LITHIUM CHLORIDE is a salt of lithium that has been used experimentally as an immunomodulator. INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY ENVIRONMENTAL HEALTH CRITERIA 54 AMMONIA This report contains the collective views of an international group of. PYRIDOXINE HYDROCHLORIDE
The bitter truth about fructose alarmism. Dr. Robert Lustig, professor of pediatrics at the University of California at San Francisco, is the star of the video above. While he presents some material that’s scientifically sound, he also makes enough errors to warrant a healthy dose of criticism. There’s a ton of material he goes over, so instead of writing a multi- chapter opus, I’ll discuss the aspects that I feel are the most relevant and interesting. Bravo, Doc. Lustig’s delivery is clear, confident, charismatic, and engaging overall. I’m sure many would think that his style is annoyingly smug and preachy, but I find it entertaining. This is a good thing, since the video is about 9. Amidst the folly that prompted this post, he offers a few good observations. First off, he makes a valid point that the public health movement against dietary fat that started in the early 1. The climb in obesity to epidemic proportions over the last 3. It was also accurate of him to cite the significant increase in overall caloric consumption over this same time period. Furthermore, he shows an interesting progression of Coca- Cola’s 6. Lustig acknowledges the First Law of Thermodynamics as it applies to changes in bodyweight. He attacks the vague expression that “a calorie is a calorie” by pointing out that different nutrients impart different physiological effects and have different roles within the body. His concluding recommendations included kicking out liquid calories except milk, which is generally a good strategy for children. But what does he say that’s so misleading? Let’s take a look. Boooo, Doc. While Lustig correctly points out that the nation’s overall caloric consumption has increased, he proceeds to blame carbohydrates as being the primary constituent. The thing is, he uses data spanning from 1. Survey data is far from the gold standard of evidence, but if you’re gonna cite it, you might as well go with something more recent that includes adults. Here’s the latest from the USDA Economic Research Service (ERS), which tracked the percent of total daily calories of the range of food groups from 1. The actual spreadsheet of the following figures can be downloaded here, click on the “Percents” tab at the bottom (note that these figures are updated regularly by the ERS, so the version you download may be different from what’s reported here) . By 2. 00. 7 this hiked up to 2. Taking a hard look at the data above, it appears that the rise in obesity is due in large part to an increase in caloric intake in general, rather than an increase in added sugars in particular. Lustig insufficiently addresses the . According to the research, it’s possible that over the last couple of decades, we’ve become more sedentary. King and colleagues recently compared the physical activity data in the National Health & Nutrition Examination Survey (NHANES) from 1. NHANES data from 2. From a personal observation standpoint, that figure seems conservative (internet surfing for hours after your desk job shift, anyone?). It’s safe to say that all 6. It’s also safe to say that all this finger- pointing at carbohydrate is just as silly as the finger- pointing toward fat in the ’8. Lustig takes the scapegoating of carbohydrate up a notch by singling out fructose. Perhaps the most passionate point he makes throughout the lecture is that fructose is a poison. Well, that’s just what we need in this day and age – obsessive alarmism over a single macronutrient subtype rather than an aerial view of the bigger picture. Fructose is evil, context be damned. So, is fructose really the poison it’s painted to be? The answer is not an absolute yes or no; the evilness of fructose depends completely on dosage and context. A recurrent error in Lustig’s lecture is his omission of specifying the dosage and context of his claims. A point he hammers throughout his talk is that unlike glucose, fructose does not elicit an insulin (& leptin) response, and thus does not blunt appetite. This is why fructose supposedly leads to overeating and obesity. Hold on a second. You’d have to go out of your way to obtain fructose without the accompanying glucose. Sucrose is half fructose and half glucose. High- fructose corn syrup (HFCS) is nearly identical to sucrose in structure and function. Here’s the point I’m getting at: contrary to Lustig’s contentions, both of these compounds have substantial research showing not just their ability to elicit an insulin response, but also their suppressive effect on appetite . In studies directly comparing the effect of fructose and glucose preloads on subsequent food intake, one showed no difference . A recent review of the literature on fructose’s effect on satiety found no compelling case for the idea that fructose is less satiating than glucose, or that HFCS is less satiating than sucrose . So much for Lustig’s repeated assertion that fructose and fructose- containing