The Truth About Junk Food

By Grace McCalmon, Refinery29

Soda, potato chips, nachos, candy, doughnuts, curly fries, and (my personal favorite) late-night cheesy bread from a certain national pizza chain that shall remain nameless - what do all these things have in common? They're tasty and delicious delights, obviously. But, they also all fall under the classification of junk food - otherwise defined as: Any food that's high in calories, low in nutrients, and generally tastes so good you wonder why you can't eat it for breakfast, lunch and dinner. Of course, you don't because these foods are bad for you. But, what does "bad" actually mean?

We decided to find out. Using Time Magazine's list of the Top 10 Iconic Junk Foods as a guide, we compared ingredients and investigated the three common denominators: fructose, fat, and food dyes. And, what we found has us reconsidering what we grab when we need an afternoon snack. Click ahead to get the whole story on what you eat.

Related: How Healthy Is Your Diet, Really?

Fructose
Fructose or more specifically, high fructose corn syrup (HFCS), came under attack after a 2004 paper linked HFCS to America's soaring obesity rates. For the past ten years, a battle has raged between those that decry HFCS as the "Devil's candy" and those that argue HFC is no worse than table sugar. Either way you google it, there's heaps of evidence supporting both sides of the argument, so here are the biological facts:

Regular cane sugar (sucrose) is made of two sugar molecules: glucose and fructose - bound together in equal amounts. HFCS also consists of glucose and fructose in 55-45 fructose to glucose ratio, and in an unbound form. Since there is there is no chemical bond between them, no digestion is required, so HFCS is absorbed more directly into the bloodstream. A small difference, but a difference nonetheless.

Sugar Semantics
Whether we're talking fructose from corn or cane, "sugar is sugar," says Dr. Cate Shanahan, nutritionist for the L.A. Lakers and author of Deep Nutrition: Why Your Genes Need Traditional Food and Food Rules: A Doctor's Guide to Healthy Eating, and that's the real issue. "Your body has no way of tracking whether a molecule of glucose or fructose came from high fructose corn syrup, an apple, or a kale chip. Overeating any kind of sugar is unhealthy, though the specific consequences may differ. Excess glucose can elevate insulin to unhealthy levels, while excess fructose can pack fat into the liver."

In fact, we only need about one teaspoon of sugar in our bloodstream at any given time says Dr. Elisa Lottor, Ph.D., author of Female and Forgetful: A Six-Step Program to Help Restore Your Memory and Sharpen Your Mind and The Regeneration Plan: Our New Paradigm in Healing. The number of teaspoons in a Snickers (#8 on Time's list)? Seven. Our body has to do something with this extra sugar. Where does it go?

Fat, Sick, And Nearly Dead
Insulin is the hormone responsible for getting sugar out of the blood. First, it stores it in the liver and muscles as glycogen, and once they're full, the rest goes to fat. In addition to fat storage, insulin has another unhappy side effect: It often overshoots the mark and drags your blood sugar too low. Ever experienced that junk-food phenomena where no matter what you eat, you're hungry two hours later? This is what's called the blood-sugar "crash" says Dr. Lottor. Typically, when people crash, they reach for more of the sweet stuff, or caffeine (which also raises your blood sugar), or both, which puts them right back on the blood-sugar roller coaster.

What's so bad around riding high? You do this too long and you could develop insulin resistance explains Dr. Lottor. This is a condition where there's so much insulin in your blood, your cells become resistant to it. They close their doors. Insulin can't get sugar into the cells so the sugar stays in the blood. The brain senses this and continues to tell the pancreas to keep pumping out this hormone that can't go anywhere. Ultimately the pancreas gives out and stops producing insulin, a.k.a: Type II Diabetes. But, it doesn't stop there: Insulin resistance has also been linked to stroke, heart disease, hypertension and even cancer. Sugar is no joke.

