included two ounces (55 g) of foods containing lactic acid (milk, cheese, and yogurt) were
significantly less likely to have deep “pockets” (loss of attachment of tooth to gum) than
those who consumed fewer dairy products.
Adverse Effects Associated with This Food
Increased risk of heart disease. Like other foods from animals, cheese is a source of choles-
terol and saturated fats, which increase the amount of cholesterol circulating in your blood
and raise your risk of heart disease. To reduce the risk of heart disease, the 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 more than 10 percent of your total calories (the
calories from saturated fats are counted as part of the total calories from fat).
Food poisoning. Cheese made from raw (unpasteurized) milk may contain hazardous
microorganisms, including Salmonella and Listeria. Salmonella causes serious gastric upset; Lis-
teria, a flulike infection, encephalitis, or blood infection. Both may be life-threatening to the
very young, the very old, pregnant women, and those whose immune systems are weakened
either by illness (such as AIDS) or drugs (such as cancer chemotherapy). In 1998, the Federal
Centers for Disease Control (CDC) released data identifying Listeria as the cause of nearly
half the reported deaths from food poisoning.
Allergy to milk proteins. Milk is one of the foods most frequently implicated as a cause of
allergic reactions, particularly upset stomach. However, in many cases the reaction is not a
true allergy but the result of lactose intolerance (see below).
Lactose intolerance. Lactose intolerance—the inability to digest the sugar in milk—is an
inherited metabolic deficiency that affects two thirds of all adults, including 90 to 95 percent
of all Orientals, 70 to 75 percent of all blacks, and 6 to 8 percent of Caucasians. These people
do not have sufficient amounts of lactase, the enzyme that breaks the disaccharide lactose
into its easily digested components, galactose and glucose. When they drink milk, the undi-
gested sugar is fermented by bacteria in the gut, causing bloating, diarrhea, flatulence, and
intestinal discomfort. Some milk is now sold with added lactase to digest the lactose and
make the milk usable for lactase-deficient people. In making cheese, most of the lactose in
milk is broken down into glucose and galactose. There is very little lactose in cheeses other
than the fresh ones—cottage cheese, cream cheese, and farmer cheese.
Galactosemia. Galactosemia is an inherited metabolic disorder in which the body lacks the
enzymes needed to metabolize galactose, a component of lactose. Galactosemia is a reces-
sive trait; you must receive the gene from both parents to develop the condition. Babies born
with galactosemia will fail to thrive and may develop brain damage or cataracts if they are
given milk. To prevent this, children with galactosemia are usually kept on a protective milk-
free diet for several years, until their bodies have developed alternative pathways by which
Cheese