They're twisting the numbers...If enough people LC, average Fat intake will go up. In fact, average fat intake was already increasing. Fat intake reached an all time low in the 1980s [< 90g,] and rebounded slightly in the 90s and early 20th century [to around 100g.] For the first half of the century, it was about 139g. But, just because there's enough people to effect the average percentage of fat, does NOT mean there's enough people to effect the Obesity rate.

The number of folks who the daily intake percentages are based on remains realtively steady, so any change in even a small number will effect the percentages of the larger population. OTOH, more and more people become Overweight and Obese every year, so even if hundreds or thousands of LCers lose their excess weight, it won't show up as a decrease in Obesity rates. For that to happen, we'd have to slow or halt the rate of new cases of Obesity.

BTW, its a myth that we are eating more than before. Current Caloric intake is about the same as it was in the 60s/70s, and slightly lower in some cases. The differences are in composition [Fat and Protein intake decreased, and Carbs increased to fill the void] and physical activity [we don't get as much.] A common trick used by LFers is to compare present intakes to those of the 1980s or late 1970s...when Fat and Caloric Intakes were at an all time low. Then, they claim we are getting fatter because we're eating more Calories and Fat. They never mention that our parents ate 38g more Fat and the just as many Calories as we did, but didn't have such high rates of Obesity, Heart Disease, Diabetes, and Cancer. If fat really caused these maldies, the incidence of each should've decreased from the 70s-80s, and increased slightly during the 90s. Instead, we saw a steady increase for the entire period, even when Fat Intake was decreasing, rates of these maladies were INCREASING. The only things that increased during the entire period were consumption of Carbohydrates [especially refined] and Hydrogenated Oils [which replaced Animal Fats.]

Another myth is that we're eating less Fruits and Vegetables. From the 1970s to the 1990s...intake of both Fruits and Veggies increased. Unfortunately, the increase was mostly Juice and Potatoes. But, according to the LFers, those count. Currently, potato consumption is declining...But, as of a few years ago the intakes were still much higher than they were a few decades ago. I haven't found many stats [other than the Potatoes] newer than 1999. So, I can't say how consumption of other Fruits and veggies have changed.

In fact, over the last few decades consumption of Frozen Potatoes doubled, while consumption of fresh potatoes declined slightly. Recently, consumption of both has declined slightly. But, it would take years or even decades of such declines for frozen potato consumption and total potato consumption to return to Pre-70s levels. I can't say whether or not Grain consumption is decreasing. But, Grain is another case of a food that has gotten a free ride for the last 3 decades. In some cases (Corn and Rice) consumption went up 100-200% over the last 3 decades. Short of 90% of the population giving up Grains tomorrow, t would take years of steady declines to undo such an increase.