The Ketogenic Diet, the Science and my experience so far

(Image courtesy of: http://guthealthproject.com/wp-content/uploads/2015/08/shutterstock_253462885.jpg)
The Ketogenic Diet is a method of eating designed to induce nutritional ketosis, the state in which the body switches its fuel source from glucose to fatty acids from the body. This is very beneficial to the body as we have thousands of calories of stored fat versus around a 24 hour supply of stored glucose. Ketosis is entered in times of fasting typically 48 hours and above, or through severe dietary carbohydrate (glucose) restriction with very high intakes of fat.
When carbohydrates are present in the body' it breaks them down into glucose immediately. If there is protein present it can convert that to glucose also through a process called gluconeogenesis, but this isn't preferred by the body as it would lead to the break down of muscle tissue which results in reduced immunity and nutrient storage, carbohydrates and fats are the preferred energy sources for the body. When there is under 50g of carbohydrates eaten for a few days, and protein levels kept low, the body switches to fueling itself through mobilising fat stores around the body. Fatty acids circulating the blood stream as fuel are called Ketones namely Betahydroxybuterate and Acetoacetate.
For the body to enter nutritional ketosis the diet must comprise mainly of fat, 75% is the ideal. So if the daily calorie requirement of an adult is 2000kcal, that means 1500 of those calories come from fat. Or 167 grams of fat. This really isn't a lot. A tablespoon of olive oil contains 14g of fat, so does 4 rashers of streaky bacon, and so does half an avocado, so right there a snack sized meal contains nearly a third of the requirement. Put those on a green leaf salad and add another table spoon of oil and thats well into a third of the requirement. I've been posting most of my meals on my instagram.
Fat has 9 calories per gram, compared with 4 grams in both protein and carbohydrate (there's 7 in alcohol), so the body meets its energy needs with less food gram wise. Ketogenic is a good tool for fat loss. In three weeks I have made noticeable reductions in my body fat levels prior to even being fully 'fat adapted'. A contributing factor towards the weight loss is calorie restriction, eating a little protein and a lot of fat with little to no carbohydrate drastically reduces the amount you eat, the meals leave you nutritionally full quicker and with a lower calorie intake. It is possible to over eat, but you really have to intend too! Fat also doesn't have an effect on insulin - the hormone which removes sugar from the blood stream after eating carbohydrate intake. The more carbohydrates ingested, the greater the spike in insulin will be and the greater the drop back to baseline levels will be and its in this drop where the body starts to crave energy, usually in the form of a sweet food with a direct source of glucose.
The insulin response is an inflammatory response. Inflammation is the breeding ground for diseases and unwanted affects within the body, it also has a damaging effect on the brain. Thats not moderate carbohydrate so much, like a portion of rice or quinoa, but it would be a couple rounds of bread twice a day with sugar based condiments and a fizzy drink.
In a meal, providing the calories from protein do not match or beat the calories from fat, a high fat and very low carb diet has little to no effect on blood sugar and consequently little insulin is released so there are very few peaks and troughs. I've found I have had no energy dips whilst in ketosis, even if I feel tired I don't seem to lose focus. Because of the low insulin response, ketosis is not inflammatory and this creates a very positive therapeutic environment in the body and it is being used as a therapeutic tool for many auto-immune diseases such as Type 2 diabetes and rheumatoid arthritis, as well as epilepsy.
There is also very promising research towards the effects of a carbohydrate restricted diet on the rate of development of cancer cells. It would be irresponsible of me to suggest anything close to proof, or factual statements. But, some of the evidence and hypotheses towards cancer cells requiring glucose for energy and being very inefficient at using ketone bodies for fuel is incredibly promising.
This is a very exciting article on the presence of ketones in the body slowing tumour growth, and even inducing cell death across a number of cancers.
This is another very thorough article evaluating the ketogenic diets potential therapeutic benefit to cancer itself, and as an aid to traditional cancer therapies. It draws from a lot of literature and several studies with links to many other studies. It also notes the fact that there are currently (as of the paper), 61 studies ongoing looking at the effects of a ketogenic diet and cancer.