sugars increase subsequent food intake. I suppose it’s easier to sensationalize claims based on rodent data. In the single human study I’m aware of that linked fructose to a greater next- day appetite in a subset of the subjects, 3. This amounts to 1. Is it really that groundbreaking to think that polishing off a half- dozen soft drinks per day is not a good idea? Demonizing fructose without mentioning the dose- dependent nature of its effects is intellectually dishonest. Like anything else, fructose consumed in gross chronic excess can lead to problems, while moderate amounts are neutral, and in some cases beneficial . This is because people have a tendency to think in either- or terms that strictly involve extremes. I’ll quote an elegant review by independent researcher John White that echoes my thoughts . Thus, studies using extreme carbohydrate diets may be useful for probing biochemical pathways, but they have no relevance to the human diet or to current consumption. Atkins, Japan, & alcohol – oh my! One of Lustig’s opening assertions is that The Atkins diet and the Japanese diet share one thing in common: the absence of fructose. This is flat- out false because it implies that the Japanese don’t eat fruit. On the contrary, bananas, grapefruits, Mandarin oranges, apples, grapes, watermelons, pears, persimmons, peaches, and strawberries are significant staples of the Japanese diet . Lustig’s claim also implies that the Japanese do not consume desserts or sauces that contain added sucrose. This is false as well. Another oversimplification Lustig makes is that fructose is “ethanol without the buzz,” and that fructose is toxic to the liver. This once again helps me illustrate my point that even in the case of alcoholic beverages, their risk or benefit to health is dose- dependent. Just like his extremist treatment of fructose, Lustig bases his case on the effect of chronic isolated ethanol consumption in large doses. It’s easy to examine ethanol out of its normal context within beverages such as wine, because then you can conveniently ignore the evidence indicating its potential health benefits when consumed in moderation . To a degree, this is a valid claim. However, in building this stance, he uses sugarcane to illustrate just how fiber- dominant natural sources of fructose are, and this is the exception rather than the rule. He claimed that, “Wherever there’s fructose in nature, there’s way more fiber.” That statement is far from universally true. Drawing a few common examples from the major fruits consumed in Japan, a midsize banana contains roughly 2. A midsize apple contains 2. Two cups of strawberries contains 2. I would add that fiber is only one of the numerous phytochemicals in fruit that impart health benefits. Thus, it’s not quite as simple as saying that fructose is evil, but once you take it with fiber, you’ve conquered the Dark Side. Summing up. I have a great deal of respect for Lustig’s professional accomplishments, and I share his concern for the nation’s penchant for sitting around and overconsuming food and beverages of all sorts. However, I disagree (as does the bulk of the research) with his myopic, militant focus on fructose avoidance. He’s missing the forest while barking up a single tree. So, what’s the upper safe limit of fructose per day (all sources considered)? Again, this depends on a number of variables, not the least of which are an individual’s physical activity level and lean body mass. Currently in the literature is a liberal camp reporting that fructose intakes up to 9. Hb. A(1c), and no significant effects are seen for fasting triacylglycerol or body weight with intakes up to 1. The conservative camp suggests that the safe range is much less than this; roughly 2. The big picture solution is in managing total caloric balance with a predominance of minimally refined foods and sufficient physical activity. Pointing the finger at fructose while dismissing dosage and context is like saying that exercise should be avoided because it makes you fat and injured by spiking your appetite and hurting your joints. Note: for those with little tolerance for reading through over 4. Loss- Adjusted Food Availability Data. Adherence to healthy lifestyle habits in US adults, 1. Ju; 1. 22(6): 5. 28- 3. High- fructose corn syrup, energy intake, and appetite regulation. Dec; 8. 8(6): 1. 73. S- 1. 74. 4S. No differences in satiety or energy intake after high- fructose corn syrup, sucrose, or milk preloads. Dec; 8. 6(6): 1. 58. Sugars and satiety: does the type of sweetener make a difference? Jul; 8. 6(1): 1. 16- 2. Effects of glucose- to- fructose ratios in solutions on subjective satiety, food intake, and satiety hormones in young men. Nov; 8. 6(5): 1. 35. Effects of fructose and glucose preloads on subsequent food intake. Metabolic effects of fructose and glucose: implications for food intake. Apr; 4. 7(4): 6. 83–9. Rodin J. Comparative effects of fructose, aspartame, glucose and water preloads on calorie and macronutrient intake. Am J Clin Nutr 1. Effects of pure sugar versus mixed starch fructose loads on food intake. Appetite 1. 99. 1; 1.
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