As part of our new On the Spot web feature, Dr. Robert Lustig, professor of clinical pediatrics and director of the Weight Assessment for Teen and Child Health (WATCH), agreed to answer your questions.
Below we've published some of the questions you've asked of Dr. Lustig, along with his responses.
Please remember that we may not be able to answer all questions or address all comments. Nor can we or the participating faculty member offer specific medical advice. For medical advice, you should always contact your personal physician.
Q. What steps should our elected representatives take to address the problem of toxic food manufacturing processes?
Really good question. Unfortunately, no good answers. I personally believe that food should have nutritional standards (not just a nutrition facts box), which should be monitored by the FDA, and foods should be pulled that don't meet those standards. But you won't find too many politicians willing to take that on. A simpler idea would be to ban high-fructose corn syrup. This of course will raise the price of sugar, but that may not be such a bad thing. It will get sugar out of many of our foods and our schools, which will help this problem immensely. Obesity has to be treated as a disease, not as a behavior, so physicians can get reimbursed, and patients can have access to therapy. Politicians can help there. Also, physician, school, and parent education is a must. Right now, pediatricians don't know what to tell mothers about infant and child feeding, and don't have the time. Those are starts.
Q. Physical education and nutrition classes (where students learned to cook with healthy ingredients) have been largely abandoned in many American schools. Would restoring and valuing them have any impact on the obesity factors you describe?
Of course this would help. One of my main mantras is "eat your carbohydrate with fiber." This is because fiber lowers the insulin response through three separate mechanisms: 1) speeding the food through the gut to get the satiety signal sooner; 2) reducing the rate of sugar absorption from the gut into the bloodstream; and 3) helping intestinal bacteria digest triglycerides into short-chain fatty acids, which dampen the insulin response. But no one likes fiber (because we've been deprived of it by Big Food), and no one wants to wait for high-fiber foods to cook through (e.g. brown rice takes 45 minutes to cook, while white rice takes 20 minutes). So cooking wisely (more fiber, less sugar, less saturated fat) can certainly help.
Sugar and Sweeteners
Q. Dr. Lustig, I heard you on KQED and was quite impressed by the information regarding sugar. I am wondering, are more "natural" or less processed forms of sugar such as maple syrup or honey a more healthy way to sweeten things? Or are they equivalent to white sugar?
White sugar is sucrose, which is half glucose and half fructose (fruit sugar). Although glucose generates an insulin response (and therefore promotes deposition of energy into fat and weight gain right after a meal), fructose is the really bad actor. Fructose is like "alcohol without the buzz." It poisons your liver, and makes it insulin resistant; therefore, your pancreas makes even more insulin to make the liver work properly. This forces energy into fat all the time. Maple syrup and honey are just glucose. While caloric and insulin generating (therefore obesogenic), they don't have fructose to damage the liver and promote insulin resistance. So, although not perfect, they would be better than sucrose.
Q. You've been quoted as saying that juice, even "100% natural" is no better than soda, because they contain the same carbohydrates. Would you recommend drinking diet soda, then, as an alternative to either juice or regular soda? What about coffee or tea, sweetened with sugar (I mean here brewed and then sweetened, as opposed to bottled teas and coffee drinks, which I assume are as bad as soda and juice)?
Diet sodas don't have calories, although some sweeteners can still generate a small insulin response. So, on balance, diet sodas are better than sugared ones, if you like percolating chemicals through your bloodstream. Sweetened coffees or teas are no better than soda, as they still generate an insulin response, and they are sweetened with sucrose (which is half fructose, which is bad for your liver). My question to you is, why do you need sweet drinks at all? What's wrong with water? The human race had no sweet drinks until 1915, when Coca-Cola went national. Until then, we had water and milk, and we did just fine, thank you. Juice was invented in the 1950s. We didn't have obesity in the first half of the 20th century. But we have seen both soft drinks and juice sales rise astronomically, at the same time the obesity epidemic started to build. There is some suggestion that the earlier you expose an infant to "sweet", the more likely they will crave it later. We need to get America off its "sweet habit". Water has everything you need, and nothing you don't. And it's cheap.
Diet and Hormones
Q. Dear Dr.Lustig: I have a question regarding diet and hormone balance. I am a 33 year-old female and, unfortunately, I have facial hair that is equivalent to a man's beard. I have consulted my Primary Care Physician and he has ruled out an ovarian cyst. He has stated that it is genetic. In my early 20s, I consulted an endocrinologist who said my testosterone levels were 20 points higher than normal. Could something in my diet be causing this hormonal imbalance? Is there anything I can do to remedy this situation without taking birth control pills or other drugs? If I do need to take a drug, which would have the least side effects? Thanks for your time.
Without knowing your specific history, physical, and lab tests, it is impossible for me to accurately diagnose your condition. It certainly sounds like polycystic ovarian syndrome (which may or may not have ovarian cysts). There is a "thin" PCO, and a "fat" PCO, and they are not the same. But they do seem to share insulin resistance as an inciting factor. Insulin resistance at the ovary causes the production of too much testosterone and not enough estrogen. There are two treatments for PCO. One is metformin, which improves insulin resistance and lowers insulin levels, and the other is birth control pills, which effectively puts the ovary to "sleep", so it won't make more testosterone. You should discuss your condition with your doctor.
Childhood Obesity Caused by "Toxic Environment" of Western Diets, Study Says
UCSF News Release, August 11, 2006
"Toxic Diets" Fuel Child Obesity
BBC News, August 19, 2006
High-Cal, Low-Fiber Diets Driving Kids to Obesity
, August 22, 2006
On Food: Our Eating Habits Are as Processed as Our Foods
, August 23, 2006