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Alarming New Side Effects of Eating Too Much Sugar, Says Study

New research has linked overconsumption of sugar with several manic disorders.
FACT CHECKED BY Faye Brennan
Sad and lonely woman feeling depressed

By now, it's largely taken as gospel that overconsumption of sugar is one of the most prevalent and insidious causes of weight gain. Thanks in part to the lobbying of the food industry, sugar consumption rose by 25 percent between 1970 and 2000, in almost exact parallel with the increase in high-fructose corn syrup production and obesity, according to a review by the Union of Concerned Scientists. By 2013, a review of literature in PLOS Medicine had analyzed eighteen scientific conclusions drawn from systematic reviews of studies on the link between sugar-sweetened beverage consumption and weight gain or obesity. Among reviews conducted by scientists without any reported conflict of interest, ten out of twelve found that sodas and other sugary beverages could be a risk factor for weight gain. Overconsumption of sugar has also been linked to health conditions that range from cancer risk to feelings of depression.

But a new study published in the journal Evolution and Human Behavior just shed light on some alarming new side effects attached to the overconsumption of sugary foods. The research from the University of Colorado Anschutz Medical Campus suggests that sugar could play a key role in driving several manic behaviors, including aggressive behavior, bipolar disorder, and attention deficient hyperactivity syndrome (ADHD).

"We present evidence that fructose, by lowering energy in cells, triggers a foraging response similar to what occurs in starvation," notes lead study author Richard Johnson, MD, professor at the University of Colorado School of Medicine on the CU Anschutz Medical Campus.

That foraging response, the researchers write, could play a role in driving "risk-taking, impulsivity, novelty seeking, rapid decision making, and aggressiveness to aid the securing of food as a survival response. Overactivation of this process from excess sugar intake may cause impulsive behavior that could range from ADHD to bipolar disorder or even aggression."

The researchers argue that the drive to consume more sugar is inherent in our brains as an evolutionary "pathway" that ensure our survival. But given all of the available sugar options at our fingertips, this "survival pathway" is now on "overdrive." That inherent response could contribute to the aforementioned disorders—as well as manic depression.

"Chronic stimulation of the pathway could lead to desensitization of hedonic responses and induce depression," the study concludes. "A hyperactive foraging response driven by high glycemic carbohydrates and sugars may contribute to affective disorders."

The University of Colorado's Johnson notes, "We do not blame aggressive behavior on sugar, but rather note that it may be one contributor."

Consider this latest research yet another reason for cutting back on your sugar intake. To help you do so, we've compiled just a few of the foods you're eating that you had no idea were high in sugar, below. So read on, and for a more complete list of foods to avoid, don't miss this eye-opening list of the 30 Worst Grocery Foods With the Most Sugar.

1

Smoothies in a Bottle

Bottled fruit juice
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If you're buying your smoothie from the drink section at your local gas station, chances are, you're not exactly buying a fiber-rich drink filled with fresh and nutritious fruits. In fact, most bottled smoothies don't have any satiating macronutrients and don't use any real blended fruit. The smoothie manufacturers often use fruit juice concentrates and fruit purees to enhance their sweet sips, and those ingredients can be just as damaging as high fructose corn syrup, an additive that has been said to cause increased levels of bad cholesterol, weight gain, and belly fat accumulation. Here's the #1 smoothie trick to help you lose weight.

2

BBQ Sauce

Barbecue sauce
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Always check the label of any store-bought BBQ sauce, and beware of any brand that is promoting its "honey sweetness." Sweet Baby Ray's Honey Barbecue sauce, for instance, contains a whopping 15 grams of sugar in 2 tablespoons!

3

Cereal Bars

cereal bars
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They look so healthy, but so often, they're not. Not only are these bars typically lacking in satiating nutrients like fiber and protein, but certain brands will trick you into thinking they have a lot less sugar than they do (i.e. many packages contain two bars and not just one, but only list the sugar content of one).

4

Salad Dressings

salad in bowl with dressing poured over top
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Certain bottled salad dressings are well-known sugar bombs. If you're trying to stay healthy and lose weight, choosing a dressing that's marketed to be "fat-free" or "light" is the wrong move. In order to make up for the loss of flavor provided by fat, companies pack the bottles with chemicals, sodium, and—of course—sugar. So steer clear, and for more foods to avoid, see this list of The 100 Worst Foods on the Planet.

William Mayle
William Mayle is a UK-based writer who specializes in science, health, fitness, and other lifestyle topics. Read more
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