of insulin at (or just after) mealtimes
  • background levels of insulin throughout the day and night

People with Type 1 diabetes usually need a combination of different types of insulin in order to fulfill these needs.

Dawn effect

The amount of background insulin needed by the body changes throughout the day. Different people have different patterns, but as a rule more insulin is needed during the morning. Some people find that they have trouble with high blood glucose levels when they wake up – this is because insulin needs increase in the early hours of the morning and is called the ‘Dawn effect‘. It is thought to be caused by an increase in the levels of other hormones circulating in the blood at this time of the day (these hormones have the effect of raising the blood glucose level).

People who do not have diabetes automatically produce more insulin when it is needed. People with diabetes need to try to counter the Dawn effect with appropriate administration of insulin (not always easy!)

Honeymoon period

If you have recently been diagnosed with Type 1 diabetes, you may still be producing a little insulin yourself. This is because diabetes generally occurs before all of the beta cells in the pancreas have been destroyed. Often, the few remaining cells will produce insulin for a few weeks or months and you may not need to inject much insulin at all. How long this ‘honeymoon period‘ lasts depends on how fast the beta cells are being destroyed by your immune system (see “Causes of Type 1 Diabetes”, for more details). The honeymoon period tends to last much longer in adults.

When the honeymoon period is over, the amount of insulin that you need to inject may increase dramatically. You may also find that controlling your blood glucose levels becomes much more difficult.


Types of insulin regimen

There are numerous types of insulin regimen. Ideally, you will develop an individualised regimen that fits in with your life. However, your diabetes team will probably start you on one of the standard types of insulin regimen – this can then be adapted later, if necessary.

Twice-daily mixture of short acting and intermediate or long acting insulin

This type of insulin regimen is sometimes referred to as ‘conventional’ therapy. Generally, a mixture of short and longer acting insulin is given in the morning and then again before the evening meal. Insulins are either drawn up from different bottles into the same syringe, or pre-mixed insulin (often supplied in pen injectors) is used.

How does the regimen work?

In theory:

  • the morning short acting insulin takes care of breakfast
  • the morning longer acting insulin takes care of lunch
  • the evening short acting insulin takes care of the evening meal
  • the evening longer acting insulin takes care of overnight insulin needs

One obvious advantage is that no injection is required at lunchtime – this is useful for many people, including school children.

A disadvantage of this type of insulin regimen is that mealtimes become very important (especially lunch and the evening meal) and snacks are often needed in order to prevent hypoglycaemia (low blood glucose) between meals.

Another disadvantage, again relating to lack of flexibility, is that if pre-mixed insulin is used, it is harder to vary the insulin dose to accommodate changes in your daily routine. This is because the doses of short and longer acting insulin cannot be varied independently of one another. So, if you want more (or less) short acting you will need to have more (or less) long acting too.

[Note: To a certain extent, the consequences of changing insulin doses will depend on the ratio of the two insulins in the mixture.]

Of course, an advantage of using pre-mixed insulins is that they are available as disposable pen injectors – this means that insulin does not need to be drawn up with a needle and syringe – it is quick and easy, and definitely more convenient.

Multiple daily injections of short or fast acting insulin with one or two separate injections of intermediate or long acting insulin

This type of insulin regimen is sometimes referred to as ‘intensive’ or ‘flexible’ insulin therapy.

Generally, short or fast acting insulin is given before meals and longer acting insulin is given at bedtime. Sometimes longer acting insulin is also needed in the morning.

This insulin regimen is much more flexible. Although a lunchtime injection is usually required, the use of a pen injector can make this a quick and easy task.

How does the regimen work?

In theory:

  • the short or fast acting insulin takes care of meals
  • the longer acting insulin takes care of background insulin needs

This type of injection regimen provides a supply of insulin that can be tailored more closely to the body’s natural needs. It also increases flexibility in terms of mealtimes.


Putting the theory into practise

Knowing how things are supposed to work is just the first step. Living with diabetes in real life means that you often have to relate what does happen to what should happen.

We are all different. Not just in terms of our hair colour or the shape of our noses – our body chemistries work differently too. With respect to diabetes, this means that what works for one person often doesn’t always work for another. It means that you will have to find out what works for you – and how it works for you.

This is where blood glucose testing comes in. Only by testing your own blood glucose level on a regular basis will you be able to see how well your insulin regimen is working and identify any problem areas.

