Wednesday, August 09, 2006

Freaktrition: Seth Roberts' Shangri-La Diet

Seth Roberts, an autodidact experimenter who uses himself for one-sample studies into the effects of acne treatments and diets, has announced a diet so fantastic he calls it "Shangri-La".

Roberts claims to demonstrate, through research and the results of his own experiments with his diet, that the body has a genetic "set point" for body fat storage, and that traditional dieting cannot lower this. The only way to lose fat and keep it off, he says, is by tricking your body into thinking it's not time to stock up on fats by taking your calories in tasteless and even mildly nauseating ways: spoonsful of olive oil, and lots of water with fructose added.

At least one rave reviewer swears by Roberts' ideas:
It is the cheapest diet I’ve ever been on. Five dollars worth of extra light (not extra virgin) olive oil from Costco or SAM’S CLUB lasts you six months. I’ve probably eaten less than half the food I would have otherwise eaten in that time...

I’m healthier, I’m happier, and I’m grateful for the diet and for the book. I’m back to walking four or five miles a day as I did when I was first married, I’m enjoying judo again, and I sleep much more soundly and need less sleep.
This diet was featured in one of the Freakonomics authors' columns in the NY Times, which are much more interesting than their agonizingly repetitious book.

Roberts' paper "What Makes Food Fattening?" is a published survey of a half-century of diet research on animals and humans. It reports the following conclusions:
  1. Eat new foods. No food with a new flavor is fattening, the theory implies.
  2. Vary the flavor of foods eaten repeatedly. If products came with optional flavoring packets and consumers added varying amounts of the flavorings, this would produce variation in flavor...
  3. Consume calories with no flavor associations. Ingestion of calories with no flavor should lower the set point, the theory implies. The fructose-water results suggest that ingestion of a small fraction of one’s daily calorie intake this way may substantially reduce the set point. Flavorless vegetable oils (vegetable oils, such as olive oil, from which all flavor molecules have been removed) are a possible source of calories without taste.
He also addresses the famous dilemma of why East Asians, particularly Japanese people, are so seldom obese:
Japanese food has weaker flavors than other cuisines. As one cookbook
says, “Most Japanese cuisine is seasoned only lightly; strong spices are never used” (Suzuki, 1994, p. 8). Weaker flavors lead to weaker flavor-calorie associations, as discussed earlier (Figure 2). In addition, at the time of the data shown in Figure 7, Japanese cuisine was also low in high-GI foods, such as bread and potatoes. According to Barer-Stein (1980, p. 335), “the staples of the traditional Japanese diet are rice, fish and seafood, vegetables and tea.” This too should have reduced the strength of flavor-calorie associations, as discussed earlier. When Japanese emigrate to the United States and adopt an American diet, they eventually weigh as much as other Americans (Curb & Marcus, 1991), which supports this explanation. (p. 36)
In one study Roberts describes, lab rats grew fat on supermarket food but not on more tasteless lab
To make rats fat quickly, Sclafani and Springer (1976) placed supermarket food, namely “chocolate chip cookies, salami, cheese, bananas, marshmallow, milk chocolate, and peanut butter” (Sclafani & Springer, 1976, p. 462), in their home cages. Lab chow remained available. The rats could eat as much as desired. After eight weeks, they had gained over three times as much weight than rats not given supermarket food – far more weight gain than a high-fat diet produced under the same conditions (Sclafani & Springer, 1976)...

Why was supermarket food much more fattening than lab chow? As stated
earlier, supermarket food competes for shelf space. Foods that produce a strong flavor-calorie association will be preferred, other things equal (Sclafani, 1991). Supermarket foods are selected for this property, in the sense that foods with more of it are more likely to be bought; and foods that are not bought are no longer stocked. Lab chow does not undergo the same selection process. Rats are not given a choice between different versions of lab chow and how much tasty rats find a particular version has little effect on what is bought or made.
So far, little surprise. But here is what is promising, if it's true:
The supermarket food took one to two weeks to cause weight gain, which argues that learning was involved (Ramirez, 1990a). This is roughly the length of time required for flavor-calorie learning to become strong (e. g., Bolles, Hayward & Crandall, 1981).
Other explanations: Perhaps the supermarket food was more palatable than the lab chow. However, the delay in the start of this effect argues against this explanation (Ramirez, 1990a). Ramirez, Tordoff and Friedman (1989, p. 163) noted that “evidence for this hypothesis [that palatable food causes obesity] is particularly weak.”
It's hard to know what's more suspect: Roberts' claims of his own incredible results, or his enlisting medical research to assert that his messianic diet is supported by science. Dr. Atkins' confident summaries of human physiology, after all, have been called less than accurate by many doctors.

If Roberts is right, though, how would we know? This is a problem in the current system of strong peer-review in science. Those doing research outside of universities and not publishing in mainstream journals are so often con men or quacks that many promising thinkers among their ranks get painted with the same brush as charlatans.

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Anonymous Anonymous on Wed Aug 09, 10:53:00 PM:
Japanese eat a lot more than "Japanese food," and on the whole it's spiced along the lines of any other nation's food. For instance, curry rice is really common in "home cooking." It's not super spicy Indian curry, but it's as spicy as any American beef stew is. Fried foods are eaten with lots of gloppy "sauce" or "tonkatsu sauce" on it, a Worcestershire style, very sweet sauce. Fish is often salted when bought (for instance, the various mackerels and salmon/salmon-trouts), and soy sauce is used heavily. Even bland tofu is eaten with soy sauce, grated ginger, and chives on top. A lot of "Chinese" food is eaten in Japan, which is spiced with tobanjan, a sort of chile pepper-miso paste from China, as well as garlic, ginger. oyster sauce, etc. Food like sushi and sashimi is not eaten on a daily basis by Japanese.
Blogger seth roberts on Sun Aug 27, 08:42:00 AM:
"If Roberts is right, how would we know?" That's a good question. How about we begin to know by looking at what happens when people try the diet?
Blogger Ben on Mon Aug 28, 10:51:00 AM:
Absolutely. Just because most people who promise fantastic diet changes with less effort than the old excercise-and-eat-better method method are essentially conmen doesn't mean Roberts is. Any word on studies being done on the diet?