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Getting Started with a Ketogenic Lifestyle

The diet of the ketogenic lifestyle is not difficult to get your head around. It is not difficult to prepare meals. It does not have to be expensive. If you ‘can’t cook, won’t cook’ or you are on a tight financial budget, click here for suggestions.  The keto diet should be thought of as a lifelong commitment. Of course, there is room to be flexible. But if the basics are learned early and become a habit, then you have total control in managing diet and insulin.  How you choose to go keto depends entirely on your personal situation. Some people go the whole hog from day one; others go one meal at a time. It’s whatever works.  

The object of the ketogenic lifestyle is first and foremost to control glucose levels to ensure that blood glucose stays in the normal healthy non-diabetic range for the maximum amount of time. And also, the peaks and troughs of glucose will smooth out, which is a good thing.  If you have very high and very low glucose, the average might be quite good. This will be reflected in your HbA1c, which is a measure of longer-term control. But smooth control is better. It is safer, and people are starting to think that the less your glucose strays from the average, the better. Coefficient of Variation and Time in Range is becoming to be seen as more accurate measures of diabetes control. It requires a CGM (continuous glucose meter) to make these measurements.  

The benefits of smoother glucose control will be a reduction in hypos and a reduction in hypers with a decrease in diabetic ketoacidosis.  

Weight loss is not the intention of this diet, but many people who have weight problems will tend to gravitate to their naturally healthy weight. 

A ketogenic diet is not a calorie restriction diet.  Because you are not restricting calories, you should not feel hungry. You are only restricting carbohydrates and replacing the energy with protein and fat.  

So how is it done in principle?  

Adopting a  ketogenic diet consists of 3 Steps. You will be familiar with all of them due to your usual management of Type 1 diabetes. It is common to forget the training and then get into a routine that works for you to keep out of trouble. If you are finding that your HbA1c is higher than ideal (and this is the case in 95% of Type 1 on conventional management), then you should book with your specialist for a revision of the basics. This also applies to a keto diet.  

 Step 1  

Ensure that the basal dose of insulin is accurate. This is the insulin you take once or twice daily and is unrelated to mealtimes. It is the insulin injected to counter the rise of glucose that is generated, not through the diet but by the background metabolic processes that raise glucose.  Insulin works against a hormone called glucagon. If insulin is low, then glucagon will be high. If glucagon is high, then glucose is high. If insulin is high, glucagon is low.  If glucagon is low, then glucose is low.  

If there is an imbalance of insulin and glucagon, then the glucose level will be high or low. We need to use the basal insulin in the correct dose to get in balance with the glucagon. Glucagon in Type 1 is likely to act whether or not you are eating. So you need some background insulin for this reason.  

Step 2   

Revise how to count carbs and read the labels on food packets. There is so much sleight of hand played by food advertisers that it is difficult to know what food is healthy. There is a module to guide you through advertising speak. 

Step 3  

Rapid-acting insulin injection. Count the carbs and estimate the insulin dose to cover the carbs. It is the same method that you were taught at diagnosis. The main difference is that with small amounts of carbs, there will be low doses of insulin needed.  

Sound familiar? It’s the fundamentals of all Type 1 management. The only difference is the type of food you will be choosing. If you are using a pump, the basics are the same.  

Let’s go through this one step at a time. 

 Step 1.  Ensuring that the basal dose of insulin is accurate. This will differ depending on whether you are using a pump or injections. Mixed insulin ( Mixtard and all those types, often with a number in the name) will not suit a low-carbohydrate lifestyle. If you are on mixed insulin, call your specialist and explain your needs. There might be a good reason why they are recommending this specific formula.  

Those on a pump or basal-bolus regimens will need to assess their basal insulin requirements. The principle is to measure glucose during a fasted state. Then you will be sure that your basal insulin is just covering the glucagon and not any food. 

 The best and safest time to start is on waking. Miss your breakfast and measure your blood sugar. Ideally hourly. Keep your pump at its usual basal rate. Or inject your basal through a pen as usual. Many people with Type 1 need to inject basal insulin twice a day. Start with what you are used to and refine later.  

