Category: Blood glucose

The simple answer is maybe but unlikely. Adherents of the Keto Diet, a high-fat, low-carb diet, claim that it helps you reduce weight and can reverse your diabetes among many other health benefits. Is there much truth behind this contention?

As anybody who has read my book Beating Diabetes, or who follows this blog, knows: a sure-fire way to get your blood glucose down to manageable levels is to follow a diet that is low in sugar, low in fat, low in salt, high in fibre, made up of mainly natural foods with low GIs, while avoiding eggs and dairy products, washed down with plenty of water.  

The Beating Diabetes diet does not specify low carbs, only low sugar. Other carbohydrates, such as starch and dietary fibre are part of this diet.

The alternate diet, the keto diet is a high-fat, low-carb diet.

What exactly is it and how does it work?

What is a Ketogenic Diet?

The ketogenic diet (or keto diet for short) is a very low-carb, high-fat diet. It involves reducing carbohydrate intake drastically and replacing the carbs with fat.

This reduction in carbs puts your body into a metabolic state called ketosis, a in which fat provides most of the fuel for the body. It occurs when there is limited access to glucose (blood sugar), which is the preferred fuel source for many cells in the body.

To achieve ketosis, you need, as a general rule to eat less than 50 grams of carbs a day perhaps as little as 20 grams a day. To do this you must remove carb-heavy foods from your diet, such as grains, candy (sweets) and sugary drinks. You also have to cut back on legumes, potatoes and fruit.

When you eat a very low-carb diet, your insulin levels go down and fatty acids are released from your stores of body fat stores in large amounts. Much of these fatty acids are transferred to the liver, where they are oxidized and turned into molecules called ketones (or ketone bodies).

These molecules can provide energy for the body. Unlike fatty acids, ketones can cross the blood-brain barrier and provide energy for the brain in the absence of glucose. They can deliver numerous other health benefits, besides reduced insulin and blood glucose levels, as well as weight loss.

Different types of ketogenic diet

There are several versions of the ketogenic diet. These include:

• The standard ketogenic diet … a very high-fat, moderate-protein, and very low-carb diet … typically 75% fat, 20% protein and only 5% carbs
• High-protein ketogenic diet … this is similar to the standard diet but includes more protein … usually 60% fat, 35% protein and just 5% carbs
• Cyclical ketogenic diet … this diet alternates low-carb and high carb periods … such as 5 very low-fat days followed by 2 high-carb days
• Targeted ketogenic diet … this version of the keto diet allows you to add carbs around workouts

Only the standard and high-protein keto diets have been studied scientifically. The other two versions are mainly used by athletes and body builders.

But which foods exactly do you need to avoid, and which do you need to eat if you are following this diet?

Foods to avoid

You need to limit any foods that are high in carbohydrates.

This means that you should avoid carb-based foods such as:

• grains … wheat products, rice, pasta, cereal, etc
• sugary foods … sodas, fruit juices, ice cream, smoothies and sweets (candy)
• legumes … beans, peas, kidney beans, chickpeas, lentils and so on
• root vegetables and tubers … potatoes, sweet potatoes, carrots, parsnips etc
• most fruits … with the exception of berries

You also need to avoid low-fat or dietary products which are usually highly processed and are high in carbohydrates. In addition, you should ignore condiments and sauces that contain sugar and unhealthy fats. And you should eat very little processed vegetable oil, mayonnaise and similar foods which are choc-a-bloc with unhealthy fats.

Alcoholic beverages are also a no-no as they can throw you out of ketosis. Sugar-free diet foods can also affect your ketone levels especially when they are high in sugar alcohols … these foods tend to be highly-processed also.

Foods to eat

A ketogenic diet should be based on whole, single-ingredient foods that are high in fats and/or low in carbohydrates. Ketogenic experts recommend the following:

• meat … red meat, steak, ham, sausage, bacon, chicken and turkey
• fatty fish … such as salmon, trout, tuna and mackerel
• nuts and seeds … almonds, walnuts, flax seeds, pumpkin seeds, chia seeds, etc
• eggs … from free-range chickens
• butter and cream … from grass-fed cows
• cheese … unprocessed cheese such as cheddar, goat’s cheese, cream cheese, blue cheeses, mozzarella
• avocados … whole avocados or freshly made guacamole
• healthy oils … extra virgin olive oil, coconut oil and avocado oil
• low-carb veggies … most green veggies, tomatoes, onions, peppers, etc
• condiments … you can use salt, pepper and various healthy herbs and spices

Ketogenic diet and weight loss

Several studies over the last 15 years indicate that the ketogenic diet is effective in helping you lose weight. In addition, you lose weight without having to count carbs or track your intake of food.

One such study of 42 healthy but obese women, published in the Journal of endocrinology and metabolism in April 2003, found that people on a ketogenic diet lost more than twice as much weight as persons on a low-fat calorie-restricted diet. Their triglycerides and HDL levels also improved significantly.

Another study, published in Diabetic Medicine, a journal of the British Diabetic Association, in December 1007, of 13 subjects with type 2 diabetes and 13 healthy subjects found that those on a ketogenic diet lost three times more weight than those following the diet recommended by Diabetes UK. But there were no differences between the two groups in changes in their levels of HbA1c, ketones or lipids.

Being overweight or obese is an important factor in the development of type 2 diabetes. The fact that following a ketogenic diet is an effective way to lose weight suggests that this diet might be helpful in reversing diabetes.

