Friday 20 September 2013

Fat Fast / Cream Day

Well here I am 3 years down the line, and still eating low carb. My current weight is 11 stone 10 lbs ( 164 lbs or 74.5 kg if you prefer other units ) which is as low as I've ever measured. I must have weighed this as a boy, but boys don't weigh themselves. My BMI is 23 !! Low carb delivers, and I haven't "put it all back on again" as various cynics, refuseniks, dietitians and general tossers on the internet would have you believe.

I dropped 8 lbs recently on a rather good and special holiday, more of which later.

About a month ago I did a sort of "fat fast" to try to boost my weight loss a bit and see if I could increase the ketone levels in my blood - aiming for the "nutritional ketosis" nirvana that people enthuse about on the web. I wrote it up as a document that you can read or download from Google Drive

Dr Atkins described a fat fast in his original book in 1972, used to kick start his diet in some resistant individuals who needed to have very low levels of carbohydrate and protein to cut down their blood sugar levels and get the brain switching over to use ketones from fat as its primary fuel. From memory he aimed at 1000 calories with basically all of them (90%) from fat - macadamia nuts and some cream cheese for example. A fat fast cookbook has been published recently, for those looking for detailed guidance, but I haven't read it yet.

My fat fast delivered a 3 pound weight loss in one day, and ketone levels increased progressively with the overnight fasted result up in the magic "nutritional ketosis" range :-

I think a fair chunk of the weight loss was water associated with glycogen, as the lack of carb intake and the day's activities would have depleted my liver's glycogen reserves and forced the use of glucose and ketones produced by the liver to provide the body's energy requirements (along with fatty acids from my fat stores, of course).

My total food intake for the day was 1480 calories, with 78% from fat and 71 grams of protein, so this was not a real "hard core" fat fast to the letter, but a decent amount of food with controlled protein, low carbohydrate and lots of lovely nutritious fats to scare the cardiologists away.

It's interesting that 40+ years after Atkins wrote his book "Dr. Atkins' Diet Revolution" , and 10 years after his death, people like me can re-discover his ideas and find they are still relevant. They may in fact still be "best practice"  despite all the low fat calorie restriction dogma we have been subjected to since.