The Encyclopedia Of Nutrition And Good Health - S pdf

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The Encyclopedia Of Nutrition And Good Health - S pdf

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saccharin One of the oldest ARTIFICIAL SWEETEN- ERS, saccharin has been available for more than 100 years. It is not metabolized in humans and it pro- vides no calories. Although saccharin is 300 to 700 times sweeter than TABLE SUGAR, it is often per- ceived to have a bitter or “metallic” aftertaste at high concentrations. Saccharin is generally com- bined with a sugar, DEXTROSE, or with ASPARTAME, another artificial sweetener, for tabletop sweeten- ers. The compound is stable to baking and acidic conditions; this versatility contributes to its use in many products, including baked foods, salad dress- ings, reduced calorie jams, toothpaste, mouthwash, and other personal care products. Saccharin can be added to chewing gum where it is used with SOR- BITOL, a sweet sugar analog. In May 2000 officials at the National Institute of Environmental Health Sciences and its subdivision, the National Toxicology Program, announced that saccharin would no longer appear on their list of “cancer threats.” Saccharin had officially been listed as a carcinogen in March 1977 when Cana- dian researchers discovered a link between saccha- rin and bladder tumors in male rats. This finding immediately triggered the threat of the DELANEY CLAUSE , a congressionally mandated provision that requires the U.S. Food and Drug Administration to ban any synthetic food chemical shown to cause cancer when ingested by laboratory animals. When millions of dieting Americans heard that the only low-calorie sweetener available was going to be banned (cyclamates had been banned in 1970 for similar reasons), they were upset; Congress responded by protecting saccharin from the Delaney Clause by allowing it back on the market with a health warning label. Saccharin’s chances were further damaged in 1981 when the National Toxicology Program, referring again to the Cana- dian rat study, decided to put saccharin on its “can- cer causing” list—formally declaring it an “antici- pated human carcinogen.” In September 1996 the Calorie Control Council, a trade group of the diet food industry, petitioned the toxicology program to have saccharin reclassi- fied. Subsequently, two government scientific pan- els that looked at the possible link between saccharin and cancer supported removal, saying that any link to cancer was weak. A third scientific panel of nongovernment experts voted 4–3 against taking saccharin off the list. Nevertheless, in December 2000 Congress passed the Saccharin Warning Elimination via Environ- mental Testing Employing Science and Technology Act (“SWEETEST Act”) after a National Toxicology Program review concluded that saccharin poses no health hazard to humans. The report concluded that the observed bladder tumors in rats were caused by mechanisms not relevant to humans and that no data in humans suggest that a carcinogenic hazard exists. The legislation allowed manufactur- ers to remove the warning labels from saccharin packages that said the sweetener had been shown to cause cancer in lab animals. (See also FOOD ADDI- TIVES ; NATURAL SWEETENERS.) S-adenosylmethionine (SAMe) A synthetic form of the AMINO ACID METHIONINE, S-adenosylmethion- ine is found in every cell in the human body. SAMe has been used in Europe since the 1960s as a prescription antidepressant and pain reliever and was introduced to the U.S. market in 1999 as a dietary supplement. In the body SAMe normally maintains cell membranes and is involved in methylation, a process that, among other things, helps to regulate levels of the mood-lifting neurotransmitters sero- S 565 tonin and dopamine. Some study subjects have reported that SAMe is effective as an antidepres- sant. Several clinical studies have demonstrated that SAMe is better than placebo and is equivalent to nonsteroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen for easing pain associated with osteoarthritis. Patients suffering from fibromyalgia have also reported significant relief from the symp- toms that accompany that disease. SAMe has also shown some promise in treating patients who suf- fer liver diseases such as cirrhosis (liver failure) caused by alcohol abuse. Because SAMe was introduced in the United States as a dietary supplement, it has not under- gone review by the U.S. FDA for safety or efficacy, and many scientists and others in the medical com- munity have expressed skepticism regarding its reported health benefits. These critics say the study subjects may have been reporting PLACEBO effects and that all the studies that have been done so far were for periods of time that were too short to pro- duce statistically significant results. Additional studies are ongoing. Safety data are inadequate for pregnant and breast-feeding women. Soekin, A. L. “Abstract: Safety and Efficacy of S-adeno- sylmethionine (SAMe) for Osteoarthritis,” Journal of Family Practice 51, no. 5 (2002): 425–430. safflower (Carthamus tinctorius) A thistle-like plant that produces oil-rich seeds resembling small sunflower seeds. Safflower is a late arrival in the United States, becoming an established crop only in the 1950s and 1960s as POLYUNSATURATED VEG- ETABLE OILS gained in popularity in response to fears about CHOLESTEROL and SATURATED FAT and their link to ATHEROSCLEROSIS. Varieties of saf- flower yielding 50 percent oil have been devel- oped. Safflower is cultivated in California and Montana. Safflower oil contains the highest percentage of polyunsaturated FATTY ACIDS and the lowest per- centage of saturated fatty acids among commer- cially available oils. Typically, safflower oil contains 74 percent to 77 percent LINOLEIC ACID, an essential polyunsaturated fatty acid; 16.4 percent OLEIC ACID, a monounsaturated fatty acid; and 6.6 percent sat- urated fatty acids. Like SOYBEAN oil, it has a high smoke point (440° to 480° F) and is often used in deep-fat frying and