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Factory Fat
"Nature doesn't make bad fats, factories do," says Dr. Shanahan in Deep Nutrition. So, that's saturated fat and cholesterol, right - those evil fats we've been taught to avoid like shoulder pads? Wrong. In fact, it's just the opposite. Industrial food producers typically use polyunsaturated vegetable oils because they're cheap. They hydrogenate, or add a molecule of hydrogen to the oil to make it more stable and give them a longer shelf life. However, due to their unsaturated nature, when these vegetable oils are overheated they deform, which turns them into toxic compounds says Dr. Shanahan, including - but not limited to - trans fats. This means that all processed products that contain vegetable oil - corn oil, canola oil, soybean oil, sunflower seed oil, cotton seed oil, grapeseed oil, and safflower oil - contain trans fats, because processing uses heat. Pick up your nearest box or bag of food, it doesn't even have to be so-called junk food, any packaged good will do, and you can bet the feed lot one of those oils will be on the ingredients list.

But, The Nutrition Label Says No Trans Fat?
Perhaps, in light of the recent trans-fat fracas, you've checked the labels to find that, what a relief, trans fats appear to be in nothing! Well, buyer beware: According to the CDC, products containing less than 0.5 grams of trans fat per serving can be labeled as having 0 grams trans fat. Which might not seem like a lot, but who eats one serving of anything in one sitting, let alone over a lifetime? Once you pop, the fun don't stop, right? And, all those 0.4s and 0.3s can add up.

The 'C' word
According to Dr. Shanahan, trans fats are not the only cause for concern. There's a far more sinister side to these factory fats: oxidative damage. Again, because vegetable oils are unsaturated, when they are exposed to light, heat, and air (all of which happens during processing and especially during frying) they become oxidized and molecularly deformed. When you eat these damaged fatty acids they can cause other oils inside the body to become oxidized as well. Dr. Shanahan calls this "The Zombie Effect," as these bad fats infect, or oxidize other fats they encounter, setting off a sort of chain of oxidative damage.

But, what does oxidative damage actually mean? Well, we've all heard of antioxidants right? They're good because they fight cancer. That's because oxidants lead to the formation of free radicals - high-energy electrons that have been linked to nearly every modern disease from Alzheimer's to heart disease, depression, and, of course, cancer. In fact, Dr. Shanahan likens eating processed vegetable oils to "eating radiation." Yikes.

Food Dyes
They say we eat with all five senses. Just type in #foodporn on Instagram and you'll be served up an ocular feast of over 20 million images. The food industry has capitalized on this, using artificial dies to make its products, which would otherwise be fifty shades of gray, look like actual food.

The safety of artificial colors has been hotly debated for decades, as they've been linked to allergies, ADHD, and cancer. In fact, Europe has outright banned many of these dyes after the 2007 Southampton study reported a significant increase in hyperactivity in children given drinks with these additives. And, while some dyes have been banned in the United States, due to conflicting results from studies, seven are still legal: Blue No. 1, Blue No. 2, Green No. 3, Red No. 3, Red No. 40, Yellow No. 5, and Yellow No. 6.

According to Dr. Shanahan there is a "correlation not causation" between food dyes and cognitive dysfunction. "All the foods that contain dyes are processed foods, so before we blame food dyes for ADHD we should look at the main ingredients in processed foods that are present in far greater quantity: sugar and vegetable oils." However, we know "toxins are stored in our fat cells," says Dr. Andrea Gore Ph.D, professor of pharmacology and toxicology at the University of Texas. So, when you consider the fact that our brain is composed of a minimum of 60% fat, it's not hard to make the connection between chemicals in our food and major mental dysfunction. Perhaps tasting the rainbow isn't such a good idea after all.

Put Your Hands In The Air And Step Away From The Cheesy Poofs
Does eating junk food mean you're going to wind up with diabetes, cancer, and ADHD? Maybe. Maybe not. The only we've learned from the millions of dollars of research is that no one knows for sure. But, as Lloyd Christmas once said, "You're tellin' me there's a chance?" The important thing to remember is "the dose makes the poison," says Dr. Shanahan. Meaning you can probably have your snack cakes and eat them too - just not every day.

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