Clearly, the incessant anti-fat propaganda has not worked in reducing the obesity problem in the U.S. This propaganda, of course, was based on the assumption that eating fat makes us fat. Seems simple enough, of course, but only in a vacuum in which we ignore complex metabolic mechanisms (not to mention the simple fact that fat makes us feel full, so if we actually listen to what our bodies are telling us, we eat less when we eat a fatty meal).
More and more evidence has trickled out that sugar, which in excess is metabolized to become fat (especially in the liver), is the real obesity culprit. The pediatric obesity expert Dr. Robert Lustig’s video on the topic went viral, and the mainstream media has picked up the idea.
Certainly the circumstantial evidence is strong, because in the rush to demonize fat, guess what was added to processed foods to replace it? Yep – usually, sugar, and a lot more of it. For example, sometime try reading the label of the “healthy” nonfat Dannon yogurt you are feeding your kids all the time.
There is unfortunately a lot of misinformation in this area, and we also have to remember that scientists haven’t necessarily discovered a new magic diet rule that will save us all from metabolic syndrome and obesity-related health problems. The anti-high-fructose corn syrup movement, although valid to a point — there is evidence that HFCS does indeed lead more to obesity than sucrose (cane sugar) — has unfortunately obscured the real problem, by implying that cane sugar is just fine. You can watch the video for the details as to why this assumption is wrong, but although HFCS may be worse for health than an equal amount of sucrose, the real problem is that high-fructose corn syrup became a much cheaper product than cane sugar (a lot due to corn subsidies) in the last few decades. That’s when all those fountain soft drinks at McDonald’s and the convenience stores got huge; the soda industry wanted to make it look like you were getting so much more for your money, when actually they were raking in huge amounts of money for all the Big Gulps, because the cost of soda production is minimal. And so people’s dietary intake of sugar via sodas and all kinds of processed foods that dropped in price went up – way up.
It is not clear why HFCS is so much worse than sucrose, and more studies are needed to confirm this finding. Although fructose is indeed the primary culprit in metabolic changes that lead to obesity and its suite of health problems, sucrose breaks down into fructose and glucose, and you get only marginally more fructose from the same amount of HFCS as sucrose – 55% vs. 50%. But there is another major difference:
…as a result of the manufacturing process for high-fructose corn syrup, the fructose molecules in the sweetener are free and unbound, ready for absorption and utilization. In contrast, every fructose molecule in sucrose that comes from cane sugar or beet sugar is bound to a corresponding glucose molecule and must go through an extra metabolic step before it can be utilized.
But none of this changes the fact that American humans consume orders of magnitude more sugar, in any form, than pre-industrial humans. Want to know how much sugar is in a typical can of soda? There are about 40 grams, which doesn’t mean a lot to people, until they understand that in one teaspoon there is about 5 grams of sugar. This means from one twelve-ounce can of pop, you are consuming 8 teaspoons, or nearly 3 TABLEspoons of sugar. Our bodies simply were not designed to deal with that amount of sugar blasting us at once, and all our liver can do with it is turn most of it into fat. In contrast, when we eat an apple, we may consume 20 grams of mainly fructose, but it seems the effects of fruit sugars are somewhat mitigated by other nutrients in the apple, such as magnesium. Plants have all kinds of compounds whose metabolic effects we don’t yet understand, or have limited understanding of, which is why the intensive marketing of multivitamins is simplistic and at worst, harmful.
But for those who remain unconvinced, here’s another smoking gun: researchers are finding that excess blood sugar teams up with the dreaded LDL cholesterol to create a previously unknown type of extra-killer-cholesterol. This helps explain why diabetics are at higher risk for heart attacks and strokes. Adding the sugar groups to the cholesterol molecule turns out to make them really, really, sticky, even compared to other cholesterol, and so clog up your arteries that much faster. (It is much more likely to happen in diabetics because their problems with sugar metabolism means they have more sugars floating around in their blood than non-diabetics.)
The difficulty with all of this is not only that metabolism is highly complex, but that one of the things that makes it so is the variation among people both in genetics and environment. Everyone is different, and that makes it a challenge to prove that a single person changing his or her diet will see obvious effects.
But the collective data are accumulating all the time that on a population level, it is the obscene amounts of sugar we eat that are killing us, not so much the somewhat high fat intake we have. It’s actually a lot easier to demonize fat, and take it out of processed foods — especially given a populace that is rebelling against artificial ingredients, including man-made sweeteners whose effects we surely don’t fully understand, but which we just as surely aren’t designed to process. So here we are. What should we do about it?
Photo by Warnichtmehrfrei (Own work) [CC-BY-SA-3.0 (www.creativecommons.org/licenses/by-sa/3.0) or GFDL (www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons