Feb 19, 2014
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Bread

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Nutritional Profile

Energy value (calories per serving): Moderate

Protein: Moderate Fat: Low to moderate Saturated fat: Low to high Cholesterol: Low to high Carbohydrates: High

Fiber: Moderate to high

Sodium: Moderate to high

Major vitamin contribution: B vitamins

Major mineral contribution: Calcium, iron, potassium

About the Nutrients in This Food

All commercially made yeast breads are approximately equal in nutri- tional value. Enriched white bread contains virtually the same amounts of proteins, fats, and carbohydrates as whole wheat bread, although it may contain only half the dietary fiber (see flour).

Bread is a high-carbohydrate food with lots of starch. The exact amount of fiber, fat, and cholesterol in the loaf varies with the recipe. Bread’s proteins, from grain, are low in the essential amino acid lysine. The most important carbohydrate in bread is starch; all breads contain some sugar. Depending on the recipe, the fats may be highly saturated (butter or hydrogenated vegetable fats) or primarily unsaturated (vegetable fat).

All bread is a good source of B vitamins (thiamin, riboflavin, niacin), and in 1998, the Food and Drug Administration ordered food manufactur- ers to add folates—which protect against birth defects of the spinal cord and against heart disease—to flour, rice, and other grain products. One year later, data from the Framingham Heart Study, which has followed heart health among residents of a Boston suburb for nearly half a cen- tury, showed a dramatic increase in blood levels of folic acid. Before the fortification of foods, 22 percent of the study participants had a folic acid deficiency; after, the number fell to 2 percent.

Bread is a moderately good source of calcium, magnesium, and phos- phorus. (Breads made with milk contain more calcium than breads made without milk.) Although bread is made from grains and grains contain phytic acid, a natural antinutrient that binds calcium ions into insoluble, indigestible compounds, the phytic acid is inactivated by enzyme action during leavening. Bread does not bind calcium.

All commercially made breads are moderately high in sodium; some contain more sugar than others. Grains are not usually considered a good source of iodine, but commer- cially made breads often pick up iodine from the iodophors and iodates used to clean the plants and machines in which they are made.

Homemade breads share the basic nutritional characteristics of commercially made breads, but you can vary the recipe to suit your own taste, lowering the salt, sugar, or fat and raising the fiber content, as you prefer.

The Most Nutritious Way to Serve This Food

As sandwiches, with cheese, milk, eggs, meat, fish, or poultry. These foods supply the essen- tial amino acid lysine to “complete” the proteins in grains.

With beans or peas. The proteins in grains are deficient in the essential amino acids lysine and isoleucine and rich in the essential amino acids tryptophan, methionine, and cystine. The proteins in legumes (beans and peas) are exactly the opposite.

Diets That May Restrict or Exclude This Food

Gluten-free diet (excludes breads made with wheat, oats, rye, buckwheat and barley flour) Lactose-free diet

Low-fiber diet (excludes coarse whole-grain breads) Low-sodium diet

Buying This Food

Look for: Fresh bread. Check the date on closed packages of commercial bread.

Storing This Food

Store bread at room temperature, in a tightly closed plastic bag (the best protection) or in a breadbox. How long bread stays fresh depends to a great extent on how much fat it contains. Bread made with some butter or other fat will keep for about three days at room tempera- ture. Bread made without fat (Italian bread, French bread) will dry out in just a few hours; for longer storage, wrap it in foil, put it inside a plastic bag, and freeze it. When you are ready to serve the French or Italian bread, you can remove it from the plastic bag and put the foil- wrapped loaf directly into the oven.

Throw away moldy bread. The molds that grow on bread may produce carcinogenic toxins.

Do not store fresh bread in the refrigerator; bread stales most quickly at temperatures just above freezing. The one exception: In warm, humid weather, refrigerating bread slows the growth of molds.

When You Are Ready to Serve This Food

Use a serrated knife to cut bread easily.

What Happens When You Cook This Food

Toasting is a chemical process that caramelizes sugars and amino acids (proteins) on the surface of the bread, turning the bread a golden brown. This chemical reaction, known both as the browning reaction and the Maillard reaction (after the French chemist who first identified it), alters the structure of the surface sugars, starches, and amino acids. The sugars become indigestible food fiber; the amino acids break into smaller fragments that are no longer nutritionally useful. Thus toast has more fiber and less protein than plain bread. How- ever, the role of heat-generated fibers in the human diet is poorly understood. Some experts consider them inert and harmless; others believe they may be hazardous.

How Other Kinds of Processing Affect This Food

Freezing. Frozen bread releases moisture that collects inside the paper, foil, or plastic bag in which it is wrapped. If you unwrap the bread before defrosting it, the moisture will be lost and the bread will be dry. Always defrost bread in its wrappings so that it can reabsorb the moisture that keeps it tasting fresh.

Drying. Since molds require moisture, the less moisture a food contains, the less likely it is support mold growth. That is why bread crumbs and Melba toast, which are relatively mois- ture-free, keep better than fresh bread. Both can be ground fine and used as a toasty-flavored thickener in place of flour or cornstarch.

Medical Uses and/or Benefits

A lower risk of some kinds of cancer. In 1998, scientists at Wayne State University in Detroit conducted a meta-analysis of data from more than 30 well-designed animal studies mea- suring the anti-cancer effects of wheat bran, the part of grain with highest amount of the insoluble dietary fibers cellulose and lignin. They found a 32 percent reduction in the risk of colon cancer among animals fed wheat bran; now they plan to conduct a similar meta- analysis of human studies. Breads made with whole grain wheat are a good source of wheat bran. NOTE : The amount of fiber per serving listed on a food package label shows the total amount of fiber (insoluble and soluble).

Early in 1999, however, new data from the long-running Nurses Health Study at Brigham Women’s Hospital/Harvard University School of Public Health showed that women who ate a high-fiber diet had a risk of colon cancer similar to that of women who ate a low fiber diet. Because this study contradicts literally hundreds of others conducted over the past 30 years, researchers are awaiting confirming evidence before changing dietary recommendations.

Calming effect. Mood is affected by naturally occurring chemicals called neurotransmitters that facilitate transmission of impulses between brain cells. The amino acid tryptophan amino acid is the most important constituent of serotonin, a “calming” neurotransmitter. Foods such as bread, which are high in complex carbohydrates, help move tryptophan into your brain, increasing the availability of serotonin.

Adverse Effects Associated with This Food

Allergic reactions and/or gastric distress. Bread contains several ingredients that may trigger allergic reactions, aggravate digestive problems, or upset a specific diet, among them gluten (prohibited on gluten-free diets); milk (prohibited on a lactose- and galactose-free diet or for people who are sensitive to milk proteins); sugar (prohibited on a sucrose-free diet); salt (controlled on a sodium-restricted diet); and fats (restricted or prohibited on a controlled-fat, low-cholesterol diet).

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