sauteeing. Safflower oil is rich in VITAMIN E. As a polyunsaturated oil, it is suscep- tible to RANCIDITY (decomposition) when heated. These oils should not be reheated. Like all commercial polyunsaturated cooking oils, safflower is partially hydrogenated to reduce its susceptibility to oxidation and decrease the rate of rancidity. Hydrogenation refers to the chemical hardening process that adds hydrogen atoms and decreases the level of saturation. Hydrogenated safflower oil yields MARGARINE, VEGETABLE SHORTEN - ING, MAYONNAISE, and other products. Hydrogena- tion creates TRANSFATTY ACIDS. The safety of these unusual products has been questioned. The consumption of polyunsaturated vegetable oils like safflower oil can lower the level of LOW- DENSITY LIPOPROTEIN (LDL), the less desirable form of cholesterol, but at the same time a high intake can lower the level of HIGH-DENSITY LIPOPROTEIN (HDL), the desirable form of cholesterol. (See also ESSENTIAL FATTY ACIDS.) saffron (Crocus sativus) This small crocus pro- duces flowers with intense yellow-orange fila- ments. When dried, the stamens yield a pungent spice and brilliant yellow coloring agent. Saffron is used for rice dishes, soup, and sauces, as well as certain meat dishes in Indian, Italian, and Span- ish cuisine. Saffron is best dissolved in a small amount of warm water before use for uniform mixing. (See also FOOD ADDITIVES; FOOD COLORING, NATURAL.) sage (Salvia officinalis) A common perennial HERB whose fresh or dried leaves add a pungent, bitter taste to foods. There are over 500 varieties of sage, including the common garden sage. It is used to flavor poultry, fatty meat like pork, veal, ham, or lamb, and in marinades, minestrone, and sauces. Sage has long been used as a medicinal herb in folk medicine. Its name comes from the Latin salvus, which means healthy. It possesses bacterial and antifungal properties and it has been used to aid digestion. Sage tea has been used to reduce cough- ing associated with colds and for irregular men- struation. As with any medicinal herb, the consumption of large amounts for long periods of time is not recommended. (See also PARSLEY.) 566 safflower sago Starch from the trunk of a tropical palm. In the South Pacific, sago palm flour and starch are staple foods. They are used as food thickeners. Commercially, sago starch is used as a noncorn source of glucose from which to manufacture corn- free VITAMIN C for certain individuals who are ultra- sensitive to corn products. (See also OIL PALM; PALM OILS .) salami A deli sausage usually made from PORK or a combination of pork and BEEF and several seasonings, including salt, garlic, black pepper, and fennel. Salami is a high-fat (generally 30 per- cent) and high-sodium food. Some, but not all, salamis are cured and may contain preservatives such as nitrites. Several varieties are available, including cacciatore, pepperoni, and genoa. Salami is usually sliced thin for use in sandwiches or, in the case of pepperoni, on pizza. One slice of cooked salami (23 g) yields 57.5 calories; fat, 4.5 g; protein, 3 g; potassium, 45.5 mg; sodium 245 mg. saliva The fluid secreted by glands of the MOUTH. Three pairs of salivary glands produce saliva. Parotid glands, located on each side of the face, drain through ducts opening in the inner surface of the cheek. Sublingual glands drain into the floor of the mouth. Submaxillary glands (submandibular glands) are located beneath the base of the tongue and drain in the floor of the mouth. Tiny buccal glands in the mouth also contribute saliva. The combined saliva from all these sources amounts to a quart (1 liter) of fluid daily. In composition, saliva is 99.5 percent water. Saliva serves important functions: It acts as a lubri- cant, as a moistening agent and as a dissolving agent for flavors as food is chewed and swallowed. Saliva contains mucins, slippery PROTEINS that pro- vide the lubricating action. Without water and mucins, swallowing would be very difficult. Saliva contains the digestive enzyme AMYLASE, which ini- tiates starch DIGESTION, and chewing food thor- oughly to a uniform paste assists starch breakdown by this enzyme. Saliva also contains ions (elec- trolytes)— SODIUM, CHLORIDE, and BICARBONATE. Chloride activates amylase. These minerals are later absorbed and recycled. For defense, saliva contains lysozyme, an enzyme that ruptures some disease-producing bacteria, and a protective ANTI- BODY, secretory IgA, that can bind to foreign mate- rials, including viruses, bacteria, and yeast, to reduce this risk of infection. Salivation is controlled exclusively by the NER- VOUS SYSTEM. Savory aromas, visual images, sounds of food preparation, and memories can stimulate salivation. Salivation also occurs in response to irri- tating foods and with nausea. Saliva flow after eat- ing flushes chemical remnants out of the mouth and adjusts the acidity to neutral. Dehydration can decrease salivation. A variety of medications, such as antihistamines (diphenylpyraline and azatidine), diminish mucous secretions, including saliva. Stress stimulates the sympathetic nervous system to reduce salivation. On the other hand, dryness of the mouth promotes thirst sensations. (See also DEGLUTITION; TASTE.) salmon (Oncorhynchus) A saltwater fish valued as a food fish, and as a sport fish. The word salmon is derived from the Latin salmo, which means “leap- ing.” Salmon can weigh up to 65 lb. and measure up to 3 ft. long. Varieties include the Atlantic salmon and the five varieties of Pacific salmon: sockeye (red) salmon (O. nerka), both canned and sold fresh; Chinook (king) salmon (O. tschawytscha), the largest and fattiest variety; coho (sliver) salmon (O. kisutch), smaller fish, sold fresh; pink (hump- back) salmon (O. gorbuscha), the smallest variety, bland flesh, sold canned; and chum (dog) salmon (O. keta), lower in fat and with pale flesh. Salmon are a migratory fish that spawn in fresh water. Young fish live in fresh water for two years before migrating to the sea. Pollution, dam construction, and overharvesting have