Nutritional Profile Energy value (calories per serving): Moderate Protein: High Fat: Moderate Saturated fat: High Cholesterol: Moderate Carbohydrates: None Fiber: None Sodium: Low Major vitamin contribution: B vitamins Major mineral contribution: Iron, phosphorus, zinc
About the Nutrients in This Food Like fish, pork, poultry, milk, and eggs, beef has high-quality proteins, with sufficient amounts of all the essential amino acids. Beef fat is slightly more highly saturated than pork fat, but less saturated than lamb fat. All have about the same amount of cholesterol per serving. Beef is an excellent source of B vitamins, including niacin, vitamin B6, and vitamin B12, which is found only in animal foods. Lean beef pro- vides heme iron, the organic iron that is about five times more useful to the body than nonheme iron, the inorganic form of iron found in plant foods. Beef is also an excellent source of zinc. One four-ounce serving of lean broiled sirloin steak has nine grams fat (3.5 g saturated fat), 101 mg cholesterol, 34 g protein, and 3.81 mg iron (21 percent of the R DA for a woman, 46 percent of the R DA for a man). One four-ounce serving of lean roast beef has 16 g fat (6.6 g saturated fat), 92 mg cholesterol, and 2.96 mg iron (16 percent of the R DA for a woman, 37 percent of the R DA for a man).
The Most Nutritious Way to Serve This Food With a food rich in vitamin C. Ascorbic acid increases the absorption of iron from meat. * These values apply to lean cooked beef.
Diets That May Restrict or Exclude This Food Controlled-fat, low-cholesterol diet Low-protein diet (for some forms of kidney disease)
Buying This Food Look for: Fresh, red beef. The fat should be white, not yellow. Choose lean cuts of beef with as little internal marbling (streaks of fat) as possible. The leanest cuts are flank steak and round steak; rib steaks, brisket, and chuck have the most fat. USDA grading, which is determined by the maturity of the animal and marbling in meat, is also a guide to fat content. U.S. prime has more marbling than U.S. choice, which has more marbling than U.S. good. All are equally nutritious; the difference is how tender they are, which depends on how much fat is present. Choose the cut of meat that is right for your recipe. Generally, the cuts from the cen- ter of the animal’s back—the rib, the T-Bone, the porterhouse steaks—are the most tender. They can be cooked by dry heat—broiling, roasting, pan-frying. Cuts from around the legs, the underbelly, and the neck—the shank, the brisket, the round—contain muscles used for movement. They must be tenderized by stewing or boiling, the long, moist cooking methods that break down the connective tissue that makes meat tough.
Storing This Food Refrigerate raw beef immediately, carefully wrapped to prevent its drippings from contami- nating other foods. Refrigeration prolongs the freshness of beef by slowing the natural multi- plication of bacteria on the meat surface. Unchecked, these bacteria will convert proteins and other substances on the surface of the meat to a slimy film and change meat’s sulfur-contain- ing amino acids methionine and cystine into smelly chemicals called mercaptans. When the mercaptans combine with myoglobin, they produce the greenish pigment that gives spoiled meat its characteristic unpleasant appearance. Fresh ground beef, with many surfaces where bacteria can live, should be used within 24 to 48 hours. Other cuts of beef may stay fresh in the refrigerator for three to five days.
Preparing This Food Trim the beef carefully. By judiciously cutting away all visible fat you can significantly reduce the amount of fat and cholesterol in each serving. When you are done, clean all utensils thoroughly with soap and hot water. Wash your cutting board, wood or plastic, with hot water, soap, and a bleach-and-water solution. For ultimate safety in preventing the transfer of microorganisms from the raw meat to other foods, keep one cutting board exclusively for raw meats, fish, and poultry, and a second one for everything else. Finally, don’t forget to wash your hands.
