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Diet Modification and Blood Pressure in Young People

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ClinicalTrials.gov Identifier: NCT00005167
Recruitment Status : Completed
First Posted : May 26, 2000
Last Update Posted : February 18, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary:
To determine the effects of diet modification on blood pressure, blood cholesterol, and bone density in healthy young people.

Condition or disease
Cardiovascular Diseases Heart Diseases

Detailed Description:


An inadequate dietary intake of calcium has been postulated to be a factor in the development of essential hypertension, and has long been considered important in the development of osteoporosis among women. Furthermore, animal experiments and limited studies in humans suggest that an increase in the intake of calcium may also have a beneficial effect on blood cholesterol levels. Despite limitations in the research data supporting its benefits, increased calcium intake is being widely advocated to the public and calcium-enriched products are being increasingly purchased and consumed by Americans. The study measured the effects of a modest increase in calcium intake, such as that currently advocated to the general public.

Previous work in the study measured the effects on blood pressures of variations in the dietary intake of sodium and linoleic acid in adolescents at the two New England boarding schools of Phillips Exeter Academy and Phillips Andover Academy. During the first year, dining room food at one school was prepared with 50 percent less sodium; total intake of sodium by students including dining hall food, outside food and snacks was reduced by approximately 35 percent. The other school served as the control. During the second year, the intervention took place at the second school. During the third and fourth years, sodium intake was kept at usual levels while changes were made in food preparation to double the polyunsaturated fatty acid intake from four percent to eight percent of dietary calories. Food diaries, duplicate food samples, and 24-hour urine collections by approximately 200 students at each school were used to monitor dietary modification and student compliance. Weekly blood pressure measurements were performed on the 200 students at each school.


A number of food products were modified to increase the dietary intake of calcium by an average of 500 mg/day. Calcium-enriched foods were served alternately for one school year at each of two colleges. Similar products without added calcium were served during the alternate year. It was postulated that, at the end of the school year, students at the intervention school would have lower systolic blood pressure, lower blood cholesterol, and increased bone density than students at the control school.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

Study Type : Observational
Study Start Date : July 1984
Study Completion Date : December 1991

Information from the National Library of Medicine

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Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria

Ellison RC, Cohn PF: Prevention of Coronary Atherosclerosis. In: Diagnosis and Therapy of Coronary Artery Disease, Second Edition. Boston, Martinus Nijoff, p 283-303, 1985
Capper AL, Witschi J: Schools in the Fire: How to Improve Children's Dietary Habits. Food Management, December, 1986
Ellison RC: Dangers of Screening for Hyperlipidemia in Children (Letter to the Editor). N Engl J Med, 314:1579-1580, 1986
Capper AL, Doane DD: Can a Reduced Sodium Diet Prevent Hypertension? J Nat Assoc College Auxiliary Services, August:47-49, 1987
Korn L, Hosmer DW, Lemeshow S: The Performance of Goodness of Fit Tests for Logistic Regression With Discrete Covariates. Biometrical Journal (in press), 0000
Capper AL, Doane DD: Dining Hall Employees Contribute to Science. College Services Administration (in press), 0000
Capper AL, Witschi JC: Reduced Salt in School Food - Can it Work? J Nat Assoc College Food Services (in press), 0000

ClinicalTrials.gov Identifier: NCT00005167     History of Changes
Other Study ID Numbers: 1041
R01HL032821 ( U.S. NIH Grant/Contract )
First Posted: May 26, 2000    Key Record Dates
Last Update Posted: February 18, 2016
Last Verified: April 2000

Additional relevant MeSH terms:
Cardiovascular Diseases
Heart Diseases