High Fructose Corn Syrup- Obesity

By Bonnie Jenkins, Advanced Natural Medicine

What could be better on a sizzling summer day than an icy cold drink? The taller the better! But before you reach for that glass of soda or bottle of ice tea, you might be surprised to find out that these drinks do more than simply slake your thirst. They just might be making you fat.

The villain is high fructose corn syrup (HFCS), a sweetener used in everything from breakfast cereals to ketchup. But the biggest source of this sugar alternative can be found in sodas, sweetened ice tea, lemonade and “juice” drinks.

Sweet Deception

Once upon a time, ready-made drinks and drink mixes were made with refined sugar (sucrose) – the same stuff found in sugar bowls across America. But all that changed in 1967 with the introduction of HFCS. This corn-based sweetener was considerably cheaper than sugar and dissolved more easily. It was also twice a sweet, so manufacturers could use less. As a result, the familiar white crystals gave way for an industry built on HFCS. It has become so prevalent in drinks that consumption has increased more than 1,000 percent since the 1970s.

While most of us would concede that guzzling down 62.6 pounds of HFCS each year – the average amount consumed by the typical American – isn’t the healthiest habit, we probably wouldn’t equate the risk with, say, smoking. But maybe we should.

Over the past three decades, researchers started to notice an interesting correlation. It seemed that the surge in obesity and Type II diabetes ran parallel with the surge in HFCS consumption. And, while the fact that this corn-based sweetener was packed with calories explained part of this trend, it didn’t solve the whole puzzle.

New research from the University of Cincinati, however, shows that HFCS may actually alter the body's metabolism in a way that prompts it to store body fat. The main culprit – soft drinks.

Corny Complications

In the study, the UC researchers fed mice one of four drinks: HFCS-sweetened water, a soft drink sweetened with table sugar, a diet soft drink or water. Overall, the mice were offered approximately the same number of calories through food and drink each day of the study. Surprisingly, the mice that drank the fructose-sweetened water gained significantly more body fat than the others, even though they didn’t eat as much as the other mice. In fact, the HFCS group gained a whopping 11 percent body fat compared to just eight percent for the mice drinking the sugar-sweetened soft drink. In other words, even though the HFCS mice didn’t consume as many calories as the other mice, they still gained more weight!

Earlier research shows why this phenomenon happens. According to a small clinical trial by the University of California, Davis, HFCS actually changes the way our metabolism works. In their study of 12 women, blood samples were taken every hour for 24 hours on two different days. On these days, all of the volunteers ate the same three meals. After each meal, the women drank a beverage that was sweetened with either glucose or fructose (the two forms of sugar).

The researchers discovered that when subjects drank fructose, their levels of insulin and leptin – two hormones that make us feel “full” – were lower than in the subjects who drank glucose. On the flip side, levels of ghrelin, the hormone that makes us feel hungry, was measurably higher. More seriously, compared to the women who drank glucose, the fructose group experienced a prolonged spike in their plasma triglycerides.

But the real “AHA!” moment came when they ran the same experiment on animals. Fructose consumption contributed to insulin resistance, impaired glucose tolerance and high blood pressure, leading the UCD researchers to conclude that a high intake of HFCS may increase body weight and encourage insulin resistance, both of which are risk factors for type 2 diabetes.

The reason is that the body digests and absorbs glucose and fructose differently. Unlike simple table sugar, large amounts of fructose provide a relatively unregulated source of fuel for the liver to convert to fat and cholesterol. And since most of the fructose in our diet is consumed in liquid form, this negative metabolic effect is significantly magnified. Making matters worse, fructose, unlike glucose, doesn’t stimulate insulin secretion or enhance leptin production. As a result, HFCS is much more likely to be converted into fat.

One Last Thing ...

Last year, the American Journal of Clinical Nutrition published a study that compared how many refined carbohydrates Americans consumed between 1909 and 1997 to the prevalence of Type II diabetes. The researchers specifically looked at HFCS and concluded that the steadily increasing intake of this particular refined carbohydrate ran parallel with decreasing intakes of fiber and the upward trend in the number of Type II diabetes cases.

So here’s the bottom line: An occasional soda won't lead to obesity or Type II diabetes. It also won’t send you’re triglyceride levels on a permanent upward spiral. But when that weekly or monthly Coke becomes a constant habit, it can create huge health problems. And it’s particularly dangerous for children.

If you want a healthy way to quench your thirst, pour yourself a nice cool glass of purified water. Sipping green or herbal teas are also a wonderful way to beat the summer heat. And fruit juices – in moderation – not only hydrate, they can add valuable nutrients to your diet.

This Just In ...

Feeding your brain may be as easy as topping your morning cereal with blueberries, having steamed spinach with your dinner or boosting a smoothie with a teaspoon of Spirulina – an super-nutritious blue-green algae found in many “green” drinks. According to recent research, a diet rich in these three foods just might ward off two threats to your brains: senility and the loss of mobility caused by a stroke.

During the study, which appeared in Experimental Neurology, researchers from the National Institute on Drug Abuse fed rats one of three different anti-stroke diets or a control diet. One diet was high in spinach, one in blueberries and one in spirulina. At the end of the study, all of the rats eating the anti-stroke diets suffered less severe strokes than those in the control group. Their movement was much less affected and they lost fewer brain cells.

That's great news for rats. But can this simple fix translate to humans? Researchers suggest the answer is yes. It seems that rats and humans suffer comparable brain and motor damage during a stroke, which is why researchers suspect that the diets will work for humans. In both, strokes generate a flood of free radicals. But, because these three foods are extremely high in the antioxidants that neutralize free radicals, they excel at reducing stroke damage.

Earlier research by Tufts University found that these foods also reduced the oxidative damage that occurs in the brain as we age – which could reduce the risk of age-related memory loss, cognition and senility.

Fortunately, getting these protective benefits is easy. Just load up on blueberries and spinach – they’re delicious as well as healthful. And spirulina supplements and drink mixes are readily available. Bon appetit!

***

References:

Bray GA, Nielsen SJ, Popkin BM. “Consumption of high-fructose corn syrup in beverages may play a role in the epidemic of obesity.” American Journal of Clinical Nutrrition. 2004;79:537-543.

Elliott SS, Keim NL, Stern JS, et al. “Fructose, weight gain, and the insulin resistance syndrome.” American Journal of Clinical Nutrition. 2002;76:911-922.

Galli RL; Shukitt-Hale B; Youdim KA, et al. “Fruit polyphenolics and brain aging: nutritional interventions targeting age-related neuronal and behavioral deficits.” Annals of the New York Academy of Science. 2002;959:128-132.

Gross LS, Li L, Ford ES, et al. “Increased consumption of refined carbohydrates and the epidemic of type 2 diabetes in the United States: an ecologic assessment.” American Journal of Clinical Nutrition. 2004;79:774-779.

Wang Y, Chang CF, Chou J, et al. “Dietary supplementation with blueberries, spinach, or spirulina reduces ischemic brain damage.” Experimental Neurology. 2005; 193:75-84.

Warner J. “Fructose may alter metabolism to add body fat.” WebMD. 29 July 2005.