21.8: Summary

Food processing is part of the reason why there’s such a large variety of foods to choose from in this country. Many foods are processed in order to make them available year round, to make them safe, and to make them convenient to store, use, and prepare. The food industry is mainly guided by the market, providing consumers with what they want. Many consumers, however, are concerned that processing and the use of additives make foods less healthful.

The loss of nutrients depends in large part on how quickly food moves from the farm to the final product. Commercial processing is often faster than our own procurement and preparation of “fresh” products, resulting in less nutrient loss. Many foods are also commercially fortified, which can provide important nutrients—sometimes just making up for nutrients lost in the processing, sometimes adding more than was there originally.

Processing also affects healthfulness when parts of foods are removed. Removing fat to make low-fat milk is seen as more healthful, and refining whole wheat to make white flour is seen as less healthful. But, generally speaking, foods closest to their original state (“least processed”) tend to be the most healthful.

The names of additives are intimidating and seem “unwholesome” and “unnatural,” but many of them are substances found naturally in food. They include substances taken from other foods, such as ascorbic acid, or pectins, or gums found in plants. But additives also include chemicals that aren’t found naturally in foods, such as certain food colors or some preservatives used to keep microbes under control.

The Delaney Clause prohibits use of any food additive found to cause cancer in any amount in any animal. This Clause has generated a lot of controversy—even among scientists, e.g., arguments as to the validity of animal tests that use extremely large doses of additives, as applied to human usage of much smaller doses. Also, the Delaney Clause doesn’t take into account the weighing of benefits against risk, nor does it apply to toxicants found naturally in food.

In reality, nothing is absolutely safe. There are simply degrees of risk, and assessment of that risk is at best a difficult approximation. It’s also important to consider such things as, what’s the risk relative to other risks, and do benefits outweigh the risk?

The experts put food-borne disease-causing microbes at the top of the list of food hazards. Proper food preparation, sanitation, and refrigeration are important in preventing these illnesses. Microbes can be killed by heat or irradiation, and slowed by freezing, salting, pickling, etc.

Nitrite is added to processed meats to inhibit botulinum, but may be a remote cause of cancer, due to formation of nitrosamines in the stomach. This is an example of the need to balance the risk—a possible increase in risk of stomach cancer—against the benefit of preventing botulism.

Eating a variety of foods is a safeguard against ingesting large amounts of any particular toxin, man-made or natural.