USEFUL: Longer Fasting Regimens. This is the seventh part of an ongoing series on fasting.

We covered fasting regimens using periods less than 24 hours in our last post. This post will cover those schedules that use fasts longer than 24 hours. . . .

For longer duration fasts, we often try NOT to calorie restrict during that eating period. Often, as people get used to fasting, we hear very often that their appetite starts to seriously go down. Not up. Down. They should eat to satiation on their eating day.

There’s a very good reason for this decrease in appetite. As you start to break the insulin resistance cycle, insulin levels start to decrease. Since insulin is the major regulator of the body set weight (BSW) your body now ‘wants’ to go lower. In response, hunger is suppressed and total energy expenditure is maintained. So – appetite goes down and TEE [total energy expenditure] stays same or goes up. Remember that standard Caloric Reduction as Primary (CRaP) strategies produce the opposite. Appetite goes up and TEE goes down. Which do you think will work in the long run?

Related: How Caloric Reduction Wrecks your Metabolism.

One of the key assumptions of the CRaP theory is that in response to caloric change, TEE does not change. This is clearly NOT TRUE. . . .

The body seems to have a certain Body Set Weight (BSW). Any attempts to increase above this BSW will result in our body trying to return the body to its original weight by increasing TEE (increasing metabolism to burn off the excess calories).

Any attempts to decrease below this BSW will result in our body trying to return the body to its original weight by decreasing TEE (decreasing metabolism to regain lost calories). No wonder it is so hard to keep the weight off! As we slow our metabolism, we must further and further reduce our caloric intake to maintain weight loss.

An important thing to keep in mind is that fasting is not an extreme version of mere caloric reduction. The two activities have very different effects on the body.

Earlier: Misconceptions about fasting.