Artificial colorings
The great bulk of artificial colorings used in food are synthetic dyes. For decades synthetic food dyes have been suspected of being toxic or carcinogenic and many have been banned. Whenever possible, choose foods without dyes. They're mostly used in foods of questionable nutritional worth anyway. Natural ingredients should provide all the color your food needs.

Aspartame
This sugar substitute, sold commercially as Equal and NutraSweet, was hailed as the savior for dieters who for decades had put up with saccharine's unpleasant after taste. There are quite a few problems with aspartame. The first is phenylketonuria (PKU). One out of 20,000 babies is born without the ability to metabolize phenylalanine, one of the two amino acids in aspartame. Toxic levels of this substance in the blood can result in mental retardation. Beyond PKU several scientists believe that aspartame might cause altered brain function and behavior changes in consumers. And many people (though a minuscule fraction) have reported dizziness, headaches, epileptic-like seizures, and menstrual problems after ingesting aspartame.

Avoid aspartame if you are pregnant, suffer from PKU, or think that you experience side affects from using it. If you consume more than a couple of servings a day consider cutting back. And, to be on the safe side, don't give aspartame to infants.

BHA & BHT
These two closely related chemicals are added to oil-containing foods to prevent oxidation and retard rancidity. The International Agency for Research on Cancer, part of the World Health Organization, consider BHA to be possibly carcinogenic to humans, and the State of California has listed it as a carcinogen. Some studies show the same cancer causing possibilities for BHT.

BHT and BHA are totally unnecessary. To avoid them read the label. Because of the possibility that BHT and BHA might cause cancer, both should be phased out of our food supply. To play it safe, phase them out of your diet.

Caffeine
Caffeine is found naturally in tea, coffee, and cocoa. It is also added to many soft drinks. It is one of the few drugs -- a stimulant -- added to foods. Caffeine promotes stomach-acid secretion (possibly increasing the symptoms of peptic ulcers), temporarily raises blood pressure, and dialates some blood vessels while constricting others. Excessive caffeine intake results in "caffeinism," with symptoms ranging from nervousness to insomnia. These problems also affect children who drink between 2 to 7 cans of soda a day. Caffeine may also interfere with reproduction and affect developing fetuses. Experiments on lab animals link caffeine to birth defects such as cleft palates, missing fingers and toes, and skull malformations.

Caffeine is mildly addictive, which is why some people experience headaches when they stop drinking it. While small amounts of caffeine don't pose a problem for everyone, avoid it if you are trying to become or are pregnant. And try to keep caffeine out of you child's diet.

Note: Caffeine can be ingested in cases of severe migraine headaches to quickly relieve pain due to its dilating effects.

Monosodium Glutamate (MSG)
Early in this century a Japanese chemist identified MSG as the substance in certain seasonings that added to the flavor of protein-containing foods. Unfortunately, too much MSG can lead to headaches, tightness in the chest, and a burning sensation in the forearms an the back of the neck. If you think you are sensitive to MSG, look at ingredient listings. Also, avoid hydrolyzed vegetable protein, or HVP, which may contain MSG.

Nitrite and Nitrate
Sodium nitrite and sodium nitrate are two closely related chemicals used for centuries to preserve meat. While nitrate itself is harmless, it is readily converted to nitrite. When nitrite combines with compounds called secondary amines, it forms nitrosamines, extremely powerful cancer-causing chemicals. The chemical reaction occurs most readily at the high temperatures of frying. Nitrite has long been suspected as being a cause of stomach cancer. Look for nitrite-free processed meats -- some of which are frozen, refrigeration reduces the need for nitrites -- at some health food and grocery stores. But regardless of the presence of nitrite or nitrosamines, the high-fat, high-sodium content of most processed meats should be enough to discourage you from choosing them. And don't cook with bacon drippings.

Olestra
Olestra, the fake fat recently approved by the Food and Drug Administration (FDA), is both dangerous and unnecessary. Olestra was approved over the objection of dozens of leading scientists.

The additive may be fat-free but it has a fatal side-effect: it attaches to valuable nutrients and flushes them out of the body. Some of these nutrients -- called carotenoids -- appear to protect us from such diseases as lung cancer, prostate cancer, heart disease, and macular degeneration. The Harvard School of Public Health states that "the long-term consumption of olestra snack foods might therefore result in several thousand unnecessary deaths each year from lung and ,prostate cancers and heart disease, and hundreds of additional cases of blindness in the elderly due to macular degeneration. Besides contributing to disease, olestra causes diarrhea and other serious gastrointestinal problems, even at low doses."

FDA certified olestra despite the fact that there are safe low-fat snacks already on the market. There is no evidence to show that olestra will have any significant effect on reducing obesity in America.

Despite being approved as safe by the FDA, all snacks containing olestra must carry a warning label (similar to one found on cigarettes) that states:

This Product Contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E, and K have been added.

CSPI advises consumers to avoid all olestra foods, and urges major food manufacturers not to make olestra-containing products.

Potassium Bromate
This additive has long been used to increase the volume of bread and to produce bread with a fine crumb (the non-crust part of bread) structure. Most bromate rapidly breaks down to form innocuous bromide. However, bromate itself causes cancer in animals. The tiny amounts of bromate that may remain in bread pose a small risk to consumers. Bromate has been banned virtually worldwide except in Japan and the United States. It is rarely used in California because a cancer warning is required on the label.

Sulfites
Sulfites are a class of chemicals that can keep cut fruits and vegetables looking fresh. They also prevent discoloration in apricots, raisins, and other dried fruits; control "black spot" in freshly caught shrimp; and prevent discoloration, bacterial growth, and fermentation in wine. Until the early 80's they were considered safe, but CSPI found six scientific studies proving that sulfites could provoke sometimes severe allergic reactions. CSPI and the Food and Drug Administration (FDA) identified at least a dozen fatalities linked to sulfites. All of the deaths occurred among asthmatics. In 1985 Congress finally forced FDA to ban sulfites from most fruits and vegetables. Especially if you have asthma, be sure to consider whether your attacks might be related to sulfites. The ban does not cover fresh-cut potatoes, dried fruits, and wine.

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http://www.cspinet.org/reports/food.htm