Book 34: The Obesity Code

Dr. Jason Fung's The Obesity Code  is the first book I've seen that acknowledges the complexity of obesity.  Fung asserts that obesity is 70% controlled by hereditary factors and 30% by our choices.  He begins by pointing out the problems with the assumptions underlying the calorie reduction error.

• Calories in and calories out are not independent of one another
• Basal metabolic rate is not stable.
• Hunger and satiety are regulated by hormones not simply by conscious control.
• Fat stores are also hormonally regulated.
• Not every calorie is created the same.

This means that simply reducing calories fails when the body reacts by lowering metabolism and increasing hunger signals causing the cycles of weight loss followed by weight gain as the body tries to maintain its set weight.  Similarly, while exercising is important for many health reasons, trying to lose weight just by exercising also has its limits.  Increasing exercise also increases the hunger signals from the body.  The problem then is that the hormonal systems of the body sets the body weight and amount of fat too high, so long term weight close and control require that we reset the point.

The primary hormones that effect weight are insulin and cortisol.  In order to lose weight, insulin levels must be lowered.  To do this, he recommends no more than three meals a day (no snacks) and periods of intermittent fasting. Diet steps include:

1. Reduce the consumption of added sugar.  (Artificial sweeteners are also out because they raise insulin even more than sugar.) 
2. Reduce the consumption of refined grains.
3. Moderate protein intake.
4. Increase consumption of natural fats.
5. Increase consumption of fiber and vinegar both of which decrease insulin spikes.

While he mentions a few diet plans, he does not choose one over the other as long as they fit with his basic framework.  The importance of intermittent fasting is to lower insulin levels to reduce insulin resistance and reset the body's set point.  The appendix includes to sample one so fasting plans as we were to common concerns regarding fasting.  He also as a very brief section on the importance of reducing stress through regular exercise, meditation, and sufficient sleep.

Overall I thought the book was clear and we'll reasoned.  An excellent read for those wanting to lose weight. 5 stars.