Andrew Siegel Blog #119
Nature is ever so clever—look at our human species—brilliantly evolved and adapted not only to survive, but also to thrive on this planet, breathing the air in the atmosphere, drinking the water and eating the bounty from the soils of the fertile earth.
Whenever clever nature provides us with a nutrient that is potentially unhealthy, it protects us by limiting our access to that nutrient. Take, for example, sugar—also known as sucrose or, alternatively, 50% glucose/50% fructose—clearly unhealthy and a key contributor to the obesity epidemic. The major sources are sugar cane and sugar beets. If you ever tried to extract the sugar out of a sugar cane or sugar beet plant you would quickly find that they are fibrous and unyielding. If you want to derive calories from them, it requires great effort and you will likely end up quite frustrated. It’s not unlike chewing on a stick of bamboo and trying to suck the sugar out—at best we will only get a few calories out of the whole endeavor and probably burn more calories than taken in with the effort.
Because of the collective intelligence of mankind, we are now easily able to remove the protective fiber matrix of the sugar cane or sugar beet and process the sugar into a pure, refined and powdery product. This enables unrestricted access to the sugar and allows many “naked” calories to be easily consumed in a short time period. That is NOT the way nature intended, but humankind has prevailed over nature. Processing has allowed us to cheat nature by refining sugar, permitting consumption in immoderate and unhealthy amounts, contrary to nature’s design. However, it is very difficult to beat nature in the long run, and though mankind may have won this battle, we are losing the war, because the consequences of excessive sugar consumption are potentially dire and grave.
Most humans love—if not crave—the taste of sugar. It activates pleasure pathways in our brain that reinforce the desire for its continued consumption and, in some of us, it behaves like addictive substances. Even if one is extremely disciplined and rarely opens a packet or cube of sugar to sweeten their ice tea, chances are they nonetheless are consuming way too much sugar. The typical American diet adds 25 or so teaspoons of sugar to our daily consumption. This includes sugar from sugar cane and sugar beet sources as well as from the highly processed high fructose corn syrup (HFCS). In one month, this inadvertent cumulative sugar consumption is equivalent to approximately 4 extra days of eating!
Sucrose—a.k.a. table sugar—is a combination of glucose and fructose. All sugars are not the same. After consuming glucose, it is absorbed by the small intestine and used as fuel by our cells, aided by the hormone insulin. Any glucose that does not need to be used for immediate fuel is stored in the form of glycogen in our muscles and liver. Fructose behaves differently than glucose. Insulin does not have an effect on fructose and after absorption it goes straight to our livers where it is mostly converted to fat. Fructose does not cause the same amount of satiety as glucose does. Too much fructose leads to increased visceral fat and high blood lipid levels.
Fructose is the predominant sugar in many fruits, hence the term fructose. How do we explain the apparent paradox between fructose being a “bad” sugar, yet fructose being the main sugar in fruit, which is good for us? One difference between the fructose contained within fruit as opposed to that within a bottle of soda is that fruit fructose is natural and not created in a chemistry lab (i.e., high fructose corn syrup). Additionally, the concentration of fructose in fruit is significantly less than that contained within the soft drink. Furthermore, the fructose in beverages is a source of “empty” calories—essentially liquid candy—as they do not contain health-promoting ingredients present in fruit including fiber, anti-oxidants, vitamins, minerals and other phyto-nutrients. Because of the fiber content of the apple, the sugars are slowly absorbed whereas the “naked” sugars in beverage form are rapidly absorbed, providing a “load” of fructose to the liver. More than being just empty calories, fructose is a source of poisonous calories that promote obesity—think of fructose as fat.
Let’s do the math comparing an apple to a bottle of soda: An average-sized apple has about 80 calories: this includes 20 grams of sugar consisting of 4 grams of sucrose (equivalent to 2 grams fructose and 2 grams glucose), 5 grams of glucose, and 11 grams of fructose, for a total of 13 grams of fructose. A 20-ounce bottle of soda has about 240 calories: this includes 60 grams of sugar all from HFCS (55% fructose / 45% glucose) for a total of about 35 grams of fructose.
