Fructose, the Low-Fat Fattener

April 7, 2012 Updated: October 1, 2015
Epoch Times Photo
Robert Lustig, M.D., has concluded that consuming products with high fructose corn syrup, especially in soft drinks, is the major cause of chronic illness and death. (Benjamin Chasteen/The Epoch Times)

Among the many battles now going on in the world is the battle of the bulge. However, the FDA, the USDA, and the AMA do not officially recognize the true enemy.

Robert Lustig, M.D., professor of clinical pediatrics in the Division of Endocrinology at U.C. San Francisco, has studied the metabolism of sugars and treated obese children. He concludes that high fructose corn syrup (HFCS), especially in sodas, is the major undercover agent causing chronic illness and death from the unborn to the elderly.

Dr. Lustig has made his findings public in a 90-minute video, “Sugar and Its Bitter Truths,” which is available on In the video, he demonstrates that fructose in the quantities that we imbibe, especially for the younger generation, is equivalent to poison.

Our bodies perceive HFCS and sucrose (cane or beet sugar) as two different substances, even though the Corn Refiners Association keeps saying that their molecules are the same—one fructose and one glucose.

Tell that to a liver cell or a digestive enzyme. HFCS is sent directly to the liver—the organ that takes care of toxic substances we ingest.

Before processed foods, sugar consumption was about 15 grams per day per person. In whole foods, the fruit and vegetable sugars are naturally packaged with fiber and micronutrients, both of which mitigate the bad effects of sugar.

Little by little, our consumption of refined sugar has increased over the years. Sugar is already bad. Too much sugar of any kind disposes one to weight gain, cancer, and diabetes. We were already being set up to become sugarholics when sugar was derationed after World War II.

With the advent of HFCS in the 1970s and the creation of HFCS from enzymes and cornstarch by the Japanese, the sweetener became cheaper, and corn growers were happy.

Below is a table showing the increase in the amount and proportion of sugar in everyone’s diet since the 1950s, according to Dr. Lustig’s video.

For adolescents, the figures are even more dramatic. In 2009, adolescents alone consumed 73 grams of sugar per day, or 12 percent of their daily calories. And 25 percent of adolescents consumed at least 15 percent of their calories from fructose—a huge amount.

The two different processes of sugar metabolism illustrate why one sugar is slightly better than the other and why fructose in HFCS, fruit juices, and baby formula is causing metabolic syndrome in kids as young as 6 months old.

Sucrose meets sucrase, an enzyme, in the small intestine, where the sucrose is transferred to the bloodstream. Sucrose is a double sugar composed of about half glucose and half fructose.

High sucrose levels in the blood tell the liver to notify the beta cells in the pancreas to secrete insulin, which enables glucose to be taken in by all the cells for energy production.

Some glucose is stored in the liver as glycogen for future energy, and some is stored as fat if it is not burned for energy. Leptin is called forth by insulin and informs the brain that one is no longer hungry.

Fructose is processed differently. It arrives at the liver intact, as the sucrase couldn’t deal with it. HFCS in soda is 55 percent fructose. The liver has an enzyme to process fructose, but it needs a phosphate that the liver gets from ATP, its source of energy made by mitochondria.

The result of this robbery—caused by the large volume of fructose—is the formation of uric acid and the elimination of an important enzyme that keeps blood pressure down. Uric acid is a waste product that predisposes one to gout.

As the process continues, various enzymes come into play, forming fat not only in the liver but also in organs and muscles. VLDL, the fat that lines the arteries, and triglycerides rise precipitously.

Although the liver is calling for insulin, and a large amount is sent over, the excess fatty acids formed in the liver go through a complex sequence that results in damage to the insulin-receptor sites, which causes insulin resistance.

Meanwhile, at the liver’s behest, the pancreas is pumping out insulin. This overproduction of insulin causes insulin resistance, turns off the receptors for leptin in the brain, and makes the victim unsatisfied and still hungry.

Having a soda before a meal won’t spoil one’s appetite because ghrelin, which is from the stomach and makes the sensation of hunger, will not be suppressed. The calories in the soda will not be registered by the body and will be turned into fat by the extra insulin.

This is Part 1 of a series on fructose. Read Part 2: A Cure for Addiction to Sweet Drinks.