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The Efficacy of Behavioral Interventions to Modify Dietary Fat and Fruit and Vegetable Intake: A Review of the Evidence

https://doi.org/10.1006/pmed.2002.1028Get rights and content

Abstract

Background. The evidence suggesting that nutrition, particularly dietary saturated fat and fruit and vegetable intake, is related to chronic disease risk has prompted considerable research on behavioral interventions focusing on dietary change. No clear understanding has emerged, however, of the degree to which these interventions can materially influence dietary change, or the types of intervention that are most effective and for whom. Therefore, the primary objective of the current study was to evaluate the overall effectiveness of behavioral dietary interventions in promoting dietary change related to chronic disease risk reduction. A secondary goal was to explore the relative effectiveness of specific intervention features and among different population subgroups.

Methods. We conducted an evidence-based review and secondary analysis of existing literature. Our data sources included reports of randomized controlled trials and other study designs identified from multiple searches of MEDLINE, EMBASE, PsycINFO, CINAHL, AGELINE, and AGRICOLA. We included all studies on humans (including children, adolescents, and adults) published in English since 1975 that had been conducted in North America, Europe, or Australia; that had sample sizes of at least 40 subjects at follow-up; that were not based on controlled diets; and that otherwise met inclusion criteria. Through dual review, we abstracted detailed information on study characteristics, methodology, and outcomes relating to consumption of fruits, vegetables, and fats.

Results. From 907 unduplicated articles originally identified, we retained 104 articles reporting on 92 independent studies. The studies were similarly successful in reducing intake of total and saturated fat, and increasing fruit and vegetable intake. More than three-quarters of the studies (17 of the 22 reporting results for fruit and vegetable intake) reported significant increases in fruit and vegetable intake, with an average increase of 0.6 servings per day. Similar consistent decreases were seen in intake of saturated fat and total fat (7.3% reduction in the percentage of calories from fat). Interventions appeared to be more successful at positively changing dietary behavior among populations at risk of (or diagnosed with) disease than among general, healthy populations. Two intervention components seemed to be particularly promising in modifying dietary behavior—goal setting and small groups.

Conclusions. The majority of the interventions reviewed resulted in meaningful improvements in dietary factors behaviors associated with the prevention of chronic disease, particularly among individuals at elevated disease risk. The lack of similarity across studies in outcome measures, study design, analysis strategy, and intervention technique hampered our ability to draw broad conclusions about the most effective behavioral dietary interventions, but our findings offer insight into intervention components that may hold promise for future research efforts.

References (140)

  • DD Gorder et al.

    Dietary intake in the Multiple Risk Factor Intervention Trial (MRFIT): nutrient and food group changes over 6 years

    J Am Diet Assoc

    (1986)
  • H Lee-Han et al.

    Compliance in a randomized clinical trial of dietary fat reduction in patients with breast dysplasia

    Am J Clin Nutr

    (1988)
  • ML Burr et al.

    Effects of changes in fat, fish, and fibre intakes on death and myocardial reinfarction: diet and reinfarction trial (DART)

    Lancet

    (1989)
  • D Ornish et al.

    Can lifestyle changes reverse coronary heart disease? The Lifestyle Heart Trial

    Lancet

    (1990)
  • RE Glasgow et al.

    Improving self-care among older patients with type II diabetes: the ‘Sixty Something …’ Study

    Patient Educ Counsel

    (1992)
  • AR Kristal et al.

    Long-term maintenance of a low-fat diet: durability of fat-related dietary habits in the Women's Health Trial

    J Am Diet Assoc

    (1992)
  • JH Laitinen et al.

    Impact of intensified dietary therapy on energy and nutrient intakes and fatty acid composition of serum lipids in patients with recently diagnosed non-insulin-dependent diabetes mellitus

    J Am Diet Assoc

    (1993)
  • GE McKeown-Eyssen et al.

    A randomized trial of a low fat high fibre diet in the recurrence of colorectal polyps. Toronto Polyp Prevention Group

    J Clin Epidemiol

    (1994)
  • T Rankinen et al.

    Blood coagulation and fibrinolytic factors are unchanged by aerobic exercise or fat modified diet. Randomized clinical trial in middle-aged men

    Fibrinolysis

    (1994)
  • S Renaud et al.

    Cretan Mediterranean diet for prevention of coronary heart disease

    Am J Clin Nutr

    (1995)
  • L Simkin-Silverman et al.

    Prevention of cardiovascular risk factor elevations in healthy premenopausal women

    Prev Med

    (1995)
  • RE Glasgow et al.

    Long-term effects and costs of brief behavioural dietary intervention for patients with diabetes delivered from the medical office

    Patient Educ Counsel

    (1997)
  • JC Bakx et al.

    Long-term effect of nutritional counseling: a study in family medicine

    Am J Clin Nutr

    (1997)
  • PA Dyson et al.

    The Fasting Hyperglycaemia Study: II. Randomized controlled trial of reinforced healthy-living advice in subjects with increased but not diabetic fasting plasma glucose

    Metabolism

    (1997)
  • CA Cancer J Clinicians

    (1996)
  • U.S. Department of Agriculture and the U.S. Department of Health and Human Services, Nutrition and your health, Dietary...
  • JAMA

    (2001)
  • U.S. Department of Health and Human Services. Healthy people 2010: understanding and improving health and objectives...
  • National Institutes of Health, National Heart, Lung, and Blood Institute, National High Blood Pressure Education...
  • Diabetes Care

    (2000)
  • Committee on Diet and Health, Food and Nutrition Board, Commission on Life Sciences, National Research Council, Diet...
  • World Cancer Research Fund and American Institute for Cancer Research, Food, nutrition and the prevention of cancer: a...
  • M Lipkin et al.

