On the Today Show in early January 2013, author David Zinczenco told host Matt Lauer that his new book, “The 8-Hour Diet,” described a way to lose weight based on “brand new science.” My wife told me about it but was a little vague about how it worked. So, I found the segment on NBCnews.com, and here’s what I saw: lots of goodies: yoghurt, berries, orange juice and bran muffin for breakfast, a big salad, two slices of pizza, cup of soup plus potato chips or French fries for lunch, and a big rib eye steak, potatoes, veggies and a piece of chocolate cake for dinner.
Zinczenco described the diet as “lean protein, good fats, and complex carbs” – the government’s good ole message. The only limiting factor was that all the food for any particular day had to be consumed within an 8-hour window: 9 to 5, 10 to 6, or even 11 to 7. The example given was 10:30 for breakfast, 12:30 for lunch, and 6:30 for dinner. The author said you could do this 8-hour diet for just 3 days a week and lose as much as 5 pounds a week and 20 pounds in 6 weeks. He tried it himself, he said, and lost 7 pounds in 10 days. He called it “intermittent fasting.”
So, I have to say this diet has obvious appeal for a “healthy” person with “normal” metabolism, Unfortunately, this EXCLUDES anyone with any of the indications of Metabolic Syndrome (see Retrospective #9). It is, however, clever merchandizing to sell a book on the Today Show to an audience of women who aren’t the least bit interested in the mechanism or counting – only in the eye-appeal of all their favorite foods and the comfort of not having to deny themselves anything except eating for 16 hours a day for three days a week.
Zinczenco points out that that’s not so tough either, since most people already fast between dinner and breakfast. To stress this point, he noted the word breakfast is composed of “break” and “fast.” He also spoke disparagingly of the practice many have today of “grazing all day long,” including sometimes after dinner. For three days a week, at least, that is a “no-no.” He also suggests a morning exercise routine (instead of breakfast) to burn up stored carbs.
But what’s the real physiological mechanism of the 8-Hour Diet? It works on the principle of the fed state and the fasting state, hardly a brand-new science. It is the basis of the hard scrabble existence of mankind on this earth from the beginning of time. You hunt, you eat, you rest while you digest, and then, when your body tells you that you need to eat again, you burn stored fat while you hunt again.
Quoting “certain conclusion” #2 from Gary Taubes’s “Good Calories-Bad Calories” (see Retrospective #5), your body regulates this “harmonic ensemble” to maintain homeostasis, This cycle continued throughout life and for 500 generations, until the advent of the Neolithic Era 10,000 years ago. The Neolithic introduced cultivated grains, grain storage, domesticated animals, and human settlements. It was a momentous development.
In the Paleo era, after eating, food is digested and absorbed. All carbohydrates and about half the protein we eat eventually becomes glucose, the latter through a process called gluconeogenesis. This is a glucogenic or fed state.
The fasting state begins when the glucose energy from the last meal has left the small intestine (where it was absorbed into the blood stream), and hormones switch the body to ketosis. In a ketogenic state our bodies break down body fat (triglycerides) for energy. This state is called ketosis because when the triglycerides break down to fatty acids and glycerol, they produce ketone bodies.
Dr. Richard Veech of the National Institutes of Health says, “…ketosis is a normal physiologic state. I would argue it is the normal state of man.” The 8-Hour Diet just extends the nightly fast from 12 to 18 hours, 3 days a week.
David Mendoza, an early and frequent low-carb Type 2 diabetic blogger, offered a similar “weight-loss tip.” He said that whenever his weight drifted above “target” (he describes his current weight as “low-normal,” which sounds skeletal to me), he skips dinner that day. He said he has only had to do that 9 times in the last 6 months.Of course, anyone who follows Intermittent Fasting (IF) knows it has come a long way since “The 8-hour Diet” book in January 2013. If you’re not familiar with my favorite book, Google Dr. Jason Fung’s, “The Obesity Code.