drastically reduced the numbers of this food fish in many parts of the world. Commercial salmon comes from many countries, such as Chile, Norway, and Canada (eastern Canada and British Columbia). Imported salmon are generally pen-raised rather than wild fish. Domestic, pen-raised salmon are also readily available. In the United States, Maine, Alaska, and Washington support most major salmon fisheries, and canned salmon comes from the northern Pacific. Most Atlantic salmon comes from Canada and Norway. salmon 567 Salmon is an oily fish, rich in beneficial marine lipids. Salmon fat contains 30 percent to 40 percent omega-3 polyunsaturated FATTY ACIDS, mainly EPA ( EICOSAPENTAENOIC ACID) and DHA (DOCASAHEXA- ENOIC ACID ). These polyunsaturates are believed to decrease the risk of STROKE and CARDIOVASCULAR DISEASE . They decrease the risk of blood clots by inhibiting blood platelet aggregation. Platelets are cell fragments in the blood that initiate clotting. Pen-raised salmon are more likely to be conta- minated with industrial pollutants when grown in waters near industrial areas. Consumer advocates have criticized seafood safety in the United States. PCB contamination has been detected in fresh salmon although the levels were below tolerance limits set by the U.S. FDA. Canned salmon sold in the United States comes from the Pacific off the coast of Alaska, an area less likely to be polluted by industrial waste. Salmon is smoked, poached, grilled, marinated, baked, or canned. The nutrient content of 3 oz. (85 g) of broiled salmon is: 140 calories; protein, 21 g; fat, 5 g; cholesterol, 60 mg; thiamin, 0.18 mg; riboflavin, 0.14 mg; niacin, 5.5 g. (See also FISH OIL; OMEGA-3 FATTY ACIDS; SEAFOOD.) salmonella A bacterium that includes more than 1,300 strains that frequently causes FOOD POISON- ING. Salmonella does not form spores and is destroyed by heat. Its usual habitat is the intestinal tract of an animal host. Salmonella occurs in ani- mal feed, food processing plants, and food han- dling, and the bacteria are easily spread by fecal contamination. Flies, rodents, and insects that con- tact infected fecal material may also contaminate food. Sewage-contaminated water is known to carry salmonella and cause disease. Livestock and poultry are major sources of human infection. About one in 20,000 eggs is con- taminated. Thoroughly cooking eggs destroys the bacteria. According to the U.S. Centers for Disease Control and Prevention, most cases of salmonella poisoning are caused by eating undercooked eggs in sauces, salads, and processed foods. Salmonella grows readily in milk and milk-derived dishes such as custard, egg dishes, and salad dressing. MEAT and meat products like SAUSAGE, meat pies, sandwiches, and chili can become contaminated when allowed to stand at room temperature for several hours if infected by a food handler. salmonellosis A form of food poisoning caused by salmonella. Salmonellosis is one of the three most common food-borne diseases associated with bacteria, and it is one of the fastest growing food- borne illnesses. Every year about 40,000 cases of salmonellosis are reported in the United States. The actual number of cases may be much higher because many people who have been infected do not seek professional care and are therefore not diagnosed and reported. Illness caused by salmo- nella is more common during the summer months, and children are more likely to be infected. Salmo- nellosis can be fatal, especially in young children, the immunocompromised, and elderly people. About 1,000 persons die each year from acute sal- monellosis. Some strains of salmonella resist antibi- otics, and dairy cattle fed antibiotics were the likely source of a drug-resistant salmonella strain that caused a large U.S. outbreak of food poisoning, involved six states in 1985. This outbreak caused 1,000 deaths, 35,000 hospitalizations and left an estimated 125,000 people with increased risk of chronic illnesses such as ARTHRITIS, osteomyelitis, ankylosing spondylitis, and COLITIS. Salmonellosis often causes flu-like symptoms. Fever, abdominal cramping, headache, DIARRHEA , and vomiting generally appear 12 to 36 hours after eating tainted food. Symptoms may last from two days to a week. Illness is most severe in those with weakened immune systems, commonly found in very young children and in elderly people. Maldigestion and MALABSORPTION can result from intestinal damage due to this disease. Salmonellosis was almost unknown in the United States 40 years ago. Increased volume and speed of food production, increased drug resistance of bacteria, and relaxed enforcement by govern- ment agencies contributed to widespread contami- nation of food, especially POULTRY. Raw milk, raw cheese, any raw or undercooked meat, including salami and hamburger, and fresh eggs can be cont- aminated by feces and fecal bacteria and can thus be a potential source of contamination. Pasteurized eggs are used to prepare commercial MAYONNAISE, and it is not a carrier. Freshwater as well as marine fish caught from waters highly polluted by raw sewage may be contaminated by salmonella. All food handlers should thoroughly wash their hands before handling food to eliminate fecal con- 568 salmonella tamination. They should carefully clean all equip- ment used in food preparation, including cutting boards. Raw vegetables should not come into con- tact with utensils used to prepare raw meat and poultry. Food should be refrigerated. Salmonella is destroyed by heating at 140° F (60° C) for 20 min- utes or at 149° F (60° C) for three minutes. (See also BOTULISM.) Olsen, S. J. et al. “The Changing Epidemiology of Salmo- nella: Trends in Serotypes Isolated from Humans in the U.S., 1987–1997,” Journal of Infectious Diseases 183 (2000): 756–761. salt See SODIUM. salt substitutes (potassium chloride, lite salt, low- sodium salt) A combination of chemicals that taste like table salt but contains less SODIUM. Exces- sive salt in the diet can cause HIGH BLOOD PRESSURE in hypertensive people who are sodium sensitive. Most salt