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An apple a day keeps the doctor away. Remember the good ol’ days when maxims like this were all you needed to live a healthy and long life? Now, the public is bombarded with confusing messages about their health every day. The latest example is 60 Minutes report on “Toxic Sugar”. I had several people ask me about this because they wanted to know my opinion – so here it is: just because Dr. Sanjay Gupta says something does not mean it is true…or any one scientific study for that matter. Dr. Richard Lustig has been in the limelight recently, as his idea to tax sugar was the basis for my Boston Sugar Party post. Let’s look at the “facts” Lustig and others presented in the report:
“Sugar is toxic.” Sugar itself is not toxic. You actually need sugar to live. Your brain needs 6 grams of glucose (a type of sugar) per hour to work properly. In addition, when your muscles and other tissues cannot take up glucose to create energy, as in the case of type 1 diabetics, you will starve to death. Think of it this way: you need water to live, but if you drink massive amounts of water, you will die within hours. If you drink massive amounts of sugary drinks, your pancreas will pump out more insulin to remove the sugar from the bloodstream, and after a while you might become obese, then you may become insulin resistant, some people might become diabetic, and only then will you cause major organ damage. Considering the time it takes to kill you after overconsumption, water is more toxic than sugar.
“There is no foodstuff on the planet that has fructose that is poisonous.” Lustig was trying to make the point that humans WANT to eat fructose because of evolution and we instinctively know it’s safe to eat. I’d like to see his analysis of fructose content on holly berries, sweet peas, and the other poisonous foodstuffs listed by a poison control center in Philadelphia.
“We were born this way.” He is obviously a Lady Gaga fan, promoting her song, “Born This Way”…ok, that’s untrue, just trying to add some levity here…he just states that we are born to love fructose. Yes, we may enjoy eating fructose (it has the highest sweetness out of all of the natural sugars), but I still don’t buy the claim that we are prone to it because of evolution and poisonous things.
“Fructose causes heart disease and stroke.” This is new research coming out of the Dr. Kimber Stanhope lab, and any new hypothesis must be thoroughly tested before it becomes consensus. The amount of fructose consumed is astronomically high, at 25% of daily calories. This is not too unusual for scientific studies trying to determine effects from diets, but not many people are actually drinking this many calories every day without any type of exercise. She states there is are increases in LDL cholesterol and “other risk factors” for cardiovascular disease. No mention of whether these increases are statistically significant or if sugar is ACTUALLY “just as bad for their hearts as their fatty cheeseburgers.”
“[In the 1970’s] a government commission mandated that we lower fat consumption to try to reduce heart disease.” This is true, governmental attempts to lower fatty foods did not make us healthier. Some foods were processed down until the fat was removed, but all the sugar, salt, and calories were still there, and usually some chemicals added in to replace the fat. However, there was no real regulation of fatty foods and many ‘low-fat’ items on the shelf were always considered ‘diet foods’ that people did not eat consistently. People still gravitate toward high-fat foods. Sugar alone did not increase American adult obesity to 36%. You can order a Double Quarter Pounder with Cheese from McDonald’s which has 740 calories, more than half of those calories coming from the 42 grams of fat. But it only has 9 grams of sugar! It won’t make you fat! Again, this is just not true. (Just to be fair to other fast food chains, an Extra-Crispy Chicken Breast at KFC will set you back 510 calories, 290 of those come from the 33 grams of fat…but only 1 gram of sugar!) You need a well-rounded diet of protein, carbohydrate, and fat for your body to function properly. Telling people that sugar is toxic creates the next “scare” that Lustig said happened with fat 40 years ago, and obesity rates will keep increasing.
“If you limit sugar, it decreases the chances of developing cancer.” Dr. Lewis Cantley’s example that cancer cells have insulin receptors and will therefore take up excess glucose from the bloodstream and grow into tumors was probably the most shocking to me. Insulin receptors bind insulin (which is secreted from your pancreas and into the bloodstream after every meal) and if cells have certain glucose transporters, insulin ‘tells’ those transporters to move from inside the cell to the cell surface. This results in increased glucose entry into the cell. Many cells in your body have insulin receptors such as muscle, liver, fat, and brain. Muscle (skeletal and heart) and fat cells have the glucose transporters that are ‘activated’ by insulin. There is no data that I am aware of which claims cancer cells can take up more glucose than any of the other cells in your body. Also, insulin signaling (what happens inside the cell after insulin binds the insulin receptor), once activated, is eventually downregulated by a negative feedback system. Insulin cannot just sit on an insulin receptor and hang out, causing cancer cells to keep sucking up the sugar, or blue dots, as the schematic on the television show would like you to believe.
