Some of the gross stuff (a.k.a. food additives) we eat on a daily basis

If you believe that old adage that you are what you eat, you must be having an identity crisis these days. With so many things in our food that surprise and even disgust us, we seem to never be sure if we know exactly what we're eating.

Recently consumers have been outraged at so-called pink slime being added to hamburger meat — or the use of ammonium hydroxide in processing. And vegetarians were surprised to learn that their Starbucks Strawberry and Cream Frappuccino contained crushed up cochineal beetles.

This week, the Conference Board of Canada released a report showing that Canadians are eating way too much salt, sugar and unhealthy fats. The authors blame processed food and they want to see better standards and labeling.

But that's just the beginning.

"If you were grossed out by pink slime," Sarah Klein, a lawyer with the Washington-based Center for Science in the Public Interest tells Cleveland.com earlier this year, "there's more to come."

The Huffington Post and CBS News have each recently compiled lists of food additives that are far from appetizing.

We've run some of the questionable ingredients past University of Guelph nutrition and toxicology professor James Kirkland to find out whether they are as bad as they sound.

Also see: Eat fish, lower your colon cancer risk: study

Bacteriophages

These are bacteria-killing viruses that are sprayed on deli products to ward off things like E. coli and Listeria, or the bacteria that causes botulism.

Kirkland says the use of bacteriophages is probably a lot better than what was done in the past.

"Traditionally the thing that protected us most against botulism was nitrite preservation," he explains. "Nitrite preserved meat decreases your risk for things like botulism and salmonella poisoning, but in the long term they increase your risk of stomach cancer."

Nitrite is still used, but in minimal amounts. So a bacteria-killing virus such as bacteriophages, while pretty gross, might actually be the better of two evils.

Gelatin

The product that makes Jello jiggle is made from collagen, and it's often taken from animal skins.

It can also show up in yogurt, candy and sour cream.

Vegetarians might not be pleased, and Kirkland says it's a poor quality protein, as it lacks the amino acid tryptophan.

So, don't expect your Jello to serve as a balanced meal. And watch out when serving your vegetarian friend yogurt.

Castoreum

An extract taken from the beaver's perineal glands, found next to the animal's anus, castoreum is used to enhance flavours.

"In the case of strawberry and raspberry flavourings," food blogger Bruce Bradley tells the Huffington Post, "some natural berry flavors may actually be enhanced by castoreum."

"It's not something I would consume without some care," says Kirkland. "But that's the first I've heard of it."

Ammonium Sulfate

Best known as a component used in cleaners and fertilizers, this salt compound that includes nitrogen is also found in many breads, including Subway sandwich buns.

While it might sound scary, Kirkland says these chemicals are normal body chemicals.

"Both halves of that are natural chemicals."

So no need to worry about that one.

Also see: Red wine can aid in good bacteria growth, says study

L-Cysteine

While this is a natural amino acid, consumers might be shocked to find out that it is produced through processing human hair and duck feathers. You'll find it in some bread products. But Kirkland doesn't think we should be too alarmed.

"Hair and feathers are made of protein," explains Kirkland. "They would go through pretty harsh digestive conditions to release the amino acids. I wouldn't be too concerned."

Cellulose

It might seem gross to have wood pulp added to your shredded cheese to keep the strands from clumping together, or to your low-fat ice cream to make it creamier

But it seems that cellulose is actually good for you. It'll give you some fibre with that low-fat desert.

"As an insoluble fibre, it's good for your colon function," says Kirkland. "It's a health food component in its natural state, so hopefully they haven't put any contaminants in it."

Titanium Dioxide

A metal that's found in sunscreen, and also as a food lightener. It makes skim milk lighter and is sometimes used in coffee creamers and frosting, according to Men's Health.

"Compared to a lot of other metals, it's about as inert as metals come," says Kirkland. "When small particles of something are inert, generally they aren't a big concern."

That said, he'll pass on having any metal added to his milk.

"I would prefer not to have cosmetic ingredients in my food," he says. "But if there's two things of milk on the shelf in clear packaging, you're going to buy the one that's whiter. That's what the public does."

Watch the video below about the recent controversy over a TIME magazine cover featuring a breastfeeding mom.