substitutes are mixtures of table salt (sodium chloride) and POTASSIUM chloride. Potas- sium is an essential nutrient in its own right and can lower blood pressure in some people. Excessive potassium can irritate the stomach and might start an ulcer. Diseased or damaged kidneys may not be able to excrete potassium properly; a toxic excess can accumulate. Therefore, patients taking certain DIURETICS (water pills), beta blockers or non- steroidal anti-inflammatory drugs; who are dia- betic; or who have kidney disease are advised to avoid such salt substitutes. The safest strategy is to cut back on salt entirely and to use herbs and spices to improve the flavor in place of table salt. There are many different herbs to choose from, each with its own different, pleasing flavor. Consider CAYENNE pepper, basil, garlic powder, mace, marjoram, SAGE, savory and thyme, or blends. (See also FOOD ADDI- TIVES; HYPERTENSION.) salt tablets See SODIUM. SAMe See S-ADENOSYLMETHIONINE. sardine Various small saltwater fish, including alewife, Atlantic HERRING, pilchard, and sprat. The name probably originated from the small Mediter- ranean fish in the vicinity of the island of Sardinia. Sardines are a fatty fish. Atlantic herring is a good source of OMEGA-3 FATTY ACIDS, the essential fatty acids thought to protect against heart attacks. Sardines are rich sources of calcium because the fish is cooked bones and all. Its soft bones con- tribute to a high calcium content. A 4 oz. serving of sardines provides 50 percent of the REFERENCE DAILY INTAKE (RDI) of calcium and 20 percent of the RDI or iron. Sardines contain significant levels of salt. The same 4 oz. serving provides approximately 600 mg of sodium, one-third to one-half of the amount judged safe. Sardines are often packed in oil, which increases their calories. Sardines packed in olive oil would be preferable to those packed in soybean oil because of olive oil’s greater stability and protective effects against heart disease. Norwegian sardines are often packed in sardine oil, which has a high content of omega-3 fatty acids. Blot the fish in oil with a paper towel before eating them, to remove excess oil and to lower calories. Sardines packed in water are now available. The nutrient content of 3 oz. (85 g) of sardines (canned, packed in soybean oil, drained, and including bones) is: 175 calories; protein, 20 g; fat, 9.4 g; cholesterol, 85 mg; calcium, 371 mg; iron, 2.6 mg; thiamin, 0.03 mg; riboflavin, 0.17 mg; niacin, 4.6 mg. sarsaparilla (Smilax sarsaparilla) A medicinal herb native to tropical regions of South America and the Caribbean. This perennial evergreen grows as a vine; its roots are used in botanical medicine. Europeans learned of its use from Native Ameri- cans. According to folk traditions, sarsaparilla has been used as a tonic (to improve body function) and in the treatment of coughs, digestive disorders, fever, gout, skin conditions, and arthritis. Exter- nally it has been used for burns and wounds. No toxicity has been reported, though the effects of long-term, high-level consumption are unknown. Sarsaparilla contains a family of saponins, steroid-like molecules that appear to bind cell wall materials released by bacteria in the intestine. Endotoxins can be absorbed by the gut and pass into the bloodstream unless removed by the liver. By rendering endotoxins unabsorbable, sarsaparilla may improve liver function and decrease the bur- den of foreign materials. The plant does not contain sarsaparilla 569 testosterone, the male hormone, and does not increase muscle mass. Thus, there is little evidence to support the contention that sarsaparilla acts as a sexual rejuvenator. Sarsaparilla extracts have been routinely used to flavor beverages, candy, baked goods, and other foods. satiety The sense of being filled up and having APPETITE satisfied, as opposed to HUNGER. Appetite is a complex phenomenon involving many psycho- logical and biochemical factors. No single event is likely to control it. Fat and oils in foods slow emp- tying of the stomach and contribute to the feeling of being full. Researchers are exploring the hypoth- esis that depleted fat cells may signal the brain to eat and cause hunger after weight loss. LEPTIN,a recently discovered protein produced by fat cells, has been shown to enter the brain and control the consumption of fatty foods. Dietary FIBER, undi- gestible plant material, swells when moistened, creating a feeling of fullness. As a further benefit, fiber displaces calorie-rich foods, so fewer calories are eaten. Mechanical contact with food triggers the stom- ach and intestine to release gut peptides that trigger satiety. This feedback mechanism requires 10 to 20 minutes, while signals are being sent back to the brain. As an example, the hormone CHOLECYS - TOKININ signals the brain to stop sending hunger sig- nals after eating. Whether cholecystokinin can be manipulated by dietary changes is not known for certain. Brain peptides are also probably involved in regulatory food consumption and satiety. Entero- statin decreases fat intake in experimental animals. The development of drugs to increase satiety is cur- rently an area of active research. Strategies to pro- mote a feeling of satiation and to curb appetite include eating a snack a half-hour before a meal, eating slowly and chewing each bite thoroughly and waiting 20 minutes before taking a second helping. These approaches give the hormone time to reach the brain and create a feeling of fullness. (See also APPETITE SUPPRESSANTS; CRAVING.) saturated fat FAT that contains a high percentage of saturated FATTY ACIDS and exists as a solid at room temperature. Saturation is a chemical con- cept, referring to the fact that carbon atoms in the fatty acid molecules are bonded to a maximum number of hydrogen atoms (“filled up”). Typical sources of saturated fat are animal fat, as found in BEEF , veal, LAMB, PORK, meat products, MILK, EGGS, BUTTER, and products like ICE CREAM, milk, and CHOCOLATE . Certain plant oils are also saturated, including COCONUT