This article is a brilliant post by a well known blogger and nutrition author, Jimmy Moore, who self experiments with the ketogenic diet, he documents his experiences here.
Endogenous ketones refer to ketones which the body produces itself, betahydroxybuterate and acetoacetate. These are the fatty acids produced in the liver in a state of ketosis. These can be measured with the blood meter which I use on my instagram, the levels of ketones present in the blood indicate the state of ketosis the body is in, above 0.5 mmol is light ketosis, between 0.5-2.0 is nutritional ketosis, and over 3.0 is deep ketosis. I have noticed my highest levels to be during fasting which I found incredibly interesting. I have been in ketosis for over two months with one day where I came out (I smashed a bag of fudges and 100g of dark chocolate and it felt like how I imagine crack cocaine would) and I was back in in 48 hours. I performed a 41 hour fast during the second period of ketosis and witnessed my highest readings yet, which indicates that when the body is deprived of nutrition, it will increase its energy production. I clocked out at 4.5 mmol which is very deep ketosis. People regularly sit at up to 7mmol so thats my next challenge!
As well as endogenous ketones, there are also exogenous ketones, ketones you take orally which work immediately, the most common form being MCT oil. They are very potent and the body needs to build a tolerance to them, the dose must be increased slowly otherwise nausea, vomiting, and dhiarrea are possible inflammatory responses to too higher initial doses. I found 1 tablespoon to be the limit initially and maintained two per sitting when necessary, I've yet to exceed two servings in a day. Other forms of exogenous ketones are Ketone Esters, and Ketones Salts, I haven't experienced either yet, but they are incredibly potent apparently, but for the most part they taste vile 😂 luckily and comfortingly, the ketogenic diet is a massive area of research and investment at the moment and there are many exciting new products becoming available which mimic things like gatorade but possess very potent ketone bodies, so holding out for them!
Ketoacidosis - one concern is for ketoacidosis, a potentially life threatening condition faced by type 1 diabetics experiencing rapidly elevated levels of ketones in the blood; the initial response towards ketosis from the medical community mostly seems to be the immediate fear of potentially life threatening levels of ketones in the blood known as ketoacidosis. There is no need for concern though, it appears ketoacidosis is night and day to nutritional ketosis. This is my understanding - Insulin is the hormone which manages blood sugar and ketone levels in the blood preventing excessive rises in both; Insulin relays signals to the brain on the levels of sugar and ketones in the blood, if blood sugar is too high it releases more insulin to clear it, and if it is too low for extended periods of time the body switches to releasing ketones for fuel. If insulin cannot be produced by the body as experienced with Type 1 diabetes, there are no signals sent to the brain and the body thinks it is being starved so begins to release ketones for fuel as in ketosis. When the body can produce insulin, ketone levels are managed in the same way as blood sugar, but without insulin the body will continue to produce ketones unrestricted. High levels of ketones are very acidic to the body and if unmanaged they become very harmful and will result in critical illness. In normal healthy individuals who can produce even a small level of insulin, ketone levels will not rise more than 10mmol and with great effort I have only experienced 4.5mmol, Ketoacidosis is in the range of 15-25mmol! This article is a good nerve calmer :)
I think the only way to know if a diet or nutritional method works is to try it. There is absolute merit in a balance and well rounded diet, applying the 80/20 principles is a tried and tested method. But to experience the switch to utilising fats is something unless intended on, we would never experience in our day to day lives. I have flirted with Keto before but without the blood reader I can't be sure how far in I was. This time round I was fully in ketosis, and I had average fasting ketone levels of 1.2-1.6 mmol sometimes higher. The blood reader and ketone sticks are essential, I use the On Call DK reader from amazon. It has been a 100% positive experience. There is such a wealth of value to the body to be gained from this experience, it has been fascinating, exciting, and definitely has had a positive effect on all areas of my life so I highly recommend :) embrace the fat ✊
These have been my fundamental resources for Keto: