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What to Eat – Information about food types

The following information is also available as Module E4/P3 in our Essential and Advanced courses for Healthcare Professionals.

This section is about converting to a ketogenic diet for someone with Type 1 diabetes, whose honeymoon phase has ended, and they have normal renal function. It has been mentioned elsewhere in this course that it is impossible to pigeonhole the management of Type 1 diabetes. The challenges change with the condition. Someone recently diagnosed with Type 1 might need to consider a diet adapted to help tackle the autoimmune disease. However, the science of what this might be is still in its infancy, but such a diet does exist. For someone with chronic renal failure stages 3 and beyond, a diet suitable for this condition is likely to be different. It can still be still ketogenic but more nuanced to renal support. The principles in this module are for the vast majority of people with Type1 who are not in these categories.

Diets for people with Type 1 Diabetes follow the same principles as all low carbohydrate diets: real food, healthy fats, and reduced carbohydrates. In the case of the ketogenic diet, carbohydrate restriction will be reduced to 10% of recommended or around 30g of carbohydrate per day. Because 1g of carbohydrate provides 4 calories of energy, this equates to just 120 calories of energy per day from carbohydrates. 

The modules on macronutrients and metabolic pathways provide all of the information required to understand why this is a safe practice. The rest of the dietary macronutrients will be made up of protein and fat. Protein can be consumed at between 1-2g per kg of ideal body weight depending on the physical activity and growth stages of the body. A reduction in this amount might need to be considered for people with renal disease. Fat will constitute the remainder, and healthy fats are recommended. (see below). 

The ketogenic diet is nutritionally complete and contains all of the essential amino acids, fatty acids, vitamins and minerals, and fibre required for healthy living. In common with all diets, a ketogenic diet can be as simple as you want it to be. However, it does not have to be, and thousands of recipes are appealing to all senses, visual, aroma, taste and texture.

There are some links to ketogenic diets provided below. 

For the clinician, it is good practice to follow this type of diet yourself for a month so you will have a good idea about what to expect from the shopping, preparation and recipe perspective. And also, the challenges of any of the transition periods and the metabolic benefits in terms of clarity of thought and feeling more energetic seem common to anyone following a ketogenic lifestyle. 

It is obviously up to the person transitioning to determine their speed of transition. This will be dictated by the enthusiasm and self-efficacy of the person and their clinical situation. There is an advanced module about introducing a ketogenic diet to someone with complications of diabetes, but it is not required for this course.

The following information is also suitable for patients and is included on the general website.

There is no science behind three meals a day. This has evolved around social habits and working patterns. Two meals a day followed by a fast of 16-18 hours is often practised by those eating low carb. It is perfectly safe in Type 1 on a very low-carbohydrate diet with careful blood glucose monitoring. (see module on fasting and autophagy) . Avoid snacks if you can. This practice will likely be the most challenging as snacking is widely practised in managing Type 1 diabetes on a high carbohydrate diet.  You might not be hungry at all, likely bored, sugar-addicted, stressed, or dehydrated.

Getting the proportions of nutrients right


Reducing the carbohydrate content in the meal makes sense to increase the chance of getting the numbers right. Smaller insulin doses lead to smaller swings of blood glucose, which reduce too-high and too-low blood glucose levels, leading to better and ultimately safer control. It is fortunate that of all macronutrients, it is a carbohydrate that is the only non-essential macro-nutrient. It is also fortunate that this non-essential macro-nutrient is by far the most likely to raise blood glucose. So, removing most carbohydrates from the diet can significantly affect glycaemic control without leaving the patient nutrient deficient.


Protein also raises blood glucose but, to a lesser extent and takes longer to achieve that effect. On a higher carbohydrate diet, its effect is masked by carbs but will become apparent with the move to lower carbohydrates.


Fat has a minimal effect on blood glucose levels, so it is easy to replace carbohydrates with fat.

Ketogenic diets based on real food are nutrient-dense. Fat and protein contain more than enough nutrients to replace those lost in reducing carbohydrates. But it must be emphasised that low carbohydrate diets are not zero carbohydrate. There will be carbohydrates in the fibre of leafy green veg, sugars in some of the fruits, and starch to some extent in nuts and some of the more starchy vegetables, but the latter are usually avoided. 

Leafy Green Vegetables

All green vegetables and salads are great. Eat as much as you want. Try substituting mash, pasta, or rice with vegetables such as broccoli, courgettes, cauliflower, or green beans in their place.  Cauliflower can be made into a rice substitute.  Pizza can be kept in the diet by substituting the carbohydrate-dense base with a cauliflower version. Courgettes can be a substitute for spaghetti if they are spiralised.

Root vegetables generally contain significant amounts of carbohydrates, especially potato and parsnip. Swede and carrot are less carby, but you do need to count the carbs. Celeriac is low in carbs. Again, count the carbs.


Meat, preferably the fatty, cheaper cuts, is excellent food on a very low-carb diet. Offal such as liver, kidneys, and heart are often overlooked but are full of nutrition and extremely cheap.  Eggs (three eggs a day is not too much) and oily fish such as salmon, mackerel, tuna, herrings and sardines are all great sources of protein and can be eaten freely.

According to the WHO, the absolute minimum requirement for protein is 0.61g/kg of ideal body weight. This is the minimum protein required long term to prevent overall protein loss. Various organisations have added a ‘safety buffer,’ and 0.75-1g/kg is often quoted. This is the recommended amount to consume to maintain weight and preserve muscle mass. Experts in nutritional ketosis have recommended slightly higher amounts of protein, 1-2g/kg of ideal body weight. Some people might have other reasons to eat more than this. Children and growing adults, pregnant or breastfeeding women, and those looking to gain muscle mass for whatever reason should consume more protein.

Healthy Fats

Healthy, naturally occurring, and unprocessed fat-containing foods are okay. Fats usually come as part of food such as cheese, nuts, and oily fish. It is often said that fat comes along with protein. So if you choose a protein, there will mostly be fat accompanying it. Various unprocessed fats are a source of the fat-soluble vitamins A, D, E and K.

Olive oil is especially useful. Butter is a better choice than margarine. Avoid margarine as it is a processed food with additives.  Coconut oil is excellent for frying, as is olive oil. (Processed vegetable and seed oils are not the healthy options once believed).


Some tropical fruits like bananas, oranges, grapes, mangoes, or pineapples are very carby and should be avoided. Berries are better and can be eaten in small amounts. A lightly cupped handful of around ten blueberries or 2-to 3 strawberries is acceptable. But count the carbs. These things can soon add up over a day.  There are many other berry fruits. Apples and pears must be carb counted as some varieties are overly sweet. Fruit juices are to be avoided.

Snacks and Treats

Try to avoid snacking if at all possible. The occasional treat of dark chocolate (85% cocoa or more) in small quantities is fine to have if the carbs are allowed for. When sugar intake is reduced or stopped, many people find their tastes change, and higher cocoa chocolate becomes the most enjoyable. Nuts such as almonds, macadamia, walnuts, pecans, hazelnuts, and brazil nuts are the less carby options. Cashews and peanuts can be higher in carbs. You will need to count the carbs as they are easy to overeat. Be mindful that snacking is causing continual stimulation of the digestive system. This might lead to glucose swings and possibly insulin resistance. Best to stick to mealtimes, if possible.

Processed Meat

Processed meats such as bacon, ham, sausages, or salami are okay. They are not as healthy as unprocessed real meats because of the additives used in the processing. The scientific consensus on their acceptability changes almost daily, so eat meat fresh if you can. 


Cheese is an excellent source of healthy fat. Bear in mind it is easy to consume a lot of calories when eating cheese inadvertently.



Sugar needs to be cut out completely in cakes, biscuits, cereals, and snack bars. Yes, even those so-called ‘healthy’ ones (marketing again).

Table sugar contains 50% fructose. Fructose, even though it is a type of sugar, does not stimulate insulin secretion. The high quantities of fructose consumed nowadays lead to insulin resistance and non-alcoholic fatty liver disease (NAFLD). While this is mostly associated with type 2 diabetes, it also complicates the management of type 1 diabetes. If you have had Type 1 for over a decade, then you will likely have some insulin resistance because of the higher quantities of insulin injected to cover unnecessary carbs. If you have gained too much weight, you will likely be insulin resistant.

Beige Carbs

It should be your goal as someone with Type 1 diabetes to aim to cut out obviously carby foods. There are unavoidable carbs in so-called low-carb foods, and adding carbs will make it challenging to reach keto levels every day. Carby foods include bread, pasta, and rice, including whole-grain versions of these foods, as they will still increase blood sugar levels to the same degree, albeit over a slightly more extended period.  There are substitutes. Rice can be made from cauliflower. Linseed can be used in a bread mix. See the recipe pages.


Sweeteners have been shown to increase hunger and may make weight loss more difficult. ‘Natural’ sweeteners such as Stevia, erythritol, and xylitol will not raise blood glucose in most cases. Artificial sweeteners such as Saccharin, Aspartame Acesulfame, and Neotame have zero calorific value but can cause insulin resistance. They are many times sweeter than table sugar and can fool the brain into preparing the bowel to digest carbohydrates even though there are none in the meal. 


