Encyclopedia of Health and Medicine

NUTRITION AND DIET
The science of nutrition concerns itself with the ways in which foods influence health and disease. A health-care practitioner
who specializes in nutrition may be a registered dietitian (RD), registered nurse (RN), physician (MD or DO),
naturopathic physician (ND), pharmacist (RPh or PharmD), or chiropractor (DC). The general term nutritionist is in
common use to identify a health-care professional who specializes in matters of nutrition but does not consistently designate
specific education, training, qualifications, or credentials.
This section, “Nutrition and Diet,” presents an
overview discussion of nutritional concepts as
they relate to health, health risk factors, and preventive
health measures. The entries in this section
focus on the broad picture of how nutrition
and diet influence health and disease. The section,
“Lifestyle: Obesity and Smoking,” provides discussion
and content of nutritional topics that relate
to WEIGHT LOSS AND WEIGHT MANAGEMENT.
Making the Connection between Diet and Health
Though the mechanisms of nutrition remained
unknown until the early 20th century, doctors
were quite familiar with the diseases of nutritional
deficiencies. Ancient Egyptian physicians
identified the disease now called SCURVY, which for
centuries was the bane of sailors who spent
months to years at sea on ships with no fruits or
vegetables to supply needed vitamins and minerals.
Biscuits and salt pork sustained life but they
did not support nutrition. Not until the middle of
the 18th century did ships’ surgeons recognize
that citrus fruits (namely lemons, limes, and
oranges) could cure as well as prevent scurvy
among sailors.
BERIBERI
NIGHT BLINDNESS
PELLAGRA
RICKETS
HEALTH CONDITIONS RESULTING
FROM NUTRITIONAL DEFICIENCIES
MALNUTRITION
OSTEOPOROSIS
pernicious ANEMIA
SCURVY
Among the most famous names in medical
nutrition is John Harvey Kellogg (1852–1943), a
late-19th-century American physician and surgeon
whose belief that diet was the foundation of
good health launched what would become one of
the world’s largest and most successful cereal
companies. Kellogg came up with a recipe for a
simple, nutritious breakfast food to serve at the
sanitarium where he was at the time the director:
cornflakes. The product based on the recipe
became itself an American institution. Kellogg
implemented many practices based on nutrition
during his tenure at the sanitarium, gaining
prominence for them in a time when other medical
alternatives were fairly nonexistent.
In the flood of transforming discoveries sweeping
the practice of medicine, diet was not especially
exciting and its connections to health
unproven. Researchers discovered aspirin, INSULIN,
antibiotics, immunizations, and ANESTHESIA. Surgeons
invaded the belly, chest, and cranium. Kellogg,
himself a talented surgeon, developed a
number of surgical techniques and the instruments
to carry them out. Though Kellogg’s cornflakes
became a national phenomenon, doctors
did not pay much attention to the role of diet—
the kinds and amounts of foods people eat—in
health unless they were treating conditions resulting
from or that caused NUTRITIONAL DEFICIENCY or
toxicity.
About the time John F. Kennedy became US
president, researchers established the first diet–
disease correlation, that between cholesterol and
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