High fructose corn syrup is a gooey, liquefied sweetener that is abundant in processed foods and beverages. The typical American consumes an astonishing 50-100 pounds of HFCS per year! The derivation of HFCS is as follows: Corn is milled to cornstarch, a powdery substance that is then processed into corn syrup. Corn syrup consists primarily of glucose. Through a complex chemical process, the glucose in the corn syrup is converted to fructose. HFCS results from the mixing of this fructose back in with glucose in varying percentages to achieve the desired sweetness: 55% fructose/45% glucose ratio of HFCS is used to sweeten soft drinks; 42% fructose/58% glucose ratio of HFCS is used in baked processed foods.
The processed food industry is quite enamored with HFCS for a number of reasons. First, it is cheaper than sugar because of huge corn subsidies and sugar tariffs. Second, the liquid syrup lends itself to ready transportation in enormous storage vats within 18-wheelers, similar to how gasoline is hauled. Third, fructose is incredibly sweet and does not crystallize or turn grainy when cold, as sugar can do. Fourth, because HFCS is very soluble and retains moisture, it makes for softer and moister processed baked goods. Fifth, it acts as a preservative that extends the shelf life of processed foods and helps to prevent freezer burn. Finally, HFCS is a key ingredient in many processed junk foods, which are addictive and promote cravings and continued consumption.
There is a good reason why HFCS is so demonized: while HFCS may help “preserve” processed foods, it does not help “preserve” us! In fact, a diet high in HFCS will help accelerate our demise. To reiterate an important fact: fructose is metabolized very differently from glucose. Every cell in our bodies can metabolize glucose, but it is primarily the liver that metabolizes fructose. Fructose does not stimulate insulin release as does glucose, nor does it stimulate leptin (our satiety hormone). Fructose, more readily than glucose, replenishes liver glycogen, and once the liver is saturated with glycogen, triglycerides (fats) are made and stored. So, too much HFCS and we end up with a fatty liver and body. The bottom line is that HFCS ingestion pushes our metabolism towards fat production and fat storage, potentially leading to obesity, diabetes, elevated cholesterol, high blood pressure and cardiovascular disease. HFCS should be thought of as a toxin, in precisely the same way that tobacco is dangerous to our health. Unfortunately, sugar in the little packets that we use to sweeten our frappuccinos is really no better.
Bottom Line Tips: High fructose corn syrup and sugar are NOT our “friends,” so:
· Don’t drink too many calories or sugars if possible: minimize sodas, sweetened ice tea, lemonade, fruit juices, sports drinks, etc. Water or seltzer with lemon, lime or other fruit is so much healthier. Go for the real fruit instead of the juice. Easy on the alcohol because it is all carbs. Even milk has sugar in the form of lactose, (consisting of glucose and galactose, about 11-12 grams/cup.
· Avoid processed yogurts that are laden with excessive amounts of sugar because of the processed fruit on the bottom. You are much better off adding fresh fruit to plain yogurt.
· Try to avoid snacking on candy, cookies, energy bars, etc., and instead munch on nuts, fiber-rich fruits and vegetables and whole grains, like popcorn.
· Eat healthy cereals instead of those that are sugar-laden: steel-cut oats are so much healthier than Fruit Loops.
· Beware of “alternative” sweeteners—brown sugar, honey, molasses, maple syrup are all more-or-less the same.
· Read labels carefully since about 75% of packaged foods have sweeteners some that would surprise you, including sauces, salad dressings, breads, etc.
· Bottom line: use sugar and alternative sweeteners in moderation
Coming soon: Artificial sweeteners
Andrew Siegel, M.D.
Author of Promiscuous Eating: Understanding and Ending Our Self-Destructive Relationship with Food: www.promiscuouseating.com
Available on Amazon in Kindle edition
Author of: Male Pelvic Fitness: Optimizing Sexual and Urinary Health, in press and will be available in e-book and paperback formats in the Autumn 2013.
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Tags: brown sugar, diabetes, fructose, glucose, glycogen, high fructose corn syrup, honey, insulin, lactose, maple syrup, molasses, nature, obesity, processing, refined sugar, sucrose, sugar, sugar beets, sugar cane