What Happens When You Cook This Food Cooking changes the appearance and flavor of beef, alters nutritional value, makes it safer, and extends its shelf life. Browning meat after you cook it does not “seal in the juices,” but it does change the fla- vor by caramelizing sugars on the surface. Because beef’s only sugars are the small amounts of glycogen in the muscles, we add sugars in marinades or basting liquids that may also con- tain acids (vinegar, lemon juice, wine) to break down muscle fibers and tenderize the meat. (Browning has one minor nutritional drawback. It breaks amino acids on the surface of the meat into smaller compounds that are no longer useful proteins.) When beef is cooked, it loses water and shrinks. Its pigments, which combine with oxygen, are denatured (broken into fragments) by the heat and turn brown, the natural color of well-done meat. At the same time, the fats in the beef are oxidized. Oxidized fats, whether formed in cooking or when the cooked meat is stored in the refrigerator, give cooked meat a character- istic warmed-over flavor. Cooking and storing meat under a blanket of antioxidants—catsup or a gravy made of tomatoes, peppers, and other vitamin C-rich vegetables—reduces the oxidation of fats and the intensity of warmed-over flavor. Meat reheated in a microwave oven also has less warmed-over flavor. An obvious nutritional benefit of cooking is the fact that heat lowers the fat content of beef by liquif ying the fat so it can run off the meat. One concrete example of how well this works comes from a comparison of the fat content in regular and extra-lean ground beef. According to research at the University of Missouri in 1985, both kinds of beef lose mass when cooked, but the lean beef loses water and the regular beef loses fat and cholesterol. Thus, while regular raw ground beef has about three times as much fat (by weight) as raw ground extra-lean beef, their fat varies by only 5 percent after broiling. To reduce the amount of fat in ground beef, heat the beef in a pan until it browns. Then put the beef in a colander, and pour one cup of warm water over the beef. Repeat with a second cup of warm water to rinse away fat melted by heating the beef. Use the ground beef in sauce and other dishes that do not require it to hold together. Finally, cooking makes beef safer by killing Salmonella and other organisms in the meat. As a result, cooking also serves as a natural preservative. According to the USDA, large pieces of fresh beef can be refrigerated for two or three days, then cooked and held safely for another day or two because the heat of cooking has reduced the number of bacteria on the surface of the meat and temporarily interrupted the natural cycle of deterioration.
How Other Kinds of Processing Affect This Food Aging. Hanging fresh meat exposed to the air, in a refrigerated room, reduces the moisture content and shrinks the meat slightly. As the meat ages enzymes break down muscle pro- teins, “tenderizing” the beef. Canning. Canned beef does not develop a warmed-over flavor because the high tempera- tures in canning food and the long cooking process alter proteins in the meat so that they act as antioxidants. Once the can is open, however, the meat should be protected from oxygen that will change the flavor of the beef. Curing. Salt-curing preserves meat through osmosis, the physical reaction in which liquids flow across a membrane, such as the wall of a cell, from a less dense to a more dense solution. The salt or sugar used in curing dissolves in the liquid on the surface of the meat to make a solution that is more dense than the liquid inside the cells of the meat. Water flows out of the meat and out of the cells of any microorganisms living on the meat, killing the microor- ganisms and protecting the meat from bacterial damage. Salt-cured meat is much higher in sodium than fresh meat. Freezing. When you freeze beef, the water inside its cells freezes into sharp ice crystals that can puncture cell membranes. When the beef thaws, moisture (and some of the B vitamins) will leak out through these torn cell walls. The loss of moisture is irreversible, but some of the vitamins can be saved by using the drippings when the meat is cooked. Freezing may also cause freezer burn—dry spots left when moisture evaporates from the surface of the meat. Waxed freezer paper is designed specifically to hold the moisture in meat; plastic wrap and aluminum foil are less effective. NOTE : Commercially prepared beef, which is frozen very quickly at very low temperatures, is less likely to show changes in texture. Irradiation. Irradiation makes meat safer by exposing it to gamma rays, the kind of high- energy ionizing radiation that kills living cells, including bacteria. Irradiation does not change the way meat looks, feels or tastes, or make the food radioactive, but it does alter the structure of some naturally occurring chemicals in beef, breaking molecules apart to form new com- pounds called radiolytic products (R P). About 90 percent of R Ps are also found in nonirradiated foods. The rest, called unique radiolytic products (UR P), are found only in irradiated foods. There is currently no evidence to suggest that UR Ps are harmful; irradiation is an approved technique in more than 37 countries around the world, including the United States. Smoking. Hanging cured or salted meat over an open fire slowly dries the meat, kills micro- organisms on its surface, and gives the meat a rich, “smoky” flavor that varies with the wood used in the fire. Meats smoked over an open fire are exposed to carcinogenic chemicals in the smoke, including a-benzopyrene. Meats treated with “artificial smoke flavoring” are not, since the flavoring is commercially treated to remove tar and a-benzopyrene.
