Reader question: We know preservatives are not good for us but sometimes we just have no choice if we want to eat a certain food. We’d like to know which preservatives we should absolutely stay away from, and, are guar gum and xanthan gum in that group?
Linda M.

When reading labels, my mind typically defaults to the term “preservatives” whenever I see an ingredient that’s not just a whole food.

Truly, though, these types of ingredients really should be lumped into the general class “additives”, and that group can be divided into the subclasses of preservatives, thickeners, and colors and flavors, among others.

Unfortunately, the safety of these food additives is not black and white. Some additives may be perfectly fine for one individual, while causing an allergic reaction, or very uncomfortable digestive issue, in another. The variety of food additives and their potential impact is much too large for the scope of this article, but I’ll give an overview of a few common additives and their relative safety.

Preservatives

BHA (butylated hydroxyanisole), BHT (butylated hydroxytoluene), and EDTA (ethylenediaminetetraacetic acid):

These preservatives fall into the category of “If You Can’t Say It, Don’t Eat It”! The purpose of these additives is to maintain the integrity of the oils contained in the processed food. This prevents the degradation of taste and general food spoilage. These chemicals may cause allergic reactions, cancer, and behavioral changes or hyperactivity in children. They are best avoided, not only because of above issues plus their potential toxicity to the nervous system but because foods requiring them are never the most nutritious choice. BHA, BHT, and EDTA are commonly found in cereals and crackers.

Nitrites/Nitrates:

These chemicals are most commonly used in cured meats, like bacon, ham, bologna and the like. They prevent the discoloration of the meat, as well as its spoilage. Both compounds can be broken down into nitrosamines in the body, which are powerful carcinogens, or cancer-causing agents. This chemical process can be prevented by supplementing with vitamin C. I recommend minimizing processed meats in the diet and including only small amounts. These kinds of meats should not be making up the main protein source in meals.

Sulfites:

Sulfites preserve foods by preventing bacterial growth. They can be found on such items as pre-cut apples because they keep the apples looking fresh instead of brown. They are often added to wines and sprayed on salad bar offerings. While sulfites are naturally occurring substances, there is a long list of potential side effects, including diarrhea, nausea, and headache. Those with asthma often suffer with greater symptoms from sulfite irritation. This is another group you are better off avoiding. The convenience of pre-cut food is just not worth the risk.

Thickeners

Guar Gum:

This is an additive commonly found in “natural” foods. It is a fiber derived from the guar bean and is used as a thickener. Similar to other fibers, it has been shown to be beneficial in normalizing both digestive processes and blood sugar levels. There is some question, however, as to the safety of its use in pregnant women.

Xanthan Gum:

This is a relatively natural additive. Made from the bacterial fermentation of corn sugar, it is used to give thickly liquid foods a uniform consistency. It has been shown to be safe at even high quantities.

Carrageenan:

This seaweed extract is Generally Regarded As Safe (GRAS). It is used in many processed foods such as ice cream, cheeses, puddings, and jellies. More research is needed, though, because there are implications in it being bothersome to those with Irritable Bowel Syndrome, and well as holding potential for causing digestive system cancers.

Multi-use

Aluminum salts:

Aluminum is used in foods for a variety of purposes, but primarily as an anti-caking agent (keeps powders from clumping). Aluminum is found in great quantities in the earth’s crust but has only been introduced quite recently into our bodies. In fact, our liver does not even have a pathway for detoxifying aluminum. Aluminum buildup has been implicated in Alzheimer’s, a variety of cancers, and asthma. For this reason, I recommend avoiding aluminum not just in foods, but in foil, cookware, and deodorant.

A final thought on processed foods:

I’ve felt a slight wave of apprehension in putting my faith in the honesty and integrity of food manufacturers. Can we really believe that all ingredients are listed on the label? The sad truth is no. There are loopholes food producers can take to avoid full disclosure, specifically that of indirect additives. These are potentially harmful chemicals and additives used in the production of the ingredients in foods, as well as compounds found in the packaging of food. It only takes a little imagination to visualize a long chain of compounds linking up the actual product you buy at the store. While this may make the whole idea of food selection utterly overwhelming, there is one big takeaway I’ve already touched on: buy foods in their most whole states, fresh and local if possible. If food additives frustrate you, you still have immense power: Just opt out!

There are many, many other additives in our food system. Which ones do you have questions about?

Source: Haas, E. M. Staying Healthy with Nutrition. 2006. Ten Speed Press, New York.