Update, January 2020: Sugar addiction is no longer a metaphor.
The sugar that is added to processed food and beverages acts as a slow poison that disrupts normal liver functions in the same way that alcohol does. It leads to high blood pressure, heart disease, Type-2 diabetes, dyslipidemia, pancreatitis, liver disease, fetal insulin resistance, and, of course, obesity.
That’s the bad news from Dr. Robert Lustig, professor of pediatrics at the University of California, San Francisco, where he runs their obesity clinic for children. You can hear it straight from him in a 90-minute presentation that has been posted on YouTube.
The good news? All of this damage is 100% preventable. Here’s how:
- First, eliminate all soft drinks, sports drinks, fruit drinks, and other sugar-flavored beverages from your diet.
- Second, eliminate all commercially-processed food products, including “fast foods”, of course, because these are loaded with high-fructose corn syrup (HFCS) that slowly kills your liver, makes you fat, and eventually kills you.
To put it more simply: Forget all that complicated stuff about calories, low-fat diets, and good cholesterol. Just cut out the added sugar.
Your only source of sugar should be fruit, where it is mixed with a lot of fiber—essential to a healthy diet—and other important micro-nutrients.
In Dr. Lustig’s obesity clinic for kids, the patients
- drink only water and milk—no sugared liquids
- eat high-fiber carbohydrates (i.e., not fast-food carbs, which have little or no fiber)
- wait 20 minutes before eating a second portion
- and must “buy” video/computer time minute-for-minute with physical activity.
This program, if followed, is successful. I know: you are not surprised that eliminating junk food and exercising would lead to weight loss. Here’s what is surprising: in studies conducted at Lustig’s clinic, kids who gave up sugared liquids still lost weight, even if they ignored the other three rules. But kids who did the other three—ate high-fiber carbs, waited 20 minutes before taking a second portion, and exercised—failed to lose weight if they kept drinking sugared liquids.
Conclusion? Above all, it’s the sugar.
Here are some other highlights from Dr. Lustig’s presentation:
Obese babies
Worldwide, there is now an epidemic of obese 6-month-old babies. Why? Because they are being fed commercial formulas that are loaded with sugar—”milkshakes for babies.” Popular diet and exercise theories cannot explain obesity in 6-month-olds—only the sugar in baby formula can.
Fructose
High-fructose corn syrup (HFCS) was invented in Japan in 1966 and introduced to the American diet in 1975. Since then its use has exploded. Why? First, it costs half of what sucrose (table sugar) costs. Second, it is added to processed foods and soft drinks—and baby formula—to make them taste good.
Competing diets
The Adkins diet is all fat, no carbohydrates. The “Japanese” diet is all carbohydrates, no fat. If followed correctly, they both work. Why? Because they both eliminate fructose. On the other hand, if you follow either of them but keep your sugar consumption constant, neither of these diets work. In other words: it’s the sugar!
Why fiber is important
Over-production of insulin—one of the effects of fructose in the liver—leads to Type-2 diabetes. According to Lustig, fiber in the diet slows the speed at which food is absorbed in the intestines, and inhibits the absorption of some free fatty acids, both of which reduces the insulin response. Pre-industrial people consumed 100-300 grams of fiber each day. Today the average American consumes just 12 grams of fiber per day. Fiber is removed from processed foods and fast foods because it takes too long to cook, takes too long to eat, and won’t store well.
Why exercise is important
The common notion is that we exercise to “burn calories”, but Lustig ridicules the idea that we can overeat sugary foods and then burn those calories off with exercise. Just one cookie, he says, would require 20 minutes of running. So we simply cannot exercise enough to compensate for a sugar-soaked diet.
Instead, here are the benefits of exercise. First, it improves skeletal muscle insulin sensitivity—i.e., like fiber, it helps prevent Type-2 diabetes. Second, it reduces stress, which in turn reduces our appetite because stress makes us feel hungry. Third, it increases our metabolic rate, which again improves insulin function in the liver.
Why everyone is fatter than they used to be
Americans of all ages are eating more than they did 30 years ago. Why? Because sugar in the liver screws up the normal processes that make us feel full when we have eaten. We eat, but we are still hungry. The biochemical system in our bodies that tells us when we have had enough to eat has been disrupted: it doesn’t work anymore. And this is a direct result of sugar consumption. And it’s not only in America. All over the world, wherever soft drinks and fast food are replacing traditional diets, we see the same effects: obesity, diabetes, heart disease, etc.
Why Coke makes us fat
What is in Coke? Caffeine and salt. Caffeine is a stimulant and diuretic, i.e., it makes us urinate. There are 55mg of salt in a can of Coke—the equivalent of drinking a pizza. So if you take in salt and lose free water, you become thirsty, and want to drink more. Why is there so much sugar in Coke? To hide the taste of the salt. (This is like sweet-and-sour pork in a Chinese restaurant: the sugar disguises the saltiness of the soy sauce.) “New Coke” has more salt and more caffeine, and therefore makes people even thirstier than old Coke. So they drink more and more, and their sugar consumption skyrockets. No wonder kids who drink soda pop get fat. In just five years, 1989-94, soft drink intake by American children increased 41% and fruit drink intake increased 35%.
Sports drinks
Gatorade was invented in the 1970s. It works very well for elite athletes who exert themselves to the point that their glycogen is depleted. The original formula, however, tasted terrible, so when the Pepsi-Cola company purchased Gatorade in 1992, they added loads of HFCS to it to make it taste good. Then they began marketing it to kids whose glycogen levels were just fine. Result? A generation of fat kids sucking down sports drinks.
I urge you to watch Dr. Lustig’s presentation. I used to take the view that a little sugar—or even a good whack, once in a while—was harmless, but Lustig has convinced me otherwise. If you don’t have time to watch the video, however, that’s okay: just stop consuming added sugar. Now.
UPDATE: June 1, 2011
Dr. Lustig’s thesis seems to be borne out by this news report from Shanghai, China:
Shanghai schoolchildren getting very fat very fast: survey
UPDATE: February 2014
Another link: 25 reasons to stop eating sugar.
UPDATE: April 2014
More evidence against sugar (including the high amounts found in canned and dried fruit, and fruit juice) in this article from the Guardian: http://www.theguardian.com/uk-news/2014/mar/31/refined-sugar-real-villain .
UPDATE: June 2014
Vox interview with Robert Lustig: http://www.vox.com/2014/6/6/5786974/the-war-on-sugar
“Our Year of No Sugar: One Family’s Grand Adventure”: http://www.everydayhealth.com/columns/my-health-story/year-of-no-sugar-one-family-grand-adventure/
UPDATE: February 2015
Sugar is 8 times more addictive than cocaine; it can take six weeks to kick the habit and overcome the craving for sugar. And why is pizza so addictive? —it’s all the added sugar in the tomato sauce.
http://abc13.com/health/study-sugar-is-as-addictive-as-cocaine/533979/
Plus: activist group in the UK calls for ban on sales of energy drinks for kids under 16.
http://www.bbc.com/news/health-31623771
UPDATE: March 2015
This excellent summary of the case against sugar is written by The Iowa Clinic, “the largest physician-owned multi-specialty group in central Iowa.”
UPDATE: April 2015
How to Break Your Sugar Addiction in Ten Days (from Dr. Mark Hyman and the Cleveland Clinic).