Medical Uses and/or Benefits Treating and/or preventing iron deficiency. Without meat in the diet, it is virtually impossible for an adult woman to meet her iron requirement without supplements. One cooked 3.5- ounce hamburger provides about 2.9 mg iron, 16 percent of the R DA for an adult woman of childbearing age. Possible anti-diabetes activity. CLA may also prevent type 2 diabetes, also called adult-onset diabetes, a non-insulin-dependent form of the disease. At Purdue University, rats bred to develop diabetes spontaneously between eight and 10 weeks of age stayed healthy when given CLA supplements.
Adverse Effects Associated with This Food Increased risk of heart disease. Like other foods from animals, beef contains cholesterol and saturated fats that increase the amount of cholesterol circulating in your blood, raising your risk of heart disease. To reduce the risk of heart disease, the National Cholesterol Education Project recommends following the Step I and Step II diets. The Step I diet provides no more than 30 percent of total daily calories from fat, no more than 10 percent of total daily calories from saturated fat, and no more than 300 mg of cholesterol per day. It is designed for healthy people whose cholesterol is in the range of 200 –239 mg/dL. The Step II diet provides 25– 35 percent of total calories from fat, less than 7 percent of total calories from saturated fat, up to 10 percent of total calories from polyunsaturated fat, up to 20 percent of total calories from monounsaturated fat, and less than 300 mg cho- lesterol per day. This stricter regimen is designed for people who have one or more of the following conditions: • Existing cardiovascular disease • High levels of low-density lipoproteins (LDLs, or “bad” cholesterol) or low levels of high-density lipoproteins (HDLs, or “good” cholesterol) • Obesity • Type 1 diabetes (insulin-dependent diabetes, or diabetes mellitus) • Metabolic syndrome, a.k.a. insulin resistance syndrome, a cluster of risk fac- tors that includes type 2 diabetes (non-insulin-dependent diabetes) Increased risk of some cancers. According the American Institute for Cancer Research, a diet high in red meat (beef, lamb, pork) increases the risk of developing colorectal cancer by 15 percent for every 1.5 ounces over 18 ounces consumed per week. In 2007, the National Can- cer Institute released data from a survey of 500,000 people, ages 50 to 71, who participated in an eight-year A AR P diet and health study identif ying a higher risk of developing cancer of the esophagus, liver, lung, and pancreas among people eating large amounts of red meats and processed meats. Food-borne illness. Improperly cooked meat contaminated with E. coli O157:H7 has been linked to a number of fatalities in several parts of the United States. In addition, meats con- taminated with other bacteria, viruses, or parasites pose special problems for people with a weakened immune system: the very young, the very old, cancer chemotherapy patients, and people with HIV. Cooking meat to an internal temperature of 140°F should destroy Salmo- nella and Campylobacter jejuni; 165°F, the E. coli organism; and 212°F, Listeria monocytogenes. Antibiotic sensitivity. Cattle in the United States are routinely given antibiotics to protect them from infection. By law, the antibiotic treatment must stop three days to several weeks before the animal is slaughtered. Theoretically, the beef should then be free of antibiotic residues, but some people who are sensitive to penicillin or tetracycline may have an allergic reaction to the meat, although this is rare. Antibiotic-resistant Salmonella and toxoplasmosis. Cattle treated with antibiotics may pro- duce meat contaminated with antibiotic-resistant strains of Salmonella, and all raw beef may harbor ordinary Salmonella as well as T. gondii, the parasite that causes toxoplasmosis. Toxoplasmosis is particularly hazardous for pregnant women. It can be passed on to the fetus and may trigger a series of birth defects including blindness and mental retardation. Both Salmonella and the T. gondii can be eliminated by cooking meat thoroughly and washing all utensils, cutting boards, and counters as well as your hands with hot soapy water before touching any other food. Decline in kidney function. Proteins are nitrogen compounds. When metabolized, they yield ammonia, which is excreted through the kidneys. In laborator y animals, a sustained high-protein diet increases the flow of blood through the kidneys, accelerating the natural age-related decline in kidney function. Some experts suggest that this may also occur in human beings.
