A few months ago a very well read fellow blogger, Beth Mazur, commented on a post of mine. She said she shared my view that as lay bloggers we play a valuable intermediary role as generalists, or “foxes,” in a world of specialists, “the hedgehogs.” She was referring to a recent essay by Harry Rutter in The Lancet (sorry, log-in required). Rutter was referring to a popular 1953 essay, “The Hedgehog and the Fox,” by British philosopher Isaiah Berlin. It’s a good read.
In a separate post on her own blog, Weight Maven, Beth introduced me to Lucas Tafur with a piece he wrote on the “Old Friends Hypothesis,” referring to gut flora. Gut flora is an emerging and interesting area of nutrition research. It seems even my favorite MD, Kurt Harris, is telling us “to look at other things” besides “NAD’s.” Harris was referring to Neolithic Agents of Disease, his construct and original prescription of dietary constituents to avoid: wheat, fructose and Omega 6 fatty acids. His lengthy comment on Paleo Hacks, here, which Beth brought to my attention, was pretty cryptic, though. Harris’s thinking is apparently “evolving,” but that is one of the aspects I like best about his approach to dietary science.
Lucas Tafur is also an interesting story. Before he created the Luca Tafur site, his blog was called Ketogenic Nutrition. It is inactive now but still “up.” It provided me with a nostalgic look back at what proved for me to be a very effective way to lose weight (170 pounds). Tafur, whose bio is on both websites, quotes one of the world’s leading experts on ketone bodies, Dr. Richard L. Veech of the National Institutes of Health: "Doctors are scared of ketosis. They're always worried about diabetic ketoacidosis. But ketosis is a normal physiologic state. I would argue it is the normal state of man.” Put into context, in the continuum of our day-to-day existence, we’re either in a fed or a fasting state. The fed state begins with eating and continues until the food has been digested and absorbed. The fasting state then begins and continues until we eat again. When fasting, the body is said to be in ketosis.
When we are in a fed state, we derive our energy largely from glucose. This is called a glycogenic state. When we are in a fasting state, the body derives its energy from our fat stores, both from the liver and from our adipose (fat) tissue, which breaks down by lipolysis. Who can doubt that it has been that way for thousands of generations? We were hunters and gatherers, not grazers. That is the way we were “designed.” For just a few generations, we have gone astray, with disastrous consequences. Of course, what has happened in the last few generations is not an evolutionary adaption; it is but an aberration. It is also a completely reversible change once we come to see and accept what “we” (complicit with our agricultural/industrial enterprise and the associated “public health” and media establishments) have done to ourselves. We can return to a fed and then fasting Way of Eating in which ketosis is one of “the normal states of man.”
The scenario: We hunted, we ate and we were satisfied. Think of the lion lying around after consuming a kill. After a while he became hungry and hunted again while he continued to get his energy from fat stores. The body shifted from being a “sugar burner” to a “fat burner.” As Dr. Veech said: “the normal state of man.” The fed state is when the body uses carbs to make glucose for energy. The fasting state is when the body uses fat to make ketone bodies for energy. But, as Tafur then points out, ketosis can “either be triggered by fasting or by diet.” Therein lies the key for us today.
The rest of this column is excerpted from Lucas Tafur’s Ketogenic Nutrition website, where he provides footnotes as well: “Fasting ketosis develops after a few days of fasting, when liver glycogen stores are depleted. The body, as an acquired evolutionary mechanism, shifts from a glucose-based metabolism to a fat-based one.” “Studies have shown that the adaptive response to fasting is regulated not by energy restrictions per se, but by carbohydrate restriction. This is because the rate limiting enzyme of ketogenesis…is controlled by insulin levels.”
“The body’s main energy store is adipose tissue. Fat is more calorie-dense, meaning that it yields more energy per gram than glucose. Fat is the body’s preferred fuel, ketones being a “super fuel” that can be used by some tissues that haven’t evolved to use free fatty acids (FFA) such as the brain. Ketone bodies help the body spare amino acids by reducing the need for glucose. This way muscle mass is maintained…. Without ketosis, body protein stores would be cannibalized…. “
“The body stores fat primarily as saturated fat because it is metabolically more efficient than glucose and produces less toxic residues when metabolized. Exogenous glucose is the first substrate to be used because it is toxic to the body. It produces metabolic disregulation caused by hyperglycemia, which triggers an inflammatory and autoimmune response. Ketosis represents the opposite scenario; it protects the body during a life threatening situation like starvation.” (end)
So, Tafur gives a fine description of fasting ketosis, but what is dietary ketosis? It is the subject of the next column.
© Dan Brown 7/1/12
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