Many alcoholic drinks contain significant amounts of carbohydrates. Beer contains the same amount of glucose as a slice of bread. But low-carb beers are becoming available. Another choice would be the occasional spirit. Take care with mixers, which often contain a lot of sugar. Use low-calorie mixers if needed. Go for extra dry prosecco, which is the lowest carb of any wine at 1%. A full-bodied red could be up to 5%. The best red choice might be pinot noir. The best white wine choice would be a dry sauvignon blanc.

Be aware that alcohol itself blocks glycogenolysis and gluconeogenesis. This means that alcohol blocks the body’s ability to raise blood glucose in a hypoglycaemic attack. Grain and fermented grape drinks, such as beer and sweet wines, can contain significant amounts of sugar. The combination of a glucose-raising substance, such as the grain in beer, and the alcohol, can make diabetes management quite tricky. 


The diet of the ketogenic lifestyle is not difficult to get your head around. It is not difficult to prepare meals, and it does not have to be expensive. If you ‘can’t cook, won’t cook’ or you are on a tight financial budget, there is an example of a two-week menu designed just for you! Click here

 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, you have total control over managing diet and insulin.  How you choose to go keto depends entirely on your personal situation. Some people jump right in, 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.  The average might be quite good if you have very high and very low glucose. 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 are now viewed 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 with weight problems 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 energy with protein and fat.

Type 1 Survival Tactics: Reading the Food Labels

This is from an article on the site for non-professionals. 

Firstly food labelling is an excellent initiative. We get the information we need about ingredients and the nutritional composition of our food. There is nothing wrong with food labels. But they are very misleading if we don’t know what we are doing. If the food labels were simply information, that would be perfect. But unfortunately, the dead hand of the retail industry has infiltrated the system. We have the front-of-pack labelling (fopl) that is intended to give us a quick reference. Those quick-reference traffic lights are meant to inform about the health-giving properties of the food. And the recommended daily allowance of each food group. But there are problems with fopl.

Ignore this!

The RDI or Recommended Daily Intake is based on the current dietary guideline recommendations. That is to say, they are based on a low-fat, high-carb diet. This is a diet where  50% of energy is derived from carbs. That is around 300g of carbohydrates per day. If this were a ketogenic diet the RDI would be 50g per day. So, the RDI does not fit our needs for fat and carbs.  Ignore RDI.

Worse for T1 keto is the traffic-light front of label information. Green for low fat, green for the high carb. That doesn’t suit T1 looking to get good control of their blood glucose. And more problematic for T1, who are not experienced with food labels, is the section on the front of the label that refers to sugars. It means sugar. Added sugar. It has no meaning regarding carbs. Sugar and carbohydrates can be separated into separate entities on food labels.  Unfortunately, the body is unable to do this. All carbs end up as sugar when digested. All starchy carbs end up as glucose. Separating sugar and carbs is not at all rational for people with Type 1 diabetes. 100g of porridge has 65g of carbs on the back of the label. But it states less than 1g of sugar on the front label. All carbohydrates break down into sugar. So, if we impulse-buy based on sugar, we will get caught out. Fair enough, the sugar is on the label to advise us about refined sugar. Because currently, there is a drive to limit our added sugar daily intake. But it is not helpful to people with Type 1 diabetes.  For Type 1’s looking to go very low carb, we must ignore the front of the pack. Turn it over and look at the back.

There, we need to look at carbohydrates. Carbohydrate is the number one ingredient that causes trouble for Type 1. Carbohydrates are mostly sugars. Starchy carbs are simple sugar molecules joined together. So, potatoes, bread, and cereals are virtually sugars but must be converted to sugar by the body. That is done in the digestive system. By the time bread gets to the bloodstream, it is sugar. The body has no clue whether it is sugar from ice cream or potatoes. It detects sugar. Root vegetables contain sugar, and leafy green vegetables also but in lesser amounts.  Vegetables are crunchy because of cellulose in the leaves and roots. It is sugar. However, some of the crunchiness comes from poorly digested carbs called fibre. More of that later.

So, when you go to buy a pack of food, go straight for the nutrition label on the back.

You have wisely ignored the claims on the front of the pack. But go back and take a quick look at the sugar content. Here is an example, 5.1g of sugar per serving. That seems low for a cereal.  Then take a look at the serving size. 30g. You will probably not be buying this food if you have Type 1 diabetes and are looking for very low carb. Weigh out 30g of breakfast cereal and look at the tiny amount in the bowl. No one eats that little. Especially a teenager. Manipulation of serving size is one way to ensure the figures are right. It is something to be aware of.