Factors complicating insulin therapy

Unfortunately, insulin therapy in diabetes is far from the perfect solution, especially when the insulin is injected*. There are a number of things which can affect how your insulin behaves. In most cases, if you are aware of the possible factors that can complicate matters, you will be able to take steps to minimise any problems.

Absorption of insulin from the injection site

There are many things which can affect how the insulin is absorbed from the injection site into the bloodstream. Ideally, you need to be able to rely on your insulin being absorbed in a regular fashion from one day to the next.

  • It is important that the correct injection technique is used. If the injection is too shallow (into skin) or too deep (into muscle) the insulin will not be absorbed properly.
  • Insulin is absorbed most rapidly from the abdomen, then the arms, thighs and buttocks. Short acting insulins are best injected into the arms or abdomen.
  • Problems at the injection site itself can affect the absorption of insulin (see “Using Insulin” for more details).
  • Smoking can cause unpredictable or erratic blood glucose levels in some people. Nicotine causes changes in small blood vessels and this, in turn, can affect the absorption of insulin from the injection site.
  • Heat, massage and exercising a limb close to the injection site can increase insulin absorption. Sometimes this can cause a sudden drop in blood glucose levels and an unexpected hypo.

Unfortunately there is often some day-to-day variation in insulin absorption, even when using the same injection site; this is more notable with some of the intermediate and long acting insulins.


Exercise can have a number of effects on blood glucose levels, depending on the duration and intensity of the exercise, as well as your food intake and insulin levels.

Variable lifestyle or work schedule

Appropriate timing of insulin injections and meals is essential for good control. Sometimes though it is not easy to time insulin and meals to perfection and this is especially true for people who lead active or variable lifestyles or work variable hours.

It usually possible to work out ways to get round these problems but it does require commitment and lots of blood glucose testing on your part, as well as support from your diabetes team.

Weekends and Holidays

It is often the case that we follow quite different schedules when at home compared to when we are at work. If your routine is significantly different at weekends from weekdays then you may need to develop two insulin regimens that are tailored to your activities.

Holidays are all about leaving the stresses and strains of everyday life behind, relaxing and enjoying yourself. Any change in circumstances can affect your insulin needs and going on holiday is no exception. However, there is no reason whatsoever why diabetes should get in the way of having a good time on holiday; just remember to be aware of your needs and don’t neglect your diabetes completely.

*Providing insulin continuously with a pump can overcome some of the above difficulties (although it does introduce a new set of potential problems!) – see “Using Insulin“, for more information.

Summary of the main points to consider

  • Types of insulins used
  • Timing of your injections
  • How your insulin regimen is matched to your body’s natural insulin needs
  • How insulin is matched to food intake
  • Choice of injection site and other factors affecting the absorption of insulin
  • Using blood glucose monitoring results effectively
  • Making appropriate adjustments (e.g. to insulin dosage) to cater for changes in the daily routine (e.g. exercising)



Sick Days

Illness can play havoc with your diabetes. You will need to pay special attention to your blood glucose levels when you are ill and may need to make some changes to your usual diet and insulin doses.


Illness and insulin

When we are sick our bodies are under stress and this leads to the release of a number of hormones that can raise the blood glucose level. For this reason you may need significantly more insulin during periods of illness or if you have an infection. Watch your blood glucose levels carefully, testing every 3 or 4 four hours.

Diabetic ketoacidosis (DKA) can develop if insulin levels are not sufficiently increased during illness. Test your urine for ketones.

Never reduce or stop taking your insulin – even if you are not eating much.

If you have very high blood glucose levels or test positive for ketones then contact your doctor immediately. Drink plenty of fluids (sugar free).


Illness and food

You may not feel like eating your usual diet if you are unwell. That’s OK. You can replace your normal foods with sugary drinks or foods that slip down easily – soup, ice cream, yoghurt or custard, for example.

Keep an eye on your blood glucose levels – you may be able to spread out your usual food intake, having little and often.


    Sick-day action plan

  • You and your diabetes team should prepare a sick-day plan – a set of guidelines to help you manage your diabetes whilst you are unwell. This should include advice on the following:
  • Testing your blood glucose levels
  • Testing your urine for ketones
  • Adjusting your insulin doses
  • Foods that can substitute your normal diet
  • When to call for help
  • Who to call for help or further advice if you are worried