If you've never heard the term "benign dietary ketosis" (or BDK) before it's because Dr. Atkins made it up. The phases of his diet and their rational are as follows:Continued
1. Induction phase (14 days) - to correct "unbalanced metabolism"
· Unlimited fat and protein allowed
· Carbohydrate <= 20 grams per day (20 gms of carbohydrate is approximately the amount in one medium apple)
2. Ongoing weight loss
· Carbohydrate can be increased to a level that Dr. Atkins defines as your "Critical Carbohydrate Level for Losing" or CCLL. You determine this level by increasing calories from carbohydrate until you no longer lose weight than you back down from that level. Based on your "metabolic resistance" the range is anywhere from 15 or less (for high "metabolic resistance") to 40 - 60 gms of carbohydrate per day (for low "metabolic resistance"). Dr. Atkins also coined the phrases "CCCL" and "metabolic resistance".
3. Pre-maintenance phase
· Can deviate with additional carbohydrate containing foods, as above, as long as there is no weight gain.
· 25-90 grams of carbohydrate allowed per day; again, based on "metabolic resistance" and this time your CCLM (Your Critical Carbohydrate Level for Maintenance). However, if weight is gained it's back to the induction phase.
Ketosis is the desired state on Dr. Atkins' diet. He predicts that with drastically reduced carbohydrate levels and with your body in a state of ketosis (as evidenced by urine test sticks) you will receive the benefits of carbohydrate restriction. These benefits include an improved state of well-being, a decrease in hunger as well as the loss of pounds and inches. Carbohydrates are allowed back gradually but he recommends that you stay in a state of ketosis through the first two stages.
à Ketosis (as opposed to diabetic ketoacidosis) is a depletion of the body's glycogen stores. This causes more fat mobilization than oxidation and produces incomplete fat breakdown and an accumulation of ketone bodies. Excess ketone formation increases the acidity of body fluids. Ketosis is not a necessary condition for fat mobilization but rather the result of the low-insulin state that occurs when the diet is low in carbohydrate.3
à Dr. Atkins suggests that the state of ketosis decreases hunger; however, the effectiveness of ketones in inhibiting food intake has not been shown.4
à Ketosis can initially cause increased weight loss but this is most likely due to water loss. It is estimated that at best the energy lost by urinary excretion of ketones would equal approximately 100-150 calories per day. This would allow for an overall weight loss of 0.45 kg or 1 lb per month.3
There are reasons why ketosis causes increased water loss (and therefore additional weight loss at the beginning of the diet). First of all, diets very low in carbohydrates tend to promote a temporary sodium loss from the body. Secondly, a diet high in protein necessitates the kidney to excrete increased urinary water. Therefore, a low-carbohydrate diet causes increased water loss and can lead to dehydration.2 Olsson and Saltin demonstrated this by taking biopsies of human muscle after providing subjects a low carbohydrate diet. They repeated the biopsy after allowing them to maintain a carbohydrate liberal diet. They calculated a net change of 500 gm of glycogen, which contains approximately 3 to 4 gm of water per gram. The equivalent 1.5 to 2 liters of water agreed roughly with an observed 1 kg of weight gained during the time they were allowed a liberal carbohydrate intake.5
Additionally, the studies that Dr Atkins cites showing that higher fat diets caused greater weight loss lasted for only 4-8 days. When others studied similar diets for a longer period of time (18 to 24 days) the increased weight loss was no longer observed.2 Furthermore, all of these studies refer to a hypocaloric diet. In other words the participants were on diets of only 1000 calories. Dr Atkins mentions this yet still contends that the low carbohydrate, "metabolic-advantage" is the reason for the weight loss not the reduced calorie intake.
Dr. Atkins does go along with more traditional health recommendations in terms of exercise. He recommends that everyone increase their physical activity significantly adding that physical activity is essential for those with a "high metabolic resistance". He devotes an entire 7-page chapter to the benefits of exercise but never mentions that in terms of increased activity and exercise the body works most efficiently while consuming a diet with adequate carbohydrate.
In terms of low-carbohydrate diets, fatigue has been documented from World War II to the present. During World War II, pemmican, (an essentially carbohydrate free ration), was used by the Canadian Army. The troops became incapacitated within 3 days. Many complained of nausea and several vomited. By the fourth day they were dehydrated and listless. Their breath smelled of acetone, evidence of ketosis; but because of water loss and therefore rapid weight loss they couldn't function.2