OIL, PALM, and palm kernel oils. Unsaturated fat (vegetable oils) can be converted to saturated fats by a chemical process called hydro- genation, and these appear on the market as veg- etable shortening. Saturated Fatty Acids Common building blocks of fats and oils, these organic acids contain a maximum number of hydrogen atoms and lack double bonds. Fatty acids are built of carbon chains, which may be long or short. Long-chain, saturated fatty acids include PALMITIC ACID (16 carbon atoms) and STEARIC ACID (18 carbon atoms). They are waxy solids at room temperature and can form fats that are also solids at room temperature. Typical short-chain saturated fatty acids include: acetic acid (containing two car- bon atoms), propionic acid (with three carbon atoms), and BUTYRIC ACID (four carbon atoms). Medium-chain fatty acids include CAPRYLIC ACID (with eight carbons); capric acid (10 carbons); lau- ric acid (12 carbons); and myristic acid (14 carbons). All saturated fatty acids are readily oxidized by mitochondrial enzyme systems to produce energy with carbon dioxide and water as waste products. Fatty acids yield more than twice the amount of energy as carbohydrate and protein when they are burned. (See also ESSENTIAL FATTY ACIDS.) saturated vegetable oils See TROPICAL OILS. sauce A flavorful relish or liquid dressing served with foods. Sauces are usually high- FAT foods. Stroganoff and orloff usually contain butter. Hol- landaise and bearnaise sauces contain butter and egg yolks; bearnaise contains undercooked raw egg yolk and so is a potential source of food poisoning. MAYONNAISE contains egg yolks, VINEGAR, and a veg- etable oil. Brown sauces (bordelaise and bour- guignon) may be lower in fat if fat has been skimmed off and if butter has not been added. Tar- tar sauce and remoulade are flavored mayonnaise. 570 satiety sauerkraut Fermented white CABBAGE. Cabbage is pickled in salt, spices, and cabbage juice by lactic acid-producing bacteria. The lactic acid gives sauer- kraut its characteristic sour flavor. Canned sauer- kraut also has a very high sodium level (up to 780 mg per half-cup). It can be strained and rinsed to decrease the sodium content. Dill seed and onion can be used to enhance the flavor of sauerkraut. (See also FERMENTATION; FOOD PRESERVATION .) sausage A seasoned, ground meat product usu- ally containing high levels of SODIUM and FAT and packed in a casing. The term sausage is derived from the Latin salsicius, meaning “seasoned with salt.” Most sausage contains highly seasoned, finely ground beef and pork and table salt. Any meat from a USDA-inspected carcass can be used to make sausage and animal fat can be added. Thus, blood sausage is made from blood, pork fat, and season- ing. The final product may be cured (smoked) and dry or semidry. Dry and semidry sausage may con- tain NITRITES as preservatives, which have been linked to an increased risk of stomach cancer if con- sumed in large amounts. Fresh sausage is made from raw meat and must be cooked. Semidry sausage has been smoked; dry sausage may or may not be smoked; and cooked sausage is ready to eat. Examples include BOLOGNA, braunschweiger, frank- furter, head cheese, knackwurst, LIVERWURST, salami, souse, and Vienna sausage. Sausages contain ample protein, iron, and many B vitamins; however, they also contain almost 55 percent of their calories as fat. A few brands con- tain less than 40 percent of their calories as fat. Tofu and turkey sausage may contain less fat than pork or beef products. It is recommended that sausage be eaten as a condiment or flavoring with foods rather than as a main dish. Pork sausage, cooked, can provide 72 percent of calories as fat; fat accounts for 31 percent of the weight. One link, 13 g, provides 50 calories; pro- tein, 2.5 g; carbohydrate, 0.1 g; fat, 4 g; cholesterol, 11 mg; sodium, 168 mg; thiamin, 0.1 mg; ribo- flavin, 0.03 mg; niacin, 0.59 mg. (See also CHICKEN; MEAT, PROCESSED; MEAT SUBSTITUTES; POULTRY.) sauté Refers to pan frying small strips or slices of food quickly in a hot skillet with a small amount of butter or oil. Be sure oil is hot before adding foods to minimize the amounts of oil they soak up. Pork slices, veal scallops, chicken breast, fish fillet, tofu, onions, carrots, garlic, and other vegetables and grains can be sauteed. saw palmetto (Serenoa repens) A small palm tree native to South Carolina, Georgia, and Florida that produces berries with medicinal properties. Saw palmetto berries have a long history of use by Native Americans, while later European physicians used the berries to treat enlarged prostate (benign prostatic hyperplasia), genitourinary tract imbal- ances, and as a tonic to boost nutrient and general body functioning. Modern formulations employ a fat-soluble extract of saw palmetto berries contain- ing large-molecular-weight alcohols and plant sterols, compounds related to cholesterol. Saw pal- metto berry extracts block the conversion of the male sex hormone, testosterone, to a more potent compound, dehydrotesterone, that promotes pro- static enlargement, and promote the breakdown of the more active compound. These effects may pos- sibly explain the saw palmetto relief of common symptoms such as decreased urination at night, increased urinary flow rates, and decreased resid- ual urine content in the bladder. No significant side effects of saw palmetto berry extracts or berries have been noted. School Breakfast Program A federal program to provide funds for nutritious breakfasts for chil- dren. The National School Breakfast Program was established by the Child Nutrition Act of 1966 an authorized as a permanent appropriation in 1975. Fewer children participate in the BREAKFAST pro- gram than in the SCHOOL LUNCH PROGRAM. In the 1999–2000 school year 7.6 million children partic- ipated in the breakfast program, while 27.4 million children participated in the lunch program. Usu- ally a state’s Department of Education administers this program. The school breakfast must contain one serving of meat or meat alternative (such as eggs or peanut