Ketogenic diet and diabetes

A study in the Annals of Internal Medicine, published in March 2005 found that a ketogenic diet improved insulin sensitivity by 75%.

In another study published in Nutrition & Metabolism in December 2008, 84 volunteers with obesity and type 2 diabetes followed either (a) a ketogenic diet (ie <20g of carbs a day) or (b) a low-glycemic, reduced-calorie diet (ie 500 kcal/day less than a diet calculated to maintain their current weight) for 24 weeks.

Both diets led to improvements in HbA1c, fasting glucose, fasting insulin, and weight loss. Group (a) on the ketogenic diet had greater improvements in HbA1c, body weight), and HDL cholesterol compared to group (b) on reduced calories. Furthermore, diabetes medications were reduced or eliminated in 95.2% of those in group (a) against 62% of the participants in group (b).   

How the high-fat, low-carb diet works

Persons eating the standard Western diet obtain their energy from glucose. When they digest their food, glucose (which comes mainly from the carbohydrates in their diet) is released into the blood stream where it travels to the muscle cells. At the same time the pancreas releases insulin into the blood stream. The purpose of insulin is to open the receptors in the muscle cells so that the glucose can enter the cells to provide energy.

If you have type 2 diabetes, your basic problem is that these receptors are blocked with fat and the insulin cannot open the cell doors. Hence the glucose cannot enter the muscle cells and you end up with too much fat and insulin floating around your body and causing severe damage to your health over time.  

The trick to reversing your type 2 diabetes is simple. If you follow the Beating-Diabetes (low-sugar, low-fat) diet you will starve your body of fat and after a few weeks the receptors in your muscle cells will unblock, enabling glucose to enter the cells thereby ‘reversing’ your diabetes.

The effects of the high-fat, low-carb ketonic diet are entirely different. When you follow the keto diet, your body switches to using fat as its source of energy rather than carbs. This is known as ketosis, which involves the liver producing ketone bodies (aka ketones) out of fat and using these for energy instead of carbohydrates.

Ketone bodies or ketones (acetoacetate, beta-hydroxybutyrate, and acetone) are used in healthy individuals to provide energy to the cells of the body when glucose is low or absent in the diet.

Should you make the switch?

Though it is obviously effective in helping you lose weight and in all probability can enable you to reverse your diabetes, a ketogenic diet can have negative side effects.

Keto flu … is an unpleasant side effect that you may experience as you transition to a ketogenic diet. You may experience fatigue, dizziness, brain fog and insomnia. But those you have made the transition say that it passes after some time.

Nutritional deficiencies … the keto diet limits the kinds of food you can eat and entire food groups, such as beans, legumes, whole grains, as well as many fruits and vegetables are eliminated from your diet … many of these foods contain vitamins and minerals which you cannot get from any other sources. The keto dies is not a balanced diet so if you go this route on a long-term basis you need to take a wide range of supplements to make up for the loss of micro-nutrients.

Constipation … when you eliminate most fruits and vegetables from you diet you run the risk of becoming deficient in dietary fibre with the result that you become constipated. The solution is to add some low-carb, fibre-rich vegetables to your diet, such as asparagus (2% carbs), Broccoli (7%), Tomatoes (4%), Cucumber (4%), Cauliflower (5%), Eggplant (6%), Bell Peppers (6%) and Green Beans (7%).

Loss of electrolytes … as you enter ketosis, your body will start dumping its stores of glycogen (the main form in which glucose is stored in your body) through urination. An increase in how often you urinate will inevitably lead to a loss of electrolytes such as sodium, magnesium and potassium. These electrolytes are essential for cardiac function and a normal heart beat, and that loss can put you at risk of cardiac arrhythmia. To avoid this you should eat avocados, leafy green vegetables, asparagus and cruciferous vegetables which are natural sources of this electrolytes. Add a pinch of sea-salt to your meals to up your sodium levels. You can also take an over-the-counter supplement.

Dehydration … a keto diet is known as a ‘water flushing’ diet because the glycogen stores in your muscles and liver are reduced through urination. Thus, along with loss of electrolytes, dehydration is thus a real threat in the early stages of the diet. The solution is to drink copious amounts of water, at least 2.5 litres a day. The requirement to drink water is also a feature of the Beating-Diabetes diet.

Kidney damage … untreated dehydration can lead to acute kidney damage. In addition, high levels of nitrogen created by excess protein can also increase pressure on your kidneys, damaging the cells and leading to the formation of kidney stones. Thus, it is only sensible to seek medical advice before you embark on the keto diet, especially if you already have issues with your kidneys and liver.

Muscle loss … is a real possibility when you are in ketosis for a long time. While protein is the basic muscle builder, you muscles also need carbs for their formation and maintenance. Without those carbs your body starts to break down muscle. In itself this would not be dangerous for most of your muscle mass. Unfortunately, your heart is also a muscle, so it too could get damaged.

Low blood pressure … one of benefits of the ketogenic diet is that it can help reduce elevated levels of blood pressure. Thus, if you are already taking prescription medicines to control hypertension, it can cause abnormally low blood pressure levels, taking them so low that it can be dangerous, even deadly. The solution is to discuss whether you should reduce or stop your medications with your doctor and follow his or her advice.

When you consider the risks involved, the answer to the question is you probably should not switch … especially if the Beating Diabetes diet is working for you.