Food/Drug Interactions Tetracycline antibiotics (demeclocycline [Declomycin], doxycycline [ Vibtamycin], methacycline [Rondomycin], minocycline [Minocin], oxytetracycline [Terramycin], tetracycline [Achromycin V, Panmycin, Sumycin]). Because meat contains iron, which binds tetracyclines into com- pounds the body cannot absorb, it is best to avoid meat for two hours before and after taking one of these antibiotics. Monoamine oxidase (MAO) inhibitors. Meat “tenderized” with papaya or a papain powder can interact with the class of antidepressant drugs known as monoamine oxidase inhibi- tors. Papain meat tenderizers work by breaking up the long chains of protein molecules. One by-product of this process is tyramine, a substance that constructs blood vessels and raises blood pressure. M AO inhibitors inactivate naturally occurring enzymes in your body that metabolize tyramine. If you eat a food such as papain-tenderized meat, which is high in tyramine, while you are taking a M AO inhibitor, you cannot effectively eliminate the tyramine from your body. The result may be a hypertensive crisis. Theophylline. Charcoal-broiled beef appears to reduce the effectiveness of theophylline because the aromatic chemicals produced by burning fat speed up the metabolism of the- ophylline in the liver.... beef
Nutritional Profile Energy value (calories per serving): High Protein: Low Fat: High Saturated fat: High Cholesterol: High Carbohydrates: Low Fiber: None Sodium: Low (unsalted butter) High (salted butter) Major vitamin contribution: Vitamin A, vitamin D Major mineral contribution: None
About the Nutrients in This Food Butterfat is 62 percent saturated fatty acids, 35 percent monounsaturated fatty acids, and 4 percent polyunsaturated fatty acids. One tablespoon of butter has 11 g of fat, 7.1 g of saturated fat, and 31 mg cholesterol, and 1,070 IU vitamin A (46 percent of the R DA for a woman, 36 percent of the R DA for a man). The vitamin A is derived from carotenoids in plants eaten by the milk-cow.
Diets That May Restrict or Exclude This Food Low-cholesterol, controlled-fat diet Sodium-restricted diet (salted butter)
Buying This Food Look for: Fresh butter. Check the date on the package.
Storing This Food Store butter in the refrigerator, tightly wrapped to protect it from air and prevent it from picking up the odors of other food. Even refrigerated butter will eventually turn rancid as its fat molecules combine with oxygen to produce hydroperoxides that, in turn, break down into chemicals with an unpleasant flavor and aroma. This reaction is slowed (but not stopped) by cold. Because salt retards the combination of fats with oxygen, salted butter stays fresh longer than plain butter. (Lard, which is pork fat, must also be refrigerated. Lard has a higher proportion of unsaturated fats than the butter. Since unsaturated fats combine with oxygen more easily than saturated fats, lard becomes rancid more quickly than butter.)