“Every cell in our body needs glucose to survive, but the problem is, these cancer cells also use it to grow.” Once again ALL CELLS that have the insulin receptor use glucose to grow. Period.
“Sugar is much more addictive than we thought early on.” These scientists seem very careful with their wording. Dr. Eric Stice showed that dopamine was released in Gupta’s brain when he drank some soda. Activation of taste receptors on your tongue cause dopamine to be released in the brain, no matter what the food. If a person likes spinach, the same dopamine receptors will light up in MRI brainscans, especially if the person is hungry at the time. Dopamine regulates feeding behavior, and not just for sugar. Maybe sugar can be addictive, but so can so many other things (including suntanning, as I mentioned in my Tanners Anonymous post). We can’t possibly regulate every choice people make.
As a scientist, I believe the scare tactics that Lustig is using are not within the ‘unwritten rule’ of putting the science first in research. I am all for new ideas, but a scientist cannot go on national television to state untested claims as fact and contribute positively to the field of science. You’re probably thinking, “he must be a first-hand expert to make these claims on television, right?” During my scan of his last 27 papers published in peer-reviewed journals since 2009, I calculated only five that were original work coming directly from his lab (where he was last author and they were not review articles). These five papers had nothing to do with ‘toxic sugar’ and its effects on the human body. The most recent concerns growth hormone deficiency in children after radiation treatment, and the other four are about the efficacy of lifestyle intervention (behavioral) programs in obese children. In the other 22 papers, he either contributed to another lab’s work, or they were review or opinion articles on sugar, fast food, and obesity. Something about this seems fishy to me, and it isn’t Friday. You can’t be an objective scientist and (what seems to me) to be striving for fame at the same time. He wrote an article about ‘toxic sugar’ in the journal Nature a couple months ago, and that’s when the mainstream media started to interview him and publish articles on his opinions. There are 5 other articles in subsequent issues of Nature that refute his claims. Here are some quotes from these articles:
Our meta-analyses of controlled feeding trials indicate a net metabolic benefit, with no harmful effects, from fructose at a level of intake obtainable from fruit (Nature. 2012 Feb 23;482(7386):470).
To describe sugar as “toxic” is extreme, as is its ludicrous comparison with alcohol…Nutritionist Jennie Brand-Miller of the University of Sydney is not alone in her disgust that you published this opinion piece (The Australian, 4 February 2012). The Dietitians Association of Australia believes that it is simplistic and unhelpful to blame sugar alone for the obesity crisis. Alan Barclay of the Australian Diabetes Council notes in the same article in The Australian that sugar consumption in Australia has dropped by 23% since 1980. But he adds that during that time, the number of overweight or obese people has doubled, while diabetes has tripled (Nature. 2012 Feb 23;482(7386):470).
Overconsumption of foods that have a high glycaemic index (that trigger a rapid and sharp increase in blood glucose), such as wheat, potatoes and certain types of rice, also contributes to obesity and diabetes. Emphasis on sugar alone is therefore too narrow a basis for devising policies to curb these problems (Nature. 2012 Feb 23;482(7386):471).
Rather than demonizing sugar, the authors would have better served public health with recommendations to manage a balanced diet with exercise (Nature. 2012 Feb 23;482(7386):471).
The Food and Agriculture Organization of the United Nations, the US Food and Nutrition Board, and the European Food Standards Authority have all considered the issues now revisited by Lustig et al. and find no reliable evidence that typical sugar consumption contributes to any disease apart from dental caries. Without evidence that reducing sugar consumption would improve public health, Lustig and colleagues’ policy proposals are irrelevant. Scientific controversies should be settled by consideration of all the available evidence, not of a seemingly biased selection (Nature. 2012 Mar 8;483(7388):158).
I appreciate the attention the ‘Western Diet’ is getting (the diet high in refined grains, sugar, fat, and red meat), as there are major problems with it that lead to obesity and diabetes, but presenting hypotheses as fact to scare the public is not the way to do it. This is how fad diets are created and may cause people more harm than good. Educating the public with real information and making it easier for them to make good dietary choices is the best way to battle the bulge. I say, it probably is best if you don’t drink sugary drinks everyday, but having one every once in a while will not kill you. And enjoy that apple.