Original Article

Healthcare Providers’ Knowledge of Diets and Dietary Advice

Authors: Sonali Arora, MD, Auras R. Atreya, MD, Adam M. Bernstein, MD, ScD, Reva Kleppel, MSW, MPH, Jennifer Friderici, MS, Sarah Schramm, MA, Tara Lagu MD, MPH, Michael B. Rothberg, MD, MPH

Abstract

Objectives: Little is known about healthcare providers’ knowledge of dietary evidence or about what dietary advice providers offer to patients. The objective of our study was to determine which diets providers recommended to patients and providers’ beliefs about the evidence behind those recommendations.

Methods: This was a 22-question cross-sectional survey conducted between February 2013 and September 2013, in 45 ambulatory practices within two health systems. Attending physicians, housestaff, and advanced practitioners in internal medicine, medicine-pediatrics, family medicine, cardiology, and endocrinology practices were audited. Providers’ attitudes, perceptions, and beliefs about diet modification were collected. Knowledge scores were constructed based on the number of correct responses to specific questions.

Results: Of 343 provider responses, largely from primary care specialties (n = 3027, 90%), the top dietary recommendations were low-salt diet (71%) for hypertension, low-carbohydrate diet (64%) for uncontrolled diabetes mellitus, low saturated fat diet (73%) for dyslipidemia, low-calorie diet (72%) for obesity, and low saturated fat diet (63%) for coronary heart disease. Providers believed that 51% of diet recommendations were supported by randomized trial evidence when they were not. Respondents’ overall knowledge of randomized trial evidence for dietary interventions was low (mean [standard deviation] knowledge score 44.3% [22.4%], range 0.0%–100.0%). The survey study from two health systems, using a nonvalidated survey tool limits external and internal validity.

Conclusions: Providers report recommending different diets depending on specific risk factors and generally believe that their recommendations are evidence based. Substantial gaps between their knowledge and the randomized trial evidence regarding diet for disease prevention remain.

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References

1. Bruer RA, Schmidt RE, Davis H. Nutrition counseling--should physicians guide their patients? Am J Prev Med 1994;10:308-311.
 
2. Devries S, Dalen JE, Eisenberg DM, et al. A deficiency of nutrition education in medical training. Am J Med 2014;127:804-806.
 
3. Estruch R,Ros E, Salas-Salvado J, et al. Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med 2013;368:1279-1290.
 
4. Salas-Salvado J, Bullo M, Estruch R, et al. Prevention of diabetes with Mediterranean diets: a subgroup analysis of a randomized trial. Ann Intern Med 2014;160:1-10.
 
5. Shai I, Schwarzfuchs D, Henkin Y, et al. Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. N Engl J Med 2008;359:229-241.
 
6. Appel LJ, Moore TJ, Obarzanek E, et al. A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group. N Engl J Med 1997;336:1117-1124.
 
7. Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH-Sodium Collaborative Research Group 2001;344:3-10.
 
8. Azadbakht L, Fard NR, Karimi M, et al. Effects of the Dietary Approaches to Stop Hypertension (DASH) eating plan on cardiovascular risks among type 2 diabetic patients: a randomized crossover clinical trial. Diabetes Care 2011;34:55-57.
 
9. de Lorgeril M, Salen P, Martin JL, et al. Mediterranean diet, traditional risk factors, and the rate of cardiovascular complications after myocardial infarction: final report of the Lyon Diet Heart Study. Circulation 1999;99:779-785.
 
10. Estruch R, Martinez-Gonzalez MA, Corella D, et al. Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomized trial. Ann Intern Med 2006;145:1-11.
 
11. He FJ, Li J, Macgregor GA. Effect of longer-term modest salt reduction on blood pressure. Cochrane Database Syst Rev 2013;4:CD004937.
 
12. Gardner CD, Kiazand A, Alhassan S, et al. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA 2007;297:969-977.
 
13. Appel LJ, Sacks FM, Carey VJ, et al. Effects of protein, monounsaturated fat, and carbohydrate intake on blood pressure and serum lipids: results of the OmniHeart randomized trial. JAMA 2005;294:2455-2464.
 
14. Hypertension Prevention Trial Research Group. The Hypertension Prevention Trial: three-year effects of dietary changes on blood pressure. Arch Intern Med 1990;150:153-162.
 
15. Toobert DJ, Glasgow RE, Strycker LA, et al. Biologic and quality-of-life outcomes from the Mediterranean Lifestyle Program: a randomized clinical trial. Diabetes Care 2003;26:2288-2293.
 
16. Esposito K, Marfella R, Ciotola M, et al. Effect of a Mediterranean-style diet on endothelial dysfunction and markers of vascular inflammation in the metabolic syndrome: a randomized trial. JAMA 2004;292:1440-1446.
 
17. Howard BV, Manson JE, Stefanick ML, et al. Low-fat dietary pattern and weight change over 7 years: the Women’s Health Initiative Dietary Modification Trial. JAMA 2006;295:39-49.
 
18. Foster GD, Wyatt HR, Hill JO, et al. A randomized trial of a low-carbohydrate diet for obesity. N Engl J Med 2003;348:2082-2090.
 