Preparing This Food To measure a half-cup of butter. Pour four ounces of water into an eight-ounce measuring cup, then add butter until the water rises to the eight-ounce mark. Scoop out the butter, use as directed in recipe.
What Happens When You Cook This Food Fats are very useful in cooking. They keep foods from sticking to the pot or pan; add fla- vor; and, as they warm, transfer heat from the pan to the food. In doughs and batters, fats separate the flour’s starch granules from each other. The more closely the fat mixes with the starch, the smoother the bread or cake will be. Heat speeds the oxidation and decomposition of fats. When fats are heated, they can catch fire spontaneously without boiling first at what is called the smoke point. Butter will burn at 250°F.
How Other Kinds of Processing Affect This Food Freezing. Freezing slows the oxidation of fats more effectively than plain refrigeration; frozen butter keeps for up to nine months. Whipping. When butter is whipped, air is forced in among the fat molecules to produce a foam. As a result, the whipped butter has fewer calories per serving, though not per ounce.
Adverse Effects Associated with This Food Increased risk of heart disease. Like other foods from animals, butter contains cholesterol and saturated fats. Eating butter increases the amount of cholesterol circulating in your blood and raise your risk of heart disease. To reduce the risk of heart disease, USDA /Health and Human Services Dietary Guidelines for Americans recommends limiting the amount of cholesterol in your diet to no more than 300 mg a day. The guidelines also recommend limit- ing the amount of fat you consume to no more than 30 percent of your total calories, while holding your consumption of saturated fats to no more than 10 percent of your total calories (the calories from saturated fats are counted as part of the total calories from fat). Increased risk of acid reflux. Consuming excessive amounts of fats and fatty foods loosens the lower esophageal sphincter (LES), a muscular valve between the esophagus and the stomach. When food is swallowed, the valve opens to let food into the stomach, then closes tightly to keep acidic stomach contents from refluxing (flowing backwards) into the esopha- gus. If the LES does not close efficiently, the stomach contents reflux to cause heartburn, a burning sensation. Repeated reflux is a risk factor for esophageal cancer.... butter
Nutritional Profile Energy value (calories per serving): Moderate Protein: High Fat: Low to moderate Saturated fat: Low to moderate Cholesterol: Moderate Carbohydrates: Low Fiber: None Sodium: Low (fresh fish) High (some canned or salted fish) Major vitamin contribution: Vitamin A, vitamin D Major mineral contribution: Iodine, selenium, phosphorus, potassium, iron, calcium
About the Nutrients in This Food Like meat, poultry, milk, and eggs, fish are an excellent source of high- quality proteins with sufficient amount of all the essential amino acids. While some fish have as much or more fat per serving than some meats, the fat content of fish is always lower in saturated fat and higher in unsaturated fats. For example, 100 g/3.5 ounce cooked pink salmon (a fatty fish) has 4.4 g total fat, but only 0.7 g saturated fat, 1.2 g monounsaturated fat, and 1.7 g polyunsaturated fat; 100 g/3.5 ounce lean top sirloin has four grams fat but twice as much saturated fat (1.5 g), plus 1.6 g monounsatu- rated fat and only 0.2 g polyunsaturated fat. Omega-3 Fatty Acid Content of Various Fish (Continued) Fish Grams/ounce Rainbow trout 0.30 Lake whitefish 0.25 Source: “Food for t he Heart,” American Health, April 1985. Fish oils are one of the few natural food sources of vitamin D. Salmon also has vita- min A derived from carotenoid pigments in the plants eaten by the fish. The soft bones in some canned salmon and sardines are an excellent source of calcium. CAUTION: do not eat the bones in r aw or cook ed fish. the only bones consider ed edible ar e those in the canned products.
