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Carbohydrate Basics


Carbohydrates in Nutrition and Obesity
Long before processed foods, 24-hour convenience marts, and grocery stores that carry thousands of foods under one roof, humans ate foods in their natural, whole state. Foods that were good sources of fiber and other complex carbohydrates, including fruits, vegetables, nuts, and seeds, were a significant part of the human diet. We ate what nature provided, the way nature provided it.

carbohydrates in nutrition and obesity
©2006 Publications International, Ltd.
Eating fewer highly refined processed
foods and
more whole grains and whole
fruits and vegetables 
is better for our
 health and for controlling weight.

That began to change with the advent of new technologies that allowed us to process foods in a way we never had before. Not only did we learn to mill whole grains in volume to feed an ever-growing population, but we also learned how to refine them even further into white flour. While pricey, the white flour gave breads and other baked goods more visual and textural appeal. This was not lost on the upper class, who flaunted their higher social status by serving foods prepared with refined, white flour.

As revolutionary as this new food processing method was, there was an unfortunate side effect that people weren't aware of immediately. Refinement stripped the grains of most of the nutrients that Mother Nature had built in. But it wasn't just grains that technology was processing. Oranges, a luxury item by themselves, were even more prized in their processed juice form. This unique imported food was advertised in local newspapers, and the upper class bought it, too, as a sign of social status. Unfortunately, some of the nutrients available in whole oranges, particularly fiber, disappeared in processing. Food processing increased the choices available to consumers, but at a nutritional price.

As merchants responded to the need for a year-round food supply by carrying larger inventories, they also needed a way to extend shelf life. Food manufacturers were happy to comply and quickly discovered the profitability of adding preservatives. Fortunately, they also discovered the need to add back nutrients lost in processing, and they developed the ability to do that through enrichment and fortification of their products.

Through the years, many of the ingredients used to extend shelf life, improve palatability, and decrease production costs to manufactured foods have come under fire for their negative impact on the quality of human nutrition. Stripping foods of their natural vitamin, fiber, and mineral package while adding artificial colors, sweeteners, and other additives is not the healthiest or wisest use of technological advancement. Partly out of interest in prevention and partly in response to the steady increase in type 2 diabetes and obesity, as well as the high rate of heart disease and certain cancer diagnoses, the pendulum has slowly begun to swing in the opposite direction. While it's impossible as well as impractical to return to the days when food wasn't refined or preserved in any way, there is increasing recognition that eating fewer highly refined processed foods and more whole grains and whole fruits and vegetables is better for our health and for controlling weight.

Changing diet trends

The link between nutrition, health, and disease grows stronger daily. In the early 1970s, much of the nutrition research linked fat, particularly saturated fat, to heart disease and obesity. But even as the evidence continued to accumulate throughout the 1980s, there seemed to be a disconnect in the message delivery: Americans were growing as well! In fact, according to the Centers for Disease Control, in the last ten years obesity rates have increased by more than 60 percent among adults. Since 1980, obesity rates have doubled among children and tripled among adolescents.

carbohydrates in nutrition and obesity
©2006 Publications International, Ltd.
While white flour may have more
commercial appeal, it does not contain
as many nutrients as whole grains.

During the mid- to late-1980s, food scientists and manufacturers began working to become part of the solution to the growing obesity problem by developing fat-free and low-fat foods. Since fat has more than double the calories found in protein and carbohydrate, it seemed reasonable to assume that cutting fat in foods was a good way to cut calorie consumption overall. Consumers eagerly jumped on the bandwagon, buying lots of fat-free products. However, much to everyone's surprise, obesity rates continued to climb at an alarming rate. Why? The fat-free products contained considerably more refined carbohydrate (sugar) to substitute for the loss of flavor from fat. The products may have been fat free, but they weren't calorie free. But people acted as if they were, consuming huge quantities of processed fat-free cookies, crackers, and other goodies.

When fat-free foods didn't appear to be the answer to the skyrocketing obesity rate, people began looking for the next solution. The focus eventually shifted from counting fat grams to counting carbohydrate grams. The theory was the fewer carbohydrates the better. Where fat was concerned, however, all caution was thrown to the wind. As long as people could build a meal around a miniscule amount of carbohydrate, they could eat as much fat and protein as they liked, and the weight was guaranteed to come off. And for some it did come off. But there were unpleasant side effects: Many people who cut carbs significantly felt less energetic and experienced constipation and bloating. And when they ceased to adhere closely to a reduced-carb diet, the weight crept back on. Obesity rates continued to climb. Heart disease remains the number-one killer, and type 2 diabetes is becoming epidemic.

As you can see, it's a mistake to blame carbohydrate alone for obesity and nutrition-related diseases. It is absolutely true, however, to say that the type as well as the amount of carbohydrate that we eat is crucial to good health. We all know that a jelly donut is a carbohydrate food, but it's worlds apart from a whole-wheat bagel in terms of good nutrition. That's what we're talking about here: keeping carbohydrates in the diet but choosing the most nutritious among them.

Enriched and Fortified Foods
More than 90 percent of ready-to-eat cereals and breads, as well as almost all types of processed foods, are enriched or fortified with vitamins, minerals, or fiber. Fortification and enrichment are two of the most effective methods for improving health and preventing nutritional deficiencies that cause disease. In the United States, diseases such as goiter, rickets, beriberi, and pellagra have been virtually eliminated because of these processes.

Originally, the goal of enrichment was simply to replenish the nutrients lost during food processing. Enriched means that nutrients are added back to foods. For instance, white flour is enriched with B vitamins and iron, which are removed from wheat flour when it is refined.

The concept was later expanded to include adding other substances that were not present in the food before processing. The aim of fortifying foods was to eradicate nutritional deficiencies associated with diseases. Fortified means nutrients that are often lacking in typical diets have been added. For example, salt is often fortified with iodine because there are few dietary sources of it.

While vitamins and minerals are still added to processed foods to maintain or improve our current nutritional health, the use of fortification today helps to reduce and prevent devastating and sometimes fatal diseases, such as spina bifida and anencephaly. Fortification of bread, pasta, and other cereal grains with folic acid has been directly responsible for the 26 percent annual decrease in these two birth defects.

Fortification and enrichment may even be new weapons in the fight against heart disease. The amino acid homocysteine is being increasingly accepted as a marker for heart disease risk. High homocysteine and low B vitamin concentrations have been linked to increased risk of cardiovascular disease. Although the role that folic acid and other B vitamins play in heart disease protection still needs to be confirmed, there is encouraging research indicating that fortifying cereals and other foods with folic acid and other B vitamins may help protect against heart disease risk by lowering homocysteine levels.

©Publications International, Ltd.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.