The first speaker at the low carb conference in SF recently was Gary Taubes:
The Quality of Calories.
Competing paradigms of obesity
pathogenesis, a historical perspective
The obesity rate has risen from 31 million people, or 15% of the population, in the early 1970s, to 111 million, or 34% in 2010. Diabetes rate has also risen dramatically, from 2% of the population, 4.2 million, in 1973 to 8%, or 21.1 million in 2010.
In addition, many metabolic diseases have also risen dramatically, such as stroke, heart disease, gall bladder disease, hypertension, ostioarthritis, fatty liver disease and cancer.
Why?
Taubes quotes the conventional wisdom, that the fundamental cause of obesity and overweight is an energy imbalance between calories consumed and calories expended.”
The World Health Organisation.
That is, an energy imbalance between energy in and energy out. Calories in exceed calories out.
The science of nutrition was born in 1866, and in the 1890s Atwater and Benedict show thermodynamics holds true for humans and pioneer the science of calorimetry.
Louis Newburgh’s revelation:
“All obese persons are alike in one fundamental respect—they literally overeat.”
Therefore....
Obesity is caused by either a “perverted appetite” (eating too much) or “lessened outflow of energy” (insufficient expenditure).
The conclusion was that it was all the obese person's fault, it all lay in the mind:
Ignorance,
Self-indulgence,
Gluttony,
Sloth.
Taubes then demolished the CICO hypothesis by asking the question, "how much energy imbalance is required to gain, for example, 20 pounds in ten years?"
That's 2 lbs per year.
I pound = 3,500 calories.
Thus 2x3500/365 = an average of 19.2 extra Cals per day. That's two peanuts, 3 almonds, 4 olives, or two gummy bears. So to lose that excess weight, just eat two gummy bears less per day?
Taubes called into question whether weight gain is really that fine tuned.
The average American is now 30 pounds heavier than in 1960 — an average weight gain of .53 pounds per year.
That's equivalent to us all eating an excess of half a gummy bear per day, if the CICO is to be believed.
Taubes then gave this quote, introducing the idea of a set point:
"There is no stranger phenomena than the maintenance of a constant body weight under marked variation in bodily activity and food consumption."
Eugene Du Bois, Basal Metabolism in
Health and Disease, 1936
Other flaws in the CICO theory he gave are:
Eating less doesn't work:
Weight loss achieved in trials of calorie-restricted diets is “so small as to be clinically insignificant.”
Cochrane Collaboration, 200
Likewise, exercising more doesn't work.
Do children at puberty grow taller because they have eaten more? And do girls at puberty grow more fat in the breasts because they have eaten more? Clearly something else is at work, increasing size.
Finally, Taubes dispensed with the CICO with the following analogy:
“The fundamental cause of wealth is a money imbalance between dollars earned and dollars spent.”
The World Economic Forum
He said he earns more than he spends, so why isn't he a billionaire?!
Taubes then moved on to the alternate hypothesis on obesity:
Obesity is a disorder of excess fat accumulation
(Not energy balance, not over-eating, not sedentary behavior)
Gluttony and sloth are compensatory effects.
The hormonal/regularity hypothesis:
“Like a malignant tumor or like the fetus, the uterus or the breasts of a pregnant woman, the abnormal lipophilic tissue seizes on foodstuffs, even in the case of undernutrition. It maintains its stock, and may increase it independent of the requirements of the organism. A sort of anarchy exists; the adipose tissue lives for itself and does not fit into the precisely regulated management of the whole organism… a lipomatous subject may die of starvation and still remain lipomatous.”
Bauer, Archives of Internal Medicine, 1941
Two important figures of this German/Austrian hypothesis, pre-World War II , were Gustav von Bergmann (1908), and Julius Bauer.
Their hypothesis was more or less accepted as fact, until it because a victim of World War Two. The war was a huge set back to the hormone approach to obesity.
"Looking at obesity without preconceived ideas, one would assume that the main trend of research should be directed toward an examination of abnormalities of the fat metabolism, since by definition excessive accumulation of fat is the underlying abnormality. It so happens that this is the area in which the least work has been done."
Hilde Bruch, The Importance of Overweight, 1957
But the CICO camp won the day.
A few held the hormone torch:
Insulin is “the principal regulator of fat metabolism.”
Rosalyn Yalow, Solomon Berson, 1965
Key points of fat cell regulation:
When insulin is secreted or chronically elevated, fat accumulates in the fat tissue.
When insulin levels drop, fat escapes from the fat tissue and the fat depots shrink.
We secrete insulin primarily in response to the carbohydrates in our diet.
“Carbohydrate is driving insulin is driving fat.”
George Cahill, 2005
Taubes then stated the alternative hypothesis to CICO:
Like any growth defect, obesity is a hormonal/regulatory disorder.
Like type 2 diabetes, it is fundamentally a disorder of insulin signaling -- hence, diabesity.
It is triggered by the carbohydrate content of the diet.
He then went on to criticise the food pyramid, with it's emphasis on grains (6-11) portions per day, as being a main reason for the increase in obesity.
Taubes contrasted two statements, both from the Textbook of Obesity, 2012:
“All diets that result in weight loss do so on one basis and one basis only: they reduce total calorie intake.”
And, same book, same year:
“All diets that result in weight loss do so on one basis and one basis only: they reduce circulating insulin (by restricting carbohydrates).”
No wonder so many are confused!
Ways to reduce insulin levels:
Calorie restriction (with carbohydrate restriction)
Carbohydrate restriction (without calorie restriction
— i.e., LCHF/Keto)
Intermittent Fasting
Fasting…
Taubes ended with several quotes showing the conventional wisdom through the 1960s.
"Farinaceous and vegetable foods are fattening, and saccharine matters are especially so… ”
Tanner, The Practice of Medicine, 1869
“Every woman knows that carbohydrates are fattening, this is a piece of common knowledge, which few nutritionists would dispute.”
British Journal of Nutrition, 1963
And advice to combat obesity:
Foods to be avoided:
-
Bread, and everything else made with flour…
-
Cereals, including breakfast cereals and milk puddings
-
Potatoes and all other white root vegetables
-
Foods containing much sugar
-
All sweets…
You can eat as much as you like of
the following foods:
-
Meat, fish, birds
-
All green vegetables
-
Eggs, dried or fresh
-
Cheese
-
Fruit…except bananas and grapes
Raymond Greene, The Practice of Endocrinology, 1951
This sounds like our diet, that AMA criticizes as a fad diet, yet was written in 1951!
To add my own personal note to verify everything Taubes says on the conventional wisdom before the 1970s:
I was brought up in Post World War Two Europe, when we couldn't get down from the table until we had eaten our meat and veggies; we had to have the cream from the top of the milk "because it was good for us"; parents of obese children were disapproved of for feeding them "too much bread and potatoes"; and children got pocket money on Saturdays to spend on candy, and that was it.
In other words, they had it right back then. In my eyes, the fad diet is the low fat one that came in long after I had grown up and been taught good eating habits. Too bad I was persuaded!
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