The Most Nutritious Way to Serve This Food Cooked, to kill parasites and potentially pathological microorganisms living in raw fish. Broiled, to liquify fat and eliminate the fat-soluble environmental contaminants found in some freshwater fish. With the soft, mashed, calcium-rich bones (in canned salmon and canned sardines).
Diets That May Restrict or Exclude This Food Low-purine (antigout) diet Low-sodium diet (canned, salted, or smoked fish)
Buying This Food Look for: Fresh-smelling whole fish with shiny skin; reddish pink, moist gills; and clear, bulging eyes. The flesh should spring back when you press it lightly. Choose fish fillets that look moist, not dry. Choose tightly sealed, solidly frozen packages of frozen fish. In 1998, the FDA /National Center for Toxicological Research released for testing an inexpensive indicator called “Fresh Tag.” The indicator, to be packed with seafood, changes color if the product spoils. Avoid: Fresh whole fish whose eyes have sunk into the head (a clear sign of aging); fillets that look dry; and packages of frozen fish that are stained (whatever leaked on the package may have seeped through onto the fish) or are coated with ice crystals (the package may have defrosted and been refrozen).
Storing This Food Remove fish from plastic wrap as soon as you get it home. Plastic keeps out air, encouraging the growth of bacteria that make the fish smell bad. If the fish smells bad when you open the package, throw it out. Refrigerate all fresh and smoked fish immediately. Fish spoils quickly because it has a high proportion of polyunsaturated fatty acids (which pick up oxygen much more easily than saturated or monounsaturated fatty acids). Refrigeration also slows the action of microorgan- isms on the surface of the fish that convert proteins and other substances to mucopolysac- charides, leaving a slimy film on the fish. Keep fish frozen until you are ready to use it. Store canned fish in a cool cabinet or in a refrigerator (but not the freezer). The cooler the temperature, the longer the shelf life.
Preparing This Food Fresh fish. Rub the fish with lemon juice, then rinse it under cold running water. The lemon juice (an acid) will convert the nitrogen compounds that make fish smell “fishy” to compounds that break apart easily and can be rinsed off the fish with cool running water. R insing your hands in lemon juice and water will get rid of the fishy smell after you have been preparing fresh fish. Frozen fish. Defrost plain frozen fish in the refrigerator or under cold running water. Pre- pared frozen fish dishes should not be thawed before you cook them since defrosting will make the sauce or coating soggy. Salted dried fish. Salted dried fish should be soaked to remove the salt. How long you have to soak the fish depends on how much salt was added in processing. A reasonable average for salt cod, mackerel, haddock (finnan haddie), or herring is three to six hours, with two or three changes of water. When you are done, clean all utensils thoroughly with hot soap and hot water. Wash your cutting board, wood or plastic, with hot water, soap, and a bleach-and-water solution. For ultimate safety in preventing the transfer of microorganisms from the raw fish to other foods, keep one cutting board exclusively for raw fish, meats, and poultry, and a second one for everything else. Finally, don’t forget to wash your hands.
What Happens When You Cook This Food Heat changes the structure of proteins. It denatures the protein molecules so that they break apart into smaller fragments or change shape or clump together. These changes force moisture out of the tissues so that the fish turns opaque. The longer you cook fish, the more moisture it will lose. Cooked fish flakes because the connective tissue in fish “melts” at a relatively low temperature. Heating fish thoroughly destroys parasites and microorganisms that live in raw fish, making the fish safer to eat.
