Ketogenic diets are used for weight management purposes as well as therapeutically for a number of chronic health conditions including epilepsy, metabolic syndrome, MS, chronic fatigue syndrome, Alzheimer’s, Parkinson’s and cancer. The diet is high in fat, moderate in protein and very low in carbohydrates. Most people burn glucose from carbohydrates as their main fuel source. When you are on a ketogenic diet, your body makes a metabolic shift and it switches fuel source from carbohydrates to fat becoming the main source of energy.
This is likely the way our ancestors ate most of the year. During the summer and autumn months, they would likely have eaten large quantities of carbohydrates, gaining fat to see them through the leaner winter months. In the winter, the stored body fat supplemented their more restricted winter diet.
Using fat as the main fuel is called ketosis. Our ancestors are likely to have spent a large proportion of time in ketosis. A high fat, moderate protein and very low carbohydrate ketogenic diet causes the body to behave in a similar way to periods of restricted food availability.
Between meals, during fasting and strenuous exercise, blood glucose levels fall and fatty acids are released from adipose tissue and can be used to fuel the cells - except brain cells which are unable to utilise fatty acids directly. Fatty acids are converted in the liver into ketone bodies which can be used by tissues, including the brain, as a source of fuel.
Restrict your carb intake and wave goodbye to sugar and processed carbs
In order for the body to switch to ketosis, carbohydrate intake needs to be low, but the threshold is very individual. The more metabolically challenged your body is, the less carbohydrates you are likely to be able to handle (referred to as insulin resistance or carbohydrate intolerance). When embarking on a ketogenic diet, try going below 50 grams per day of net carbs. Net carbs is the amount of carbohydrate minus fibre, so there is ample room to eat plenty above ground, leafy vegetables as the fibre content will offset the amount of carbs they contain. Some people may need to go lower initially, possibly as low as 20 grams of net carbs per day. Others can tolerate eating more carbs whist still remaining in ketosis.
Carbohydrates should come mainly from above-ground vegetables (below ground vegetables are more starchy and therefore give a higher glycemic response), some nuts and seeds and small portions of low glycemic fruit, such as berries. Sugar and processed carbs are a no-go. These have little or no nutritional value. Once you start thinking of food as cellular fuel, this type of food will no longer appear as desirable.
Fat is your friend!
It is important to eat plenty of healthy fats to stay in ketosis. These include avocado, avocado oil, extra virgin olive oil, organic butter and ghee from pastured cows, coconut oil and MCT oil. Nuts (macadamia nuts and pecans have the highest fat content), seeds and duck fat are other sources of healthy fats. Don’t overdo it on the nuts as they are high in Omega-6 fats creating an imbalance in the amount of Omega-3 (anti-inflammatory) to Omega-6 (pro-inflammatory) fats consumed. There are other sources of good quality fat that come packed with protein, such as eggs from organic pastured hens, wild oily fish and organic grass fed beef – think the unpopular fatty cuts rather than the lean muscle meat.
MCT oil - quick access to ketones
MCT oil, especially the type that only contains fatty acids of the 8-carbon atom variety (caprylic acid), is very effective as it circumvents the digestive tract, goes straight to the liver where it is converted into ketone bodies, providing you with quick access to fuel in the form of ketones. MCT oil has a neutral taste can be eaten off the spoon or added to coffee, tea, smoothies or to your food. When adding MCT oil to the diet it is best to start slowly by taking one teaspoon per day initially to avoid any unwanted gastrointestinal side effects. It is a great way to beat cravings when you are weaning off carbs. Take a teaspoon of MCT oil 1-2 hours before the time you normally have your carb-crash.
Don’t overdo it on protein
Avoid excessive protein intake as it can be converted by the body to carbohydrates. As a rule of thumb, aim for between 0.8 to 1.2 grams of protein per kilogram of lean body mass, depending your level of physical activity.
Fasting can be useful to help achieve and maintain ketosis as it is a quick way of lowering your blood sugar as well as offering a plethora of other health benefits. Intermittent fasting can easily be achieved, e.g. by skipping breakfast. If you feel hungry, add some MCT oil to your morning coffee or tea. Alternatively skip your evening meal – this is likely the healthiest approach as your body’s metabolism slows down towards the end of the day allowing it to concentrate on repair and regeneration. Choose the regime you are most likely to stick with and don’t fast if it makes you tired and angry!
Ensure that you embark on a nutrient dense ketogenic diet
When searching the internet, you will find some ketogenic diets which are high fat, but place little emphasis on the types of fats to be consumed (including processed and pro-inflammatory fats such as margarine, trans fats and vegetable oils e.g. sunflower oil) and also diets which give little consideration to vegetables. It is important to ensure that you have a high and varied vegetable intake in order to get all the micro and phytonutrients needed for optimal cellular function. Fill at least half your plate with an assortment of above-ground vegetables. They taste great sautéed with olive oil, butter or ghee!
Some people can feel unwell in the first few days of embarking on a ketogenic diet. This is referred to as keto flu and it happens when the body is not getting its normal “fix’ of glucose whilst not yet having switched metabolism enabling it to access fat as a fuel source. MCT oil may help here so that you avoid hitting the wall. In addition, the kidneys release fluid, resulting in the body’s electrolytes becoming depleted. This can be helped by ensuring that you eat sea salt and stay hydrated. Consuming some broth may also help alleviate the symptoms.
Choose quality produce!
A word on quality. It is imperative that you choose quality produce. This means organic if possible and always make sure that the animals you eat have been given a natural diet. You are not what you eat, but what the animals you eat have eaten! If eating beef, make sure it is grass fed, if eating chicken, it should be pastured (contrary to what some believe chickens are omnivores as they eat a lot of insects) and salmon should not be fed grains! As fat is now your friend, you can save a lot on the meat you buy by opting for the unpopular traditional, more fatty cuts. They taste great, too!
Benefits of a ketogenic diet
A ketogenic diet can reduce inflammation in the body. When we eat carbohydrate our blood sugar increases, creating a degree of inflammation in the body. Ketogenic diets can:
- lower blood sugar (and thus lower inflammation) reducing the risk of metabolic syndrome and associated diseases
- help control hunger (no more mid-afternoon carb-crashes when you find yourself desperately grabbing for a snickers bar)
- support weight loss given that you can access your body’s adipose tissue for fuel when in ketosis
- help control epilepsy – as early as in the 1920s the ketogenic diet was used to help children with epilepsy
- provide a steady flow of ketones to the brain, avoiding large spikes in blood sugar levels, resulting in improved mental focus
- promote neuroprotective activity in the brain. Studies have shown that ketones can promote antioxidant activity, helping to decrease free radical formation in the mitochondria, protecting the cells from oxidative stress and injury.
- be beneficial to people suffering from conditions affecting the brain as they may struggle to use glucose to fuel the brain, leaving the brain starved of fuel whilst glucose levels in the brain remain high, causing further damage
- improve physical stamina – ketogenic diets are used by some sportsmen for endurance events to avoid “hitting the wall” (we have access to a lot of fat on our bodies, but only have limited supplies of glucose)
- improve sleep, immunity, anxiety, mood and overall feeling of wellbeing.
If you have any questions about the ketogenic diet or are wondering whether it is the right approach for you, please do not hesitate to get in touch!