19. Stern L, Iqbal N, Seshadri P, et al. The effects of low-carbohydrate versus conventional weight loss diets in severely obese adults: one-year follow-up of a randomized trial. Ann Intern Med 2004;140:778-785.
 
20. Samaha FF, Iqbal N, Seshadri P, et al. A low-carbohydrate as compared with a low-fat diet in severe obesity. N Engl J Med 2003;348:2074-2081.
 
21. Brehm BJ, Seeley RJ, Daniels SR, et al. A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women. J Clin Endocrinol Metab 2003;88:1617-1623.
 
22. Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults--The Evidence Report. National Institutes of Health. Obes Res 1998;6(Suppl 2):51S-209S.
 
23. American Dietetic Association. Nutrition care manual. http://www.nutritioncaremanual.org. Accessed August 8, 2015.
 
24. National Cholesterol Education Program, Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). http://www.nhlbi.nih.gov/files/docs/guidelines/asthgdln.pdf. Accessed September 1, 2012.
 
25. Atkins R. Dr. Atkins’ New Diet Revolution. New York: Simon & Schuster, 1998.
 
26. US Department of Agriculture, US Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th ed. Washington, DC: US Government Printing Office, December 2010.
 
27. He FJ, MacGregor GA. Effect of longer-term modest salt reduction on blood pressure. Cochrane Database Syst Rev 2004;3:CD004937.
 
28. Hu FB. Diet and cardiovascular disease prevention the need for a paradigm shift. J Am Coll Cardiol 2007;50:22-24.
 
29. Kraschnewski JL, Sciamanna CN, Stuckey HL, et al. A silent response to the obesity epidemic: decline in US physician weight counseling. Med Care 2013;51:186-192.
 
30. Heaton PC, Frede SM. Patients’ need for more counseling on diet, exercise, and smoking cessation: results from the National Ambulatory Medical Care Survey. J Am Pharm Assoc (2003) 2006;46:364-369.
 
31. Secker-Walker RH, Morrow AL, et al. Family physicians’ attitudes about dietary advice. Fam Pract Res J 1991;11:161-170.
 
32. Wynn K, Trudeau JD, Taunton K, et al. Nutrition in primary care: current practices, attitudes, and barriers. Can Fam Physician 2010;56:e109-e116.
 
33. Park ER, Wolfe TJ, Gokhale M, et al. Perceived preparedness to provide preventive counseling: reports of graduating primary care residents at academic health centers. J Gen Intern Med 2005;20:386-391.
 
34. Tang JW, Freed B, Baker T, et al. Internal medicine residents’ comfort with and frequency of providing dietary counseling to diabetic patients. J Gen Intern Med 2009;24:1140-1143.
 
35. Kushner RF. Barriers to providing nutrition counseling by physicians: a survey of primary care practitioners. Prev Med 1995;24:546-552.
 
36. Morris NP. The neglect of nutrition in medical education: a firsthand look. JAMA Intern Med 2014;174:841-842.
 
37. Nestle M, Baron RB. Nutrition in medical education: from counting hours to measuring competence. JAMA Intern Med 2014;174:843-844.
 
38. Vetter ML, Herring SJ, Sood M, et al. What do resident physicians know about nutrition? An evaluation of attitudes, self-perceived proficiency and knowledge. J Am Coll Nutr 2008;27:287-298.
 
39. Flynn M, Sciamanna C, Vigilante K. Inadequate physician knowledge of the effects of diet on blood lipids and lipoproteins. Nutr J 2003;2:19.
 
40. Wong S, Derry F, Graham A, et al. An audit to assess awareness and knowledge of nutrition in a UK spinal cord injuries centre. Spinal Cord 2012;50:446-451.
 
41. Ahmadi A, Ershad M, Givzadeh H, Mohammad-Beigi A. General physicians’ knowledge about nutrition in Shiraz, Iran. Pak J Biol Sci 2009;12:981-985.
 
42. Al-Zahrani AM, Al-Raddadi RM. Nutritional knowledge of primary health care physicians in Jeddah, Saudi Arabia. Saudi Med J 2009;30:284-287.
 
43. La Puma J, Szapary P, Maki KC. Physicians recommendations for and personal use of low-fat and low-carbohydrate diets. Int J Obes (Lond) 2005;29:251-253.
 
44. Ward T. Barriers to patients’ heart health beyond physician control. http://www.medscape.com/viewarticle/822143. Published March 20, 2014. Accessed May 27, 2015.
 
45. Evert AB, Boucher JL, Cypress M, et al. Nutrition therapy recommendations for the management of adults with diabetes. Diabetes Care 2014;37(Suppl 1):S120-S143.
 
46. Eckel RH, Jakicic JM, Ard JD, et al. 2013 AHA/ACC guideline on lifestyle management to reduce cardiovascular risk: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation 2014;129(25 Suppl 2):S76-S99.
 
47. Gifford KD. Dietary fats, eating guides, and public policy: history, critique, and recommendations. Am J Med 2002;113(Suppl 9B):89S-106S.