How Other Kinds of Processing Affect This Food Marinating. Like heat, acids coagulate the proteins in fish, squeezing out moisture. Fish marinated in citrus juices and other acids such as vinegar or wine has a firm texture and looks cooked, but the acid bath may not inactivate parasites in the fish. Canning. Fish is naturally low in sodium, but can ned fish often contains enough added salt to make it a high-sodium food. A 3.5-ounce ser ving of baked, fresh red salmon, for example, has 55 mg sodium, while an equal ser ving of regular can ned salmon has 443 mg. If the fish is can ned in oil it is also much higher in calories than fresh fish. Freezing. When fish is frozen, ice cr ystals form in the flesh and tear its cells so that mois- ture leaks out when the fish is defrosted. Commercial flash-freezing offers some protec- tion by freezing the fish so fast that the ice cr ystals stay small and do less damage, but all defrosted fish tastes drier and less palatable than fresh fish. Freezing slows but does not stop the oxidation of fats that causes fish to deteriorate. Curing. Fish can be cured (preser ved) by smoking, dr ying, salting, or pickling, all of which coagulate the muscle tissue and prevent microorganisms from growing. Each method has its own particular drawbacks. Smoking adds potentially carcinogenic chemicals. Dr ying reduces the water content, concentrates the solids and nutrients, increases the calories per ounce, and raises the amount of sodium.
Medical Uses and/or Benefits Protection against cardiovascular disease. The most important fats in fish are the poly- unsaturated acids k nown as omega-3s. These fatt y acids appear to work their way into heart cells where they seem to help stabilize the heart muscle and prevent potentially fatal arrhythmia (irregular heartbeat). A mong 85,000 women in the long-run n ing Nurses’ Health Study, those who ate fatt y fish at least five times a week were nearly 50 percent less likely to die from heart disease than those who ate fish less frequently. Similar results appeared in men in the equally long-run n ing Physicians’ Health Study. Some studies suggest that people may get similar benefits from omega-3 capsules. Researchers at the Consorzio Mario Negri Sud in Santa Maria Imbaro ( Italy) say that men given a one-gram fish oil capsule once a day have a risk of sudden death 42 percent lower than men given placebos ( “look-alike” pills with no fish oil). However, most nutrition scientists recom- mend food over supplements. Omega-3 Content of Various Food Fish Fish* (3 oz.) Omega-3 (grams) Salmon, Atlantic 1.8 Anchovy, canned* 1.7 Mackerel, Pacific 1.6 Salmon, pink, canned* 1.4 Sardine, Pacific, canned* 1.4 Trout, rainbow 1.0 Tuna, white, canned* 0.7 Mussels 0.7 * cooked, wit hout sauce * drained Source: Nat ional Fisheries Inst itute; USDA Nut rient Data Laborator y. Nat ional Nut ri- ent Database for Standard Reference. Available online. UR L : http://w w w.nal.usda. gov/fnic/foodcomp/search /.
Adverse Effects Associated with This Food Allergic reaction. According to the Merck Manual, fish is one of the 12 foods most likely to trigger classic food allergy symptoms: hives, swelling of the lips and eyes, and upset stom- ach. The others are berries (blackberries, blueberries, raspberries, strawberries), chocolate, corn, eggs, legumes (green peas, lima beans, peanuts, soybeans), milk, nuts, peaches, pork, shellfish, and wheat (see wheat cer ea ls). NOTE : Canned tuna products may contain sulfites in vegetable proteins used to enhance the tuna’s flavor. People sensitive to sulfites may suf- fer serious allergic reactions, including potentially fatal anaphylactic shock, if they eat tuna containing sulfites. In 1997, tuna manufacturers agreed to put warning labels on products with sulfites. Environmental contaminants. Some fish are contaminated with methylmercury, a compound produced by bacteria that chemically alters naturally occurring mercury (a metal found in rock and soil) or mercury released into water through industrial pollution. The methylmer- cury is absorbed by small fish, which are eaten by larger fish, which are then eaten by human beings. The larger the fish and the longer it lives the more methylmercury it absorbs. The measurement used to describe the amount of methylmercury in fish is ppm (parts per mil- lion). Newly-popular tilapia, a small fish, has an average 0.01 ppm, while