butter), two or more servings of different fruits or vegetables, and one serving of milk. Factors weighed in planning school food service programs include: cultural and ethnic backgrounds School Breakfast Program 571 of students, needs of handicapped students, as well as fitting meals to accommodate class and bus schedules. Practical nutrition education can be part of breakfast programs. Evaluation of school nutri- tion programs finds that most students participat- ing in school breakfast programs are from low-income families. Breakfast is considered the most important meal for both children and adults because of its positive impact on performance and alertness. Nonetheless, many Americans skip breakfast, especially teen- agers. Students who skip breakfast have higher rates of tardiness, higher absenteeism and lower performance, and more FATIGUE . Researchers shows that low-income children who participate in the School Breakfast Program have higher stan- dardized achievement test scores than children not in the program. (See also HUNGER; WIC.) School Lunch Program A federal program estab- lished under the National School Lunch Program of 1946 to protect the health of U.S. children through the consumption of nutritious foods. The act authorized state grant-in-aid program to provide cash and food. The cost is shared among the USDA, state and local governments, and children’s fami- lies. Household income determines whether a child will receive a reduced rate or free meal. To qualify, household income must be below 185 percent of the federal poverty level; for free meals household income must fall below 130 percent of the poverty level. The National School Lunch Program is open to public and private schools and to residential child care institutions. Schools that participate in the program receive financial assistance, donated sur- plus commodities and technical assistance in equipping and managing the program. In the 1970s, the Nutrition Education and Training Pro- gram was developed to educate students about the relationship between nutrition and health, to train food service personnel in management, and to instruct teachers in nutrition education. The pro- gram was expanded due to increased need for low-cost, subsidized meals, especially among eco- nomically disadvantaged children. On a typical day in school year 2000–2001, 15.6 million children participated in the program. The program has continued to serve nutritious school lunches to children who would not likely receive lunch from another source. Furthermore, school lunches have provided approximately 33 percent of the RECOMMENDED DIETARY ALLOWANCES (RDAs) for children of various ages. Eligibility for participation in the program is contingent upon operating on a nonprofit basis, providing free or reduced price lunches to needy children, making lunches available to all children providing dining and kitchen facilities, avoiding segregation of needy children and serving meals that conform to USDA guidelines. School lunches must meet the DIETARY GUIDE- LINES FOR AMERICANS, which recommend that no more than 30 percent of a person’s calories come from fat and less than 10 percent from saturated fat. The lunches should also provide one-third of the U.S. RDA of protein, iron, calcium, and vita- mins A and C. In 2001 the Physician’s Committee for Responsible Medicine issued a report that found that many school lunches offered in the National School Lunch Program did not meet these require- ments. Only one in 12 elementary school districts substituted lower-fat, cholesterol-free plant protein in place of meat, and one-fourth were not meeting USDA nutrition requirements. scromboid fish poisoning A type of FOOD POISON- ING that occurs within an hour after eating species of spoiled fish that populate tropical oceans, includ- ing TUNA, MACKEREL, skipjack, BONITO, HERRING, mahi-mahi, SARDINES, and anchovies. An impor- tant clue to contamination is that infected fish taste metallic and peppery. Symptoms of poisoning in- clude flushing, sweating, nausea, vomiting, diar- rhea, headache, and dizziness. Antihistamines relieve the symptoms. Scromboid fish poisoning can be prevented by keeping fresh fish on ice or refrigerated until it is cooked. (See also FOOD TOXINS .) scurvy A disease caused by severe deficiency of VITAMIN C (ascorbic acid). Scurvy has been de- scribed since ancient times. Long sea voyages of the 15th through the 17th centuries frequently deci- mated the ranks of sailors. As early as 1593, a British admiral demonstrated that lemon juice 572 School Lunch Program cured the disease. A Scottish naval surgeon con- ducted the first controlled experiment in the treat- ment of scurvy in 1753, which proved that citrus fruits protected seamen and cured scurvy. Not until 40 years later were limes routinely issued to British seamen to prevent scurvy. However, scurvy continued into more recent times. It was prevalent during the American Civil War, and in 1912 half the men on Scott’s expedition to the South Pole died of scurvy. During initial stages of vitamin C deficiency, an individual may feel listless. Wounds may heal slowly and gums may bleed easily. Bruising occurs easily. Minute hemorrhages appear around hair follicles or stomach, buttocks, legs, and arms. Later stages are characterized by weight loss, weakness, painful muscles, swollen joints, spongy gums, and loss of teeth. Vitamin C plays several important roles that can be related to scurvy. Chief among these is the requirement for vitamin C in COLLAGEN. The formation of mature collagen, the major struc- tural protein of connective tissue, relies on the availability of key building blocks called hydrox- yproline and hydroxylysine. The production of hydroxyproline from proline and of hydroxyl lysine from lysine requires vitamin C. As a versatile antioxidant and key support nutrient of the immune system, vitamin C exhibits wide-ranging benefits on health. Modest deficiencies do not manifest themselves as scurvy, rather they increase the susceptibility to infections and