    Dietary factors in human colorectal cancer

    Annu Rev Nutr

    (1999)
  • AR Ness et al.

    Fruit and vegetables, and cardiovascular disease: a review

    Int J Epidemiol

    (1997)
  • MR Law et al.

    By how much does fruit and vegetable consumption reduce the risk of ischaemic heart disease?

    Eur J Clin Nutr

    (1998)
  • A Schatzkin et al.

    Lack of effect of a low-fat, high-fiber diet on the recurrence of colorectal adenomas. Polyp Prevention Trial Study Group

    N Engl J Med

    (2000)
  • SA Smith-Warner et al.

    Intake of fruits and vegetables and risk of breast cancer: a pooled analysis of cohort studies

    JAMA

    (2001)
  • R Doll et al.

    The causes of cancer: quantitative estimates of avoidable risks of cancer in the United States today

    J Natl Cancer

    (1981)
  • JD Potter

    Nutrition and colorectal cancer

    Cancer Causes Control

    (1996)
  • JC LaRosa et al.

    The cholesterol facts. A summary of the evidence relating dietary fats, serum cholesterol, and coronary heart disease. A joint statement by the American Heart Association and the National Heart, Lung, and Blood Institute. The Task Force on Cholesterol Issues, American Heart Association

    Circulation

    (1990)
  • A Ascherio et al.

    Trans fatty acids and coronary heart disease

    N Engl J Med

    (1999)
  • S Ebrahim et al.

    Systematic review of randomised controlled trials of multiple risk factor interventions for preventing coronary heart disease

    BMJ

    (1997)
  • L Hooper et al.

    Dietary fat intake and prevention of cardiovascular disease: systematic review

    BMJ

    (2001)
  • K Glanz

    Behavioral research contributions and needs in cancer prevention and control: dietary change

    Prev Med

    (1997)
  • I Contento et al.

    Special issue: the effectiveness of nutrition education and implications for nutrition education policy, programs, and research: a review of research

    J Nutr Educ

    (1995)
  • CT Orleans

    Promoting the maintenance of health behavior change: recommendations for the next generation of research and practice

    Health Psychol

    (2000)
  • Glanz, K, Lewis, F, M, Rimer, B, KE, Health behavior and health education: theory, research, and practice, San...
  • WM Verschuren et al.

    Serum total cholesterol and long-term coronary heart disease mortality in different cultures. Twenty-five-year follow-up of the seven countries study

    JAMA

    (1995)
  • JS Carter et al.

    Non-insulin-dependent diabetes mellitus in minorities in the United States

    Ann Intern Med

    (1996)
  • SK Kumanyika et al.

    Models for dietary and weight change in African–American women: identifying cultural components

    Ethnic Dis

    (1992)
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    This study was developed by the RTI/UNC Evidence-based Practice Center under contract to the Agency for Healthcare Research and Quality (Contract No. 290-97-0011), Rockville, MD. We acknowledge the assistance of Jacqueline Besteman, J.D., M.A., the AHRQ Program Officer for the Evidence-based Practice Program; Kate Rickard, M.P.A., the AHRQ task order officer for this project; and Robert Croyle, Ph.D., the liaison contact for the National Cancer Institute. We appreciate the considerable help of the members of the technical expert advisory group: Cheryl Achterberg, Ph.D., The Pennsylvania State University, University Park, PA; Tom Baranowski, Ph.D., Baylor College of Medicine, Houston, TX; Susan J. Curry, Ph.D., Group Health Cooperative of Puget Sound, Seattle, WA; Arthur Evans, M.D., M.P.H., Cook County Hospital, Chicago, IL; Karen Glanz, Ph.D., M.P.H., University of Hawaii, Honolulu, HI; Russell E. Glasgow, Ph.D., AMC Cancer Research Center, Denver, CO; Shiriki Kumanyika, Ph.D., M.P.H., University of Pennsylvania School of Medicine, Philadelphia, PA; Rev. Joseph C. Paige, Ed.D., Ed.M., M.Div., Shaw Divinity School, Raleigh, NC. We thank the following staff from the University of North Carolina at Chapel Hill: Timothy S. Carey, M.D., M.P.H., Senior medical consultant; Lenore Arab, Ph.D., scientific expert; Marci Campbell, Ph.D., R.D., scientific expert; Tom Keyserling, M.D., M.P.H., medical consultant; Anne Jackman, M.S.W., project administrator; Sue Tolleson-Rinehart, Ph.D., author of the project's dissemination and implementation report; and Lynn Whitener, Dr.P.H., MSLS, senior librarian and information specialist. We thank Victor Hasselblad, Ph.D., of Duke Clinical Research Institute for expertise in meta-analytic methods. We also thank the following staff of the Research Triangle Institute: Norma Gavin, Ph.D., senior research economist; Christopher Wiesen, Ph.D., research analyst; Cristina Garces, B.A., project administrator; Linda Fonville and Loraine Monroe, for excellent word processing support; Linda Lux, M.P.A., RTI-UNC EPC program manager; and Richard Strowd, J.D., and Tim Weinzapfel for skilled contract administration assistance.

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    To whom reprint requests should be addressed at Schools of Public Health and Medicine, University of North Carolina at Chapel Hill, CB No. 7400, Chapel Hill, NC 27599-7400. Fax: (919) 966-3374. E-mail: [email protected].

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