Despite major progress in cardiovascular research in the past 20 years, cardiovascular disease (CVD) remains the leading cause of death in America, with the majority of our healthcare dollars being spent at the end stage of the disease.1,2
The question is, why is this disease still the leading cause of death, when the disease is largely preventable through lifestyle changes and medical therapy? We are fortunate to live in an age where statins and antiplatelet agents—in conjunction with lifestyle therapy—drastically improve cardiovascular outcomes, and are being put to the test against more invasive approaches.3-8 Diets have been shown to improve outcomes, even when added to an optimal medical therapy regimen. Why, then, is there not more of a focus in healthcare delivery on the importance of diet in CVD?
Dietary Intake and CVD Risk
Many years of epidemiologic data have illustrated correlations between “heart healthy” eating patterns and lower incidences of CVD among specific populations.9-11 Although there may be other factors contributing to health, the correlations have been observed across varied populations over time. There are more than adequate data available from epidemiologic studies demonstrating that a high intake of fruits, vegetables, whole grains, fish, low-fat dairy, nuts, and olive oil is associated with low incidences of CVD.12-14 There is also evidence that consumption of trans fats is associated with an increased risk for CVD,15,16 and that red meat consumption is associated not only with increased CVD, but with increased incidences of cancer and overall death.17
To date, several diets have demonstrated beneficial effects on cardiovascular risk. The DASH (Dietary Approaches to Stop Hypertension) diet, which is rich in fruits and vegetables, low-fat dairy, and whole grains, has been shown to be effective for lowering blood pressure, and the current American College of Cardiology/American Heart Association lifestyle management guidelines support its use.18-20 Epidemiologic data have illustrated that populations historically known to follow a Mediterranean diet, and those adhering to a Mediterranean diet, have lower incidences of CVD21; randomized controlled data support its use as well.22
The Lyon Diet Heart Study is one of the first trials to show the benefits of a Mediterranean diet in reducing cardiac deaths and nonfatal myocardial infarctions (MIs) in post-MI patients compared with a postinfarct prudent diet, despite similar lipid lowering, blood pressure reduction, and weight loss in both study groups, also suggesting an independent mechanism of benefit.22,23 The more recent PREDIMED trial showed that a Mediterranean diet, which predominantly differed from the control group’s diet because of the increased use of nuts and olive oil, improved cardiovascular outcomes by 30%—more than many of the medical therapies that we prescribe.24
Guidelines and Recommendations
Although prior National Cholesterol Education Program guidelines included the limitation of dietary cholesterol,25 more recent guidelines have abandoned these recommendations because of inadequate evidence.26,27 A recent meta-analysis has also questioned whether saturated fat causes CVD26. Even though a causal role may not have been previously shown in a randomized trial, it is difficult to ignore epidemiologic correlations and the fact that saturated fat raises low-density lipoprotein cholesterol is a key culprit in CVD.
Questions also remain about whether the true culprits behind CVD are sugar and processed carbohydrates, because of their known correlation with diabetes, obesity, metabolic syndrome, and dyslipidemia. A prior emphasis on a “low-fat” versus “good fat” diet may also have led to the current unprecedented rates of diabetes and obesity in our country.
Providing Dietary Education and Counseling
Although questions certainly remain about the exact balance of macronutrients, and the benefits of specific food groups with respect to cardiovascular health, there is enough evidence available to date to justify a change in the current paradigm of dietary counseling.
As ongoing research continues in this exceptionally vital area, we need to move dietary education to the forefront of clinical care. Team-based approaches, dietary assessment, dietary counseling, and behavioral programs should be the standard of care in our health system. We can empower patients to make lifestyle changes that will translate to improved health, extending far beyond cardiovascular benefits. However, to effect meaningful change to the current system, clinical care providers at all levels need to be trained adequately about dietary counseling, and reinforce the importance of this aspect of healthcare with patients.
The conversation needs to be initiated by physicians, physician extenders, nurses, and pharmacists who can begin the education process and use all necessary resources for effecting a behavioral change. Using the expertise of dietitians and ongoing behavioral programs is essential to this