Now, turn over and look at the back of the pack. Find the line for total carbohydrates. The total carb will be your entire sugar intake from this food. This example shows 25g of carbs in a very small 30g portion. That is the sugar load you would get from this cereal even before you added the milk (but there are not many carbs in milk.) The front lists 5.1g of sugar and 25g of total carbohydrates on the back. That is five times the amount. Just 30g of this cereal would give you around three-quarters of your daily carbohydrate intake. However, looking at the amount per 100g of food is more realistic. You will then get a feel for the exercise and be better able to compare foods. Clearly, this cereal is not suitable for someone on a keto diet.  If you did not have T1 and were looking for 100-150g of carbs per day, this might be a good option for you. 

While you are around the back of the pack, take a look at the ingredients. Do you recognise the names of the ingredients? Do they seem like food? Are there added sugars? Are there added preservatives, emulsifiers, chemical names that you do not recognise, lots of E numbers, etc.? Many of the additives and processing chemicals there extend palatability and shelf life. If these are present, it’s best to avoid them. If ultra-processed food has a long shelf life, leave it on the shelf.

  We all like an unhealthy treat from time to time. It’s a personal choice in the end. Remember the adage. ‘It’s not what you eat between Christmas and the New Year that matters. But what you eat between the New Year and Christmas. But be careful! Some people on low-carb or keto diets will have sugar addiction or an eating disorder, and even a single day of unregulated eating, albeit with careful calculation of insulin dosage, may throw their eating pattern and blood sugars out of control for a prolonged period.

Ultra-processed foods are being increasingly recognised as harmful to health. They should, in the main, be avoided. The website  has a barcode scanner for food retail outlets to enable point-of-purchase evaluation of the degree of food processing. It is based on a scale called NOVA. There are many types of reference scales, but this particular one is used in research and so provides the best evidence-based reference at the present time. As a rule, avoid all NOVA 4 foods and aim for NOVA 1-2. 

On UK food labels, ‘Total Carbohydrate’, (sometimes simply labelled  ‘Carbs’) do not include fibre (which is unlikely to be absorbed). This is quoted separately. So, if you get 60g of carbs on the label, you get all 60g of carbs absorbed. For practical purposes and especially for a keto diet, where carbs make up only a small part of the diet, concentrate on ‘Total Carbs’ or ‘Carbs’ and disregard the fibre. (In USA keto recipe books and on USA packaging, you may see reference to ‘Net Carbs.’ In the USA, ‘Total Carbs’ includes fibre, which has to be subtracted to reach ‘Net Carbs’.)

Another complicating factor in all of this is the GI. That is the time taken for blood glucose to spike after a meal of just that food. The idea is that the lower GI, the less likely you are to get a sugar spike as the glucose will be absorbed more slowly. This is more of a tool for people with type 2 diabetes. If you are on a very low-carb diet, it’s okay to ignore GI unless you are going to have all your daily carbs in one go. Fortunately, the vast majority of real food is low GI by nature.

Sugar alcohols, such as erythritol or xylitol, are commonly used in low-carb diets as sweeteners. They are sweet to taste and although they are carbs, they are poorly absorbed. This varies, and some sources recommend allowing for half the carbs quoted for these sweeteners or less. Erythritol seems to have less impact on blood sugar than xylitol. As a rule, it’s good to reduce artificially sweetened foods and drinks altogether. Everyone should experiment with mainly giving up sweeteners (and of course sugar) if possible.—Pet alert. Sugar alcohols are harmful to dogs and cats.

  Fructose or fruit sugar is a sweet-flavoured type of sugar. It is possible to buy powdered fructose, also labelled as ‘fruit sugar.’ This has been popular in the past because it has little impact on blood sugars. However, it is not good for the metabolism, and if regularly consumed, it can be a risk for fatty liver disease and insulin resistance. Most whole fruits and also honey provide both fructose but also glucose. As usual, you will be looking up their ‘Total Carbs’. In practice, only small amounts of fruit and very little or no honey are consumed on a keto diet. Fructose does not materially affect blood sugar levels. It is present in fruits. The quantities of fruit eaten with a very low-carb diet will contain glucose and fructose and will be counted as total carbs. But in practice, only small amounts of fruits are consumed on a very low-carb diet. For fruits, count the total carbs. Fructose in refined sugar, such as table sugar and high fructose corn syrup, is another story altogether. Because we are avoiding refined sugars, we can leave it there.

Most of the food eaten with any diet should be real, nutrient-dense, whole food. A diet that your great-grandmother would eat. It will not have been processed.

 A lot of these fresh products have no food labels. In this case, go to an app like and get your information there. Once you get used to it, you will not have to think twice. You will get a good knowledge of the carbs in the foods you eat frequently. For a start, keeping lists and adding up the daily total of carbs will be necessary, but with time it becomes second nature. The idea is to enjoy real nutrient-dense food as part of a very low-carb lifestyle. It is not about becoming label obsessed.