Fat Chance: The bitter truth about sugar. Dr. Lustig Robert
vacations put together (with interest).
Seat 7: The Federal Government
Our government is extraordinarily conflicted about where it should stand on the obesity pandemic. In 2003, former U.S. surgeon general Richard Carmona stated that obesity was an issue of national security, a stance that current surgeon general Regina Benjamin has upheld (despite the fact that she herself is obese) and one to which the U.S. Army has signed on. The public health branches of the government tell us that we eat too much and exercise too little. Mrs. Obama’s Let’s Move! campaign centers on the idea that childhood obesity can be battled by planting school vegetable gardens, encouraging kids to get out and exercise, and remaking the School Nutrition Act. All necessary, but not sufficient.
The U.S. government does everything it can to keep food cheap (see chapter 16). The USDA has chosen not to accept any responsibility for its role in the obesity pandemic, continuing to market our Western diet around the world. The Farm Bill (see chapter 21) maintains food subsidies to keep farmers employed and growing more crops. The growers make their profits on volume. The food processors make big markups and pass them along to the consumer. And the USDA subsidizes food entitlement programs to the poor, such as the Supplemental Nutrition Assistance Program (SNAP, formerly known as food stamps) and the Women, Infants, and Children nutrition program (or WIC, which supplies low-income infants and their mothers with food and health care), to keep them alive and complacent. Until 2007, WIC bowed to the pressure of food lobbyists. The foodstuffs provided were largely unhealthy, and included white bread and high-sugar juices.
The “Food Pyramid,” the federal nutrition guide released in 1974 (see figure 2.2a) and revised every five years, cultimating with “MyPyramid” in 2005, was never based on science. Indeed it was top and bottom heavy—hardly a pyramid. In response to calls for revision from many in the medical community, the Food Pyramid was deep-sixed in 2011. “MyPyramid” has now morphed into “MyPlate” (see figure 2.2b). The most recent guidance from the Dietary Guidelines Advisory Committee (DGAC), released in 2010, says that obesity is a problem (shocker) so we should all eat less fat, sugar, and salt. We’re all supposed to eat more fruits and vegetables, and less of everything else. This is stating the obvious. Don’t we already know this? Eat less? How? If we could eat less, there wouldn’t be an obesity pandemic. But we can’t.
Fig. 2.2a. The Ancient Pyramids. The traditional USDA Food Pyramid, circa 2005, which advised us to eat more grains and less fat and sugar. Alongside it, what Americans actually ate—more like an hourglass than a pyramid.
Fig. 2.2b. The Modern Merry-Go-Round. Under pressure from consumer groups and in response to the emerging science, the Pyramid was relegated to ancient history, and MyPlate was adopted by the USDA in 2011. MyPlate advises us to eat approximately half a plate of vegetables or fruits, one quarter fiber-containing starch such as brown rice, and one quarter protein, preferably low-fat. It’s too early to tell if this change will have any effect on American eating habits.
Each of the stakeholders in the obesity pandemic is singing the same tune: “Your obesity is your personal responsibility, it’s your fault, and you’ve failed.” And all these accusations are a variation on a theme based on one unflappable dogma: a calorie is a calorie.
Calories Don’t Count If…
The clues are all around us as to what’s really happened. It’s time to look at where those extra calories went, because it is in these data that we will find the answer to the obesity dilemma.
There are three problems with “a calorie is a calorie.”
First, there is no way anyone could actually burn off the calories supplied by our current food supply. A chocolate chip cookie has the equivalent calories of twenty minutes of jogging, and working off a Big Mac would require four hours of biking. But, wait! Olympic swimmer Michael Phelps eats 12,000 calories a day and burns them off, right? If this were the case for all of us, diet and exercise should work—you’d burn more than you ate and lose weight (see chapter 13). And diet drugs should work—you take the drug, eat or absorb less, and lose the pounds. Except the meds don’t deliver on their promises. They work for a brief period, and then patients reach a plateau in weight loss (see chapter 4).2 Why? Do the patients stop taking the pills? No. So why do the medications stop working? The answer: because the body is smarter than the brain is. Energy expenditure is reduced to meet the decreased energy intake. So a calorie is not really a calorie, because your caloric output is controlled by your body and is dependent on the quantity and the quality of the calories ingested.
Second, if a calorie is a calorie, then all fats would be the same because they’d each release 9.0 calories per gram of energy when burned. But they’re not all the same. There are good fats (which have valuable properties, such as being anti-inflammatory) and bad fats (which can cause heart disease and fatty liver disease; see chapter 10). Likewise, all proteins and amino acids should be the same, since they release 4.1 calories per gram of energy when burned. Except that we have high-quality protein (such as egg protein), which may reduce appetite, and we have low-quality protein (hamburger meat), which is full of branched-chain amino acids (see chapter 9), which has been associated with insulin resistance and metabolic syndrome.3 Finally, all carbohydrates should be the same, since they also release 4.1 calories per gram of energy when burned. But they’re not. A closer look at the specific breakdown of the carbohydrate data reveals something interesting. There are two classes of carbohydrate: starch and sugar. Starch is made up of glucose only, which is not very sweet and which every cell in the body can use for energy. Although there are several other “sugars” (glucose, galactose, maltose, and lactose), when I talk about sugar here (and in the rest of this book), I am talking about the “sweet” stuff, sucrose and high-fructose corn syrup, which both contain the molecule fructose. Fructose is very sweet and is inevitably metabolized to fat (see chapter 11). It is the primary (although not the sole) villain, the Darth Vader of the Empire, beckoning you to the dark side in this sordid tale.
The third problem with “a calorie is a calorie” is illustrated by the U.S. secretary of health and human services Tommy Thompson’s admonishment in 2004 that we’re “eating too damn much,” would suggest that we’re eating more of everything. But we’re not eating more of everything. We’re eating more of some things and less of others. And it is in those “some things” that we will find our answer to the obesity pandemic. The U.S. Department of Agriculture keeps track of nutrient disappearance. These data show that total consumption of protein and fat remained relatively constant as the obesity pandemic accelerated. Yet, due to the “low-fat” directives in the 1980s of the AMA, AHA, and USDA, the intake of fat declined as a percentage of total calories (from 40 percent to 30 percent). Protein intake remained relatively constant at 15 percent. But if total calories increased, yet the total consumption of fat was unchanged, that means something had to go up. Examination of the carbohydrate data provides the answer. As a percentage of total caloric intake, the intake of carbohydrates increased from 40 percent to 55 percent.4 While it’s true we are eating more of both classes of carbohydrate (starch and sugar), our total starch intake has risen from just 49 to 51 percent of calories. Yet our fructose intake has increased from 8 percent to 12 percent to, in some cases (especially among children), 15 percent of total calories. So it stands to reason that what we’re eating more of is sugar, specifically fructose. Our consumption of fructose has doubled in the past