shark, a big fish, may have up to 4.54 ppm, 450 times as much. That is a relatively small amount of methylmercur y; it will soon make its way harmlessly out of the body. But even small amounts may be hazardous during pregnancy because methylmercur y targets the developing fetal ner vous system. Repeated studies have shown that women who eat lots of high-mercur y fish while pregnant are more likely to deliver babies with developmental problems. As a result, the FDA and the Environ men- tal Protection Agency have now warned that women who may become pregnant, who are pregnant, or who are nursing should avoid shark, swordfish, king mackerel, and tilefish, the fish most likely to contain large amounts of methylmercur y. The same prohibition applies to ver y young children; although there are no studies of newborns and babies, the young brain continues to develop after birth and the logic is that the prohibition during pregnancy should extend into early life. That does not mean no fish at all should be eaten during pregnancy. In fact, a 2003 report in the Journal of Epidemiology and Community Health of data from an 11,585-woman study at the University of Bristol (England) shows that women who don’t eat any fish while pregnant are nearly 40 percent more likely to deliver low birth-weight infants than are women who eat about an ounce of fish a day, the equivalent of 1/3 of a small can of tuna. One theory is that omega-3 fatty acids in the fish may increase the flow of nutrient-rich blood through the placenta to the fetus. University of Southern California researchers say that omega-3s may also protect some children from asthma. Their study found that children born to asthmatic mothers who ate oily fish such as salmon at least once a month while pregnant were less likely to develop asthma before age five than children whose asthmatic pregnant mothers never ate oily fish. The following table lists the estimated levels of mercury in common food fish. For the complete list of mercury levels in fish, click onto www.cfsan.fda.gov/~frf/sea-mehg.html. Mercury Levels in Common Food Fish Low levels (0.01– 0.12 ppm* average) Anchovies, butterfish, catfish, clams, cod, crab (blue, king, snow), crawfish, croaker (Atlantic), flounder, haddock, hake, herring, lobster (spiny/Atlantic) mackerel, mul- let, ocean perch, oysters, pollock, salmon (canned/fresh frozen), sardines, scallops, shad (American), shrimp, sole, squid, tilapia, trout (freshwater), tuna (canned, light), whitefish, whiting Mid levels (0.14 – 0.54 ppm* average) Bass (salt water), bluefish, carp, croaker ( Pacific), freshwater perch, grouper, halibut, lobster (Northern A merican), mackerel (Spanish), marlin, monkfish, orange roughy, skate, snapper, tilefish (Atlantic), tuna (can ned albacore, fresh/frozen), weakfish/ sea trout High levels (0.73 –1.45 ppm* average) King mackerel, shark, swordfish, tilefish * ppm = parts per million, i.e. parts of mercur y to 1,000,000 parts fish Source: U.S. Food and Drug Administ rat ion, Center for Food Safet y and Applied Nut rit ion, “Mercur y Levels in Commercial Fish and Shellfish.” Available online. UR L : w w w.cfsan.fda. gov/~frf/sea-mehg.ht ml. Parasitical, viral, and bacterial infections. Like raw meat, raw fish may carry various pathogens, including fish tapeworm and flukes in freshwater fish and Salmonella or other microorganisms left on the fish by infected foodhandlers. Cooking the fish destroys these organisms. Scombroid poisoning. Bacterial decomposition that occurs after fish is caught produces a his- taminelike toxin in the flesh of mackerel, tuna, bonito, and albacore. This toxin may trigger a number of symptoms, including a flushed face immediately after you eat it. The other signs of scombroid poisoning—nausea, vomiting, stomach pain, and hives—show up a few minutes later. The symptoms usually last 24 hours or less.
Food/Drug Interactions Monoamine oxidase (MAO) inhibitors. Monoamine oxidase inhibitors are drugs used to treat depression. They inactivate naturally occurring enzymes in your body that metabolize tyramine, a substance found in many fermented or aged foods. Tyramine constricts blood vessels and increases blood pressure. If you eat a food such as pickled herring, which is high in tyramine, while you are taking an M AO inhibitor, your body may not be able to eliminate the tyramine and the result may be a hypertensive crisis.... fish