Nutrition Glossary (cont.)
Calcium deficiency: A low blood calcium
(hypocalcemia). Hypocalcemia makes the nervous system highly
irritable with tetany (spasms
of the hands and feet, muscle cramps, abdominal cramps, overly active
reflexes, etc.).
Chronic calcium deficiency contributes to poor mineralization of
bones, soft bones
(osteomalacia) and osteoporosis; and, in children, rickets and
impaired growth. Food
sources of calcium include dairy foods, some leafy green vegetables
such as broccoli and
collards, canned salmon, clams, oysters, calcium-fortified foods, and
tofu. According to
the National Academy of Sciences, adequate intake of calcium is 1
gram daily for both men
and women. The upper limit for calcium intake is 2.5 grams
daily.
Calorie: A unit of food energy. In
nutrition
terms, the
word calorie is used instead of the more precise scientific
term
kilocalorie. A kilocalorie represents the amount of energy
required
to raise the temperature of a liter of water one
degree centigrade at sea level. Technically, however, this
common
usage of the word calorie of food energy is understood to
refer to a
kilocalorie (and actually represents, therefore, 1000 true
calories
of energy).
Carbohydrate: One of the three
nutrients that are used as energy sources (calories) by the
body. (The other energy sources are in the form of fats
and proteins. Carbohydrates come in the form of simple
sugars and complex forms, such as starches and fiber.
Complex carbohydrates come naturally from plants. Intake
of complex carbohydrates can lower blood cholesterol when
they are substituted for saturated fat. The energy
produced by carbohydrates is 4 calories per gram. Proteins
also provide 4 calories per gram, while fats provide 9
calories per gram.
Carbohydrate loading: Carbohydrate
loading is a technique
used
to increase the amount of glycogen in muscles. For five to seven
days before an event, the athlete eats 10-12 grams of carbohydrate
per kilogram of body weight, while gradually reducing the intensity
of workouts. (To find out how much you weigh in kilograms, simply
divide your weight in pounds by 2.2.)The day before the event, the
athlete rests and eats the same high- carbohydrate diet. Most
athletes should not worry about carbohydrate loading. If they eat a
diet that derives more than half of its calories from carbohydrates,
their body will have adequate levels to fuel their athletic activity.
Carbohydrate loading may be beneficial for athletes engaged in
endurance sports which require 90 minutes or more of non-stop effort.
Celiac Disease:A disorder resulting from an
immune
reaction to
gluten,
a protein
found in wheat and related grains, and present in many foods. Celiac disease
causes impaired
absorption
and digestion of nutrients through the
small
intestine. Symptoms include frequent
diarrhea
and weight loss. A skin condition dermatitis herpetiformis can be associated
with celiac disease. The most accurate test for celiac disease is a
biopsy
of the involved
small
bowel. Treatment is to avoid gluten in the diet. Medications are used for
refractory
(stubborn) celiac disease.
Cholesterol: The most common type of
steroid in the
body, cholesterol has gotten something of a bad name.
However,
cholesterol is a critically important molecule. It is
essential to
the formation of:
- Bile acids (which aid in the digestion of fats)
- Vitamin D
- Progesterone
- Estrogens (estradiol, estrone, estriol)
- Androgens (androsterone, testosterone)
- Mineralocorticoid hormones (aldosterone,
corticosterone) and
- Glucocorticoid hormones (cortisol).
Cholesterol is also necessary to the normal permeability
and function of cell membranes, the membranes that surround
cells.
Cholesterol is carried in the bloodstream as
lipoproteins.
Low-density lipoprotein (LDL) cholesterol is the
"bad" cholesterol because elevated LDL levels are
associated with an increased risk of coronary artery
(heart) disease. Conversely, high-density lipoprotein (HDL)
cholesterol is the "good" cholesterol since
high HDL levels are associated with less coronary
disease.
After the age of 20, cholesterol testing is recommended
every 5
years.
A diet high in saturated fats tends to increase
the blood cholesterol levels while diets high in
unsaturated fats tend to do the opposite, to lower blood
cholesterol
levels.
Although some cholesterol is obtained from the diet,
most
cholesterol is made in the liver and other
tissues. The treatment of elevated cholesterol therefore
involves not
only diet but also weight loss and regular exercise
(and, occasionally, medications).
Chondroitin Sulfate: A glycosaminoglycan
(formerly called a mucopolysaccharide) found in cartilage, bone, blood vessels
and connective tissues. There are two forms: chondroitin sulfate A and
chondroitin sulfate C. One or both types accumulate abnormally in several of the
mucopolysaccharidosis disorders. Chondroitin sulfate B is now called dermatan
sulfate.
DASH Diet: An eating plan designed to lower the blood pressure. DASH is an acronym for Dietary Approaches to Stop Hypertension. The DASH "combination
diet" has been shown to decrease the blood pressure and so helps prevent and control
high blood pressure. The DASH "combination diet" is rich in fruits, vegetables, and low fat dairy foods, and low in saturated and total
fat. It also is low in
cholesterol, high in dietary
fiber,
potassium, calcium, and magnesium, and moderately high in protein.