 The dose of basal insulin that most people are taking is probably close to the optimum, as it will have been perfected over months or years by trial and error. The optimal basal dose should be calculated independently of food. So, you can see quite clearly that by injecting your regular dose of basal insulin and then not eating for a while, your blood glucose levels will tell you if your basal dose is right. The test can only be done when you are fasting. Skipping breakfast is usually the most comfortable option. Test your blood glucose as often as you can during this period. Ideally, you should test with a continuous glucose meter or a flash meter (CGM), but in the absence of this, hourly testing with a finger-prick capillary glucose meter will do the same job. CGM are now available to all people with Type 1 diabetes, so call your specialist and get one if you can. They are not difficult to apply or to use and work with a mobile phone.

What you are looking for is blood glucose that is stable at around 4-6mmol/l. A rise or fall in your glucose levels throughout the basal testing will indicate if you are taking too much basal, in which case the glucose will trend downwards towards the hypo end. It might be that you will need to take glucose if you have a hypo. Then you can abandon the testing at this time and redo it again another day. 

 When you can get a full profile, it is time to analyse it.  If your blood glucose is rising, it means that you have an insufficient dose of basal insulin. Next time you do the test, you might need to increase it by a unit or two at a time until you get it right. If your blood glucose is reducing, it means that the basal dose is too high. If there is a flat trace, the dose is perfect. If you need to adjust the basal insulin dose, estimate the required correction and repeat the fast.   

You will then be confident that your basal insulin dose is accurate. It might need a revision later, but you can be confident for now that you have your basal set up. One thing to remember is that some people can get a spike in blood glucose in the early hours or after waking. This is typically due to various hormones working against the insulin. Usually, Growth Hormone, Adrenaline, and Cortisol can cause this.  Growth Hormone is a hormone that has a pulse action throughout the night and prevents insulin from working. So the blood glucose can be raised on waking. This is called the Dawn Phenomenon or Dawn Effect  It is more common in younger people, especially during growth phases, hence the name!  Adrenaline and cortisol are stress hormones that can raise blood glucose. You might have found that on getting up in the morning that your glucose rises even before you have had any food or drink. That is likely to be caused by stress hormones. With experience, you should be able to work all of this out. Stress and Dawn Phenomenon is best managed by a tiny dose of a unit or two of rapid-acting insulin. The basal dose is too slow to act in these cases.  

When you are basal testing, try to cover the full 24-hour period. Continual fasting is asking a lot. 2 periods of 12 hours might be manageable. Or three periods of 8 hours. Each time you start the exercise, you must ensure that you have taken no rapid insulin in the previous 5 hours. If you have any rapid-acting on your body, it will potentially confuse the results. Some of the modern ultra-rapid insulins like Fiasp might not last 5 hours. But 5 hours guarantees that your paid insulin will not be active.  

 Always do your basal tests in conditions that are entirely typical for you. Don’t complicate your basal testing with unaccustomed strenuous exercise or unaccustomed stress. Infection or a change in your usual daily routine will equally not produce accurate results. 

Once you have your basal set up correctly, steps 2 and 3 are easy.  

The final steps of counting carbs and calculating insulin are far more manageable when you don’t have to worry about the carbs in the meal. Small amounts of carbs mean small amounts of insulin, which in turn means more safety. Because of your very low-carbohydrate diet, your total daily insulin requirements will reduce. It will be mostly the rapid-acting insulin that is reduced because of the reduction in carbohydrates. 

 There is no exact figure for insulin reduction, but as a general observation, most people will halve their daily insulin requirements.  You may want to try reducing your carbohydrate intake one meal at a time, say breakfast for one week. Then add the evening meal or lunch. Or equally, you may want to go all-out and start eating less than 30 grams of carbohydrates from day one.  It doesn’t matter as long as you continue to learn from your meals. With a pump, the principles are the same.  Bolus your rapid-acting insulin to cover your carbohydrates. 

 When you have become well-practised in managing carbohydrates with a very low-carbohydrate diet,  you should find that you will have good control of your diabetes, often for the first time in your life. And once the ‘noise’ of carbs has been quietened, the more subtle effects of diet on diabetes will become apparent. Look for this in the module on protein.