While Lustig correctly points out that the nation’s overall caloric consumption has increased, he proceeds to blame carbohydrates as being the primary constituent. The thing is, he uses data spanning from 1989-1995 on children aged 2-17. Survey data is far from the gold standard of evidence, but if you’re gonna cite it, you might as well go with something more recent that includes adults.
Here’s the latest from the USDA Economic Research Service (ERS), which tracked the percent of total daily calories of the range of food groups from 1970-2007. The actual spreadsheet of the following figures can be downloaded here, click on the “Percents” tab at the bottom (note that these figures are updated regularly by the ERS, so the version you download may be different from what’s reported here) [1]:
Meats, eggs, and nut kcals decreased 4%.
Dairy kcals decreased 3%.
Percentage of fruit kcals stayed the same.
Percentage of vegetable kcals stayed the same.
Flour and cereal product kcals increased 3%.
Added fat kcals are up 7%,
Added sugars kcals decreased 1%
Total energy intake in 1970 averaged 2172 kcal. By 2007 this hiked up to 2775 kcal, a 603 kcal increase.
Taking a hard look at the data above, it appears that the rise in obesity is due in large part to an increase in caloric intake in general, rather than an increase in added sugars in particular.
Lustig insufficiently addresses the ‘energy out’ side of the equation. According to the research, it’s possible that over the last couple of decades, we’ve become more sedentary. King and colleagues recently compared the physical activity data in the National Health & Nutrition Examination Survey (NHANES) from 1988-1994 with the NHANES data from 2001-2006, and found a 10% decrease [2]. From a personal observation standpoint, that figure seems conservative (internet surfing for hours after your desk job shift, anyone?). It’s safe to say that all 603 extra daily calories have been landing in the nation’s collective adipose depot.
It’s also safe to say that all this finger-pointing at carbohydrate is just as silly as the finger-pointing toward fat in the ’80′s. Lustig takes the scapegoating of carbohydrate up a notch by singling out fructose. Perhaps the most passionate point he makes throughout the lecture is that fructose is a poison. Well, that’s just what we need in this day and age – obsessive alarmism over a single macronutrient subtype rather than an aerial view of the bigger picture.
