Gilden Tsai, A., and T. A. Wadden. ‘‘The Evolution of
Very-Low-Calorie Diets: An Update and Meta-Analysis.’’
Obesity(Silver Spring) 14 (August 2006): 1283–1293.
Hart, K. E., and E. M. Warriner. ‘‘Weight Loss and
Biomedical Health Improvement on a Very Low
Calorie Diet: The Moderating Role of History of
Weight Cycling.’’Behavioral Medicine30 (Winter
2005): 161–170.
Maxted, Anna. ‘‘Slimmer after 16 Years of Diets? Huh, Fat
Chance.’’The Independent(London), July 16, 1995.
National Task Force on the Prevention and Treatment of
Obesity, National Institutes of Health. ‘‘Very Low-
Calorie Diets.’’Journal of the American Medical Asso-
ciation270 (August 25, 1993): 967–974.
Quiroz-Kendall, E., F. A. Wilson, and L. E. King, Jr. ‘‘Acute
Variegate Porphyria Following a Scarsdale Gourmet
Diet.’’Journal of the American Academy of Dermatol-
ogy8 (January 1983): 46-49.
Saris, W. H. ‘‘Very-Low-Calorie Diets and Sustained Weight
Loss.’’Obesity Research9 (Suppl. 4): 295S–301S.
‘‘Top 25 Best-Selling Hardcovers of 1979.’’ Time Capsule,
Home Textiles Today, September 6, 2004, 36.
Weber, Melva. ‘‘The Scarsdale-diet Rage.’’Vogue169 (Jan-
uary 1979): 139-140.
Wing, R. R., L. H. Epstein, and B. Shapira. ‘‘The Effect of
Increasing Initial Weight Loss with the Scarsdale Diet on
Subsequent Weight Loss in a Behavioral Treatment
Program.’’Journal of Consulting and Clinical Psychology
50 (June 1982): 446-447.
OTHER
American Dietetic Association (ADA).Fad Diet Timeline—
Fad Diets throughout the Years. Press release, February
1, 2007. Available online at http://www.eatright.org/cps/
rde/xchg/ada/hs.xsl/media_11092_ENU_HTML.htm.
ORGANIZATIONS
American Academy of Family Physicians (AAFP). P.O. Box
11210, Shawnee Mission, KS 66207-1210. Telephone:
(800) 274-2237 or (913) 906-6000. Website: http://
http://www.aafp.org.
American Dietetic Association (ADA). 120 South Riverside
Plaza, Suite 2000, Chicago, IL 60606-6995. Telephone:
(800): 877-1600. Website: http://www.eatright.org.
Dietitians of Canada/Les die ́te ́tistes du Canada (DC). 480
University Avenue, Suite 604, Toronto, Ontario, Can-
ada M5G 1V2. Telephone: (416) 596-0857. Website:
http://www.dietitians.ca.
Partnership for Healthy Weight Management (PHWM), c/o
Federal Trade Commission (FTC), Bureau of Consumer
Protection. 601 Pennsylvania Avenue, NW, Room 4302,
Washington, DC. 20580. Website: http://www.consumer.
gov/weightloss/.Rebecca J Frey, PhDScottish dietseeNorthern European diet
ScurvyseeVitamin C
Selenium
DefinitionSelenium is a trace element considered a micro-
nutrient, meaning a nutrient needed in very small
amounts, that is required as an essential cofactor for
the antioxidant enzymes of the body to counteract the
damaging effects of reactive oxygen in tissues.Purpose
The body requires selenium for the function of a
special class of enzymes, called selenoproteins. Proteins
are long folded chains of amino acids and selenoproteins
are made by the body (selenoprotein synthesis), by
incorporating dietary selenium in the form of an
unusual amino acid, called selenocysteine, into a very
specific location in their amino acid sequence. Animals
and humans both require selenium, but not plants.
Plants can however, incorporate selenium present in
the soil into compounds that usually also contain sulfur.
The major function of selenoproteins is to prevent
or reduce the damage (oxidative stress) caused by
reactive oxygen species (ROS) or reactive nitrogen
species (RNS). These can occur in the body mostly in
the form of free radicals, such as peroxides. There are
many types of selenoprotein enzymes that protect cells
from these damaging molecules. For instance, some
convert peroxides into non-toxic alcohols, thus pro-
tecting cells from membrane damage while others pro-
tect against other types of free radicals. Selenoproteins
are also required to:
Participate in the roduction the white blood cells of
the immune system.
Maintain balanced thyroid gland function.
Promote healthy vision.
Maintain healthy skin and hair.
Protect cells against toxic minerals, such as mercury,
lead, and cadmium.
Help liver function.
Help break down dietary fats.
Maintain elasticity of tissues.
Recent research is also indicative of a physiological
role for selenium, such as maintaining the blood brain
barrier that protects the brain against harmful substan-
ces, with several other studies suggesting other protec-
tive roles. Although many findings are still uncertain, it
is thought that an adequate selenium intake may have
an anti-cancer effect, while protecting against lipid
intake disorders (hyperlipidaemia),hypertensionand
other heart diseases. There are also reports suggestingSelenium