oxidative dam- age leading to chronic diseases. Infants relying on cow’s milk may be prone to scurvy because much of the vitamin C is destroyed during pasteurization. Infants require proportion- ately higher levels of vitamin C because of their high rate of tissue growth. Breast milk contains adequate vitamin C to support infant develop- ment. Among adults, low-income elderly persons are susceptible to scurvy if they do not eat fresh fruit and vegetables. Overcooking destroys most vitamin C in vegetables. Chronic disease, injuries, and surgery are more likely in this group, and these conditions deplete the body stores of this vitamin. (See also MALNUTRITION.) Rajakumar, Kumaravel. “Infantile Scurvy: A Historical Perspective,” Pediatrics 108, no. 4 (2001): e76. seafood Edible marine fish and shellfish such as CLAMS, mussels, scallops, OYSTERS, LOBSTERS, and SHRIMP that represent an important, highly nutri- tious food source. It is low in saturated fat and calo- ries and is a good source of PROTEIN, IRON, VITAMIN B 12 , IODINE, PHOSPHORUS, ZINC, and COPPER. Fish and fish oil are particularly rich in the omega-3 family of polyunsaturated FATTY ACIDS , which help reduce INFLAMMATION in conditions like ARTHRITIS and pso- riasis, as well as reducing the risk of blood clot for- mation, thus offering protection against HEART ATTACKS . COD LIVER OIL contains high levels of VITA- MIN A and VITAMIN D, which may be toxic when consumed in large amounts. Several servings per week of the following fatty fish are recommended: bluefish, butterfish, halibut, herring, mackerel, striped bass, orange roughy, smelt, salmon, sar- dines, trout, and pompano. The larva of parasitic worms may contaminate raw fish, including Pacific salmon, Pacific red snap- per (rockfish), and herring; thus raw fish dishes (sushi, sashimi, CEVICHE, lomi-lomi) carry a risk of parasitic disease, such as anisakiasis. Inadequately smoked or salted fish can carry parasites. The severe abdominal pain of such a disease is due to acute intestinal inflammation. The parasite is killed by cooking marine fish thoroughly. Pregnant and nursing women, very young children, and elderly people should avoid raw fish and shellfish to mini- mize this risk. Chemical Contamination Chemical contaminants are another prominent issue in seafood safety. Fish and shellfish are gen- erally more susceptible to chemical contamination than meat and poultry because they filter huge amounts of water through their bodies and feed on other organisms in which contaminants may be concentrated. Clams and oysters can filter 15 to 20 gallons of water daily. While thorough cooking destroys parasites and microorganisms, this does not eliminate chemical pollutants like LEAD, chlor- dane, DIOXIN, DDT, MERCURY, PBBs, and PCBs. Such industrial chemicals were once widely used in PES- TICIDES, electrical insulation, plastics, dyes, and other products. Over decades these environmental pollutants have crept into the FOOD CHAIN because they are not readily broken down and because they tend to accumulate in plants and animals. seafood 573 Varying levels of pollutants have been reported in both domestic and imported fish. While levels of detected pollutants have generally fallen below FDA tolerance limits, those limits were set when fish consumption was lower and consequently people accumulated less of these pollutants. The level of pollutant can vary with the source, but in many markets it is often difficult for the consumer to determine the source of fish sold. Pollutant lev- els in salmon from Pacific waters may be lower than from other sources; however, the fish the con- sumer buys may come from Chile, Norway, Eastern Canada, Maine, as well as from Washington, Alaska, or British Columbia. Chemical pollutants may increase the risk of certain cancers, birth defects, and neurological damage in unborn children. However, the potential health hazards of long-term, very low-level expo- sure remain unknown. Because residue buildup occurs over years, it may be hard to trace a disease cause to a specific pollutant exposure. Shellfish can accumulate disease-causing bacte- ria and viruses when exposed to untreated sewage. Harvesting is limited to waters that are certified as being clean, although enforcing the policy is limited by resources. Eating raw shellfish carries the risk of gastrointestinal disease with symptoms such as diar- rhea, cramps, nausea, and vomiting. Shellfish also transmit hepatitis A virus. Well-cooked shellfish are safer than raw or semi-cooked shellfish. To ensure that seafood is as safe to eat as possi- ble, consumers should • Buy fresh seafood. Fish and shellfish spoil easily and should be handled with care. Fresh fish should have a mild “ocean” smell; they should not smell “fishy” or smell like ammonia. • Fresh seafood should be bought from reputable merchants who can identify their source. • Seafood should be refrigerated at home immedi- ately after purchase to prevent bacterial growth, minimize spoilage, and reduce the risk of FOOD POISONING . Raw seafood that will not be eaten within two days should be frozen. Most shrimp have been frozen and thawed, and should be cooked as soon as possible. • Frozen seafood should be thawed in the refrig- erator or in cold running water and not refrozen. Other raw shellfish, including lobster, should be alive when purchased. • Cooked shellfish should be refrigerated and used on the same day. • Mussels, clams, and oysters should be moistened and refrigerated to keep them alive rather than stored in plastic bags. They should not be stored for a long time in fresh water. • Any shellfish that remains closed after steaming should be discarded. Raw shellfish that remain closed are dead and may have begun to decom- pose. • Consumers should follow the same rules in han- dling raw seafood as when handling raw poultry and raw meat to avoid contaminating cooked dishes or fresh vegetables with bacteria: Wash with soap and water all utensils, countertops, cutting boards and hands that have come into contact with raw seafood. • Consumers should eat a variety of seafoods rather than a single source to minimize overex- posure to pollutants. Elderly people, young children, pregnant women, patients with com- promised immune systems or with liver disease should avoid eating raw seafood. Connor, W. E. “Importance of n-3 Fatty Acids in Health and Disease,” American Journal of Clinical Nutrition 71 (2000): 171S–175S. seafood inspection Fish and shellfish are among the most perishable foods, yet seafood is one of the least regulated foods; it remains the only flesh that does not undergo mandatory inspection. In con- trast, meat and poultry processing facilities are inspected daily. A single-time FDA inspection of most U.S. seafood processing plants revealed a rel- atively low violation rate of up to 5.1 percent of plants, depending on the region. An estimated 20 percent of food-borne illness is caused by seafood. Seafood can be contaminated by bacteria, viruses, parasites, and industrial wastes and pollutants. While the National Academy of Sci- ences has concluded that most seafood is safe to eat, this advisory organization has also recom- mended increased inspection and regulation of the industry. Fish testing in specific areas is left to state agencies, and testing for chemical contaminants 574 seafood inspection [...]... abnormal elastic tissue The first line of IMMUNE SYSTEM defense in the skin are Langerhans cells These sentries can detect the intrusion of foreign materials and quickly signal other components of the immune system to counterattack U.V light whether from tanning parlors or from sunlight suppresses these cells Photosensitivity can aggravate the reaction to the sun s rays Certain foods (citrus fruits, for... soybeans are the leading U .S cash crop, ahead of WHEAT and CORN, and the United States is the world s major supplier of soybeans Illinois, Iowa, Missouri, Minnesota, and Ohio are among the top producers of soybeans, which represent the largest domestic source of VEGETABLE OIL Dried soybeans can be cooked like dried beans and served in salads or casseroles Roasted soybeans are a high-fat snack food Soybeans... world starch The storage carbohydrate that occurs in granules in seeds, stems, and roots of higher plants Starch consists of long chains of GLUCOSE, a simple sugar, formed during PHOTOSYNTHESIS Starch accounts for 50 percent to 75 percent of the weight of cereal GRAIN and 75 percent of the weight of POTATOES Unripened apples and bananas contain starch; as these fruits ripen, much of the starch is converted... set point shellfish See DIETING; WEIGHT MANAGEMENT Mollusks and crustaceans that have been long used as food sources Univalve mollusks such as abalone are enclosed in a single shell; bivalve mollusks with a two-part shell include mussels, OYSTERS, and scallops Cephalopods (creatures with tentacles, like squid) are a type of mollusk Crustaceans, which possess a tough outer layer and segmented bodies... “Meta-analysis of the Effects of Soy Protein Intake on Serum Lipids,” New England Journal of Medicine 333 (August 3, 1995): 276–282 soy milk soy sauce See SOYBEAN See SOYBEAN spastic colon See IRRITABLE BOWEL SYNDROME specific dynamic effect (SDE; specific dynamic activity, SDA) The ENERGY used by the body to digest and process foods The secretion of ENZYMES and HORMONES and the uptake of nutrients by the. .. with other amino acids According to this hypothesis, as the level of tryptophan rises in the brain, more serotonin is synthesized, leading to relaxation and decreased alertness (See also NERVOUS SYSTEM.) serum The clear, straw-colored fluid remaining after blood has clotted Serum contains CHOLESTEROL (serum cholesterol) in the form of LOW-DENSITY LIPOPROTEIN (LDL, the less desirable form) and HIGH-DENSITY... compared to the rate from eating the sugar alone Processed starches such as white bread, white rice, and instant mashed potatoes send blood glucose soaring almost as fast as sugar does On the other hand, starch in whole foods like legumes is more slowly digested and does not cause a surge of blood sugar Consequently, the pancreas does not need to release such a large amount of the hormone INSULIN to stimulate... Pacific coasts and G tamarensis in the Bay of Fundy and in the St CLAMS 580 sherbet Lawrence estuary on the North Atlantic Symptoms begin with numbness in lips and tongue, spreading to arms and legs and respiratory distress Red tide can cause blood poisoning and death in high-risk individuals—patients with liver disease, AIDS, or alcoholics Mussels gradually destroy or eliminate bound poisons after an... upon the hardness of natural water A glass of tap water usually contains less than 3 mg of sodium However, salt from the de-icing of roads and ion exchange resins can raise sodium levels in inland areas Sodium from seawater can leach into the water supplies of coastal areas Requirements There is no RECOMMENDED DIETARY ALLOWANCE (RDA) for sodium A safe and adequate level was proposed by the Food and Nutrition. .. glucose syrup The artificial sweetener ASPARTAME is used extensively in diet soft drinks SACCHARIN, another noncaloric sweetener, is used in soft drinks as well Phosphoric acid is added to acidify soft drinks Other acids used in soft drinks include ACETIC ACID, fumaric acid, LACTIC ACID, and gluconic acid, an acid of glucose The phosphate in soft drinks increases the overall phosphate consumption This . Well-cooked shellfish are safer than raw or semi-cooked shellfish. To ensure that seafood is as safe to eat as possi- ble, consumers should • Buy fresh seafood. Fish and shellfish spoil easily and should. food handler. salmonellosis A form of food poisoning caused by salmonella. Salmonellosis is one of the three most common food-borne diseases associated with bacteria, and it is one of the fastest. limited by resources. Eating raw shellfish carries the risk of gastrointestinal disease with symptoms such as diar- rhea, cramps, nausea, and vomiting. Shellfish also transmit hepatitis A virus. Well-cooked

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