For thousands of years, man ate only fresh food; fruits, vegetables, grains, and meat went straight from the wilderness or the field to our plates. Today, a majority of foods found on supermarket shelves in North America are loaded with potentially harmful chemical additives, preservatives and other dangerous substances.

But just how dangerous are artificial sweeteners? How about antioxidant preservatives? And what's the deal with all those weird-sounding ingredients you can't even pronounce?

Some food additives aren't necessarily dangerous for everyone and others need more testing before a definite verdict can be established, but some can without a doubt pose serious health risks. Read on to find out which additives you shouldn't touch with a 10-foot pole.

Note: The following additives are all legal in the United States.

Preservatives

Propyl Gallate

An antioxidant preservative that prolongs the life of fats and oils — such as in vegetable oil, chewing gum, meat products, and chicken soup base — propyl gallate may cause cancer. It is often used with BHA and BHT (see below).

BHA & BHT

Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) also delay rancidity in fats, oils, and foods that contain oils, such as cereals, chewing gum, vegetable oil, and potato chips. Some studies have shown that both BHA and BHT cause cancer in rats. Since they can easily be replaced by safer alternatives like vitamin E or packing under nitrogen instead of air, or even be completely left out, there is no reason to take the chance; avoid these chemicals as much as possible.

Sodium Nitrite & Sodium Nitrate

Sodium nitrite is added to cured meat like cold cuts and hot dogs to keep their color and to give them flavor; sodium nitrate can be used for the same purpose, as it breaks down into sodium nitrite. In addition to their preservative functions, they are used to prevent botulism, a deadly disease transmitted through food.

Unfortunately, during the digestive process, they form cancer-causing nitrosamines in our intestines.

Given this fact, most foods that contain sodium nitrite are also pumped with vitamin C derivatives like ascorbate or sodium erythrobate, as vitamin C prevents nitrosamines from forming. However, if you're still worried, avoid food containing sodium nitrite or eat vitamin C-rich foods — such as oranges, broccoli, green peppers, and Brussels sprouts — at the same time.

Artificial Sweeteners

Saccharin

This sweetener, commercially known as Sweet'N Low, is 350 times sweeter than sugar; it is used in many diet foods and soft drinks, and as a tabletop sugar substitute. Several animal studies have shown that it causes cancer of the bladder, uterus, ovaries, blood vessels, skin, and various other organs. Even a significant study conducted by the National Cancer Institute found that it does indeed cause bladder cancer.

There has been an ongoing battle between the FDA and the diet-food industry over the past 10 years regarding the ban or use of warning labels on products containing saccharin, but as of 2000, all warnings were removed. However, evidence shows that it is probably safer to stay away from it.

Acesulfame-K

Acesulfame-K is approximately 200 times sweeter than sugar and is used around the world in baked goods, soft drinks, chewing gum, and gelatin desserts. Although early studies showed no health risks, they were not the most reliable experiments. Since then, two separate studies on rats have shown that it may cause cancer. Although further tests are needed, it is recommended to avoid acesulfame-K altogether.An added concern is that the breakdown product of acesulfame-K known as acetoacetamide affects the thyroid in rats, dogs and rabbits when administered in large amounts; however, there is no proof that the amounts found in food are dangerous.

Aspartame

Aspartame is found in the name brands Equal and NutraSweet; it is composed of methanol and two amino acids. Although originally believed to be the perfect artificial sweetener, it caused brain tumors in rats in certain studies conducted in the 1970s.

Although there was much pressure from different groups for further studies to explore the potential dangers of aspartame, it wasn't until 2005 that a new study was released. It found that even small doses of the sweetener increased the occurrence of lymphoma and leukemia, and occasionally caused brain tumors in rats. Although more research is still needed, avoid it to stay on the safe side.However, do not believe the claims that can be found all over the Internet regarding the wide variety of illnesses caused by aspartame; most of them have never been proven.

Artificial Colorings

Blue 1 & Blue 2

Blue 1 is a coloring used in candy, beverages and baked goods. Although more research is needed, some studies have shown a small cancer risk, so it is wise to steer clear of it.Blue 2 can be found in pet food, candy and beverages. It hasn't been proven without a doubt, but studies have suggested that it causes brain tumors in mice.

Red 3

Used in fruit cocktail cherries, baked goods and candy, there is some evidence that Red 3 causes thyroid tumors in rats. Although it is unclear if this could also be the case in humans, it is a possibility.

Yellow 6

Found in beverages, baked goods, sausages, candy, and gelatin, Yellow 6 is the third most widely used of all food colorings. It has been shown to cause adrenal gland and kidney tumors, and it contains small amounts of many carcinogens. However, after review, the FDA concluded that it isn't a significant cancer risk for humans, but it may still be wise to avoid it.

Eat Fresh

Although most of these additives have not been proven without a doubt to be dangerous, and there are many more that could be added to this list, it is safer to stay away from the aforementioned chemicals as much as possible. Read the labels; if you have a choice between a bag of potato chips that contains BHA and BHT, and one that doesn't, choose the latter. Or better yet, why don't you just go for some fresh veggies and dip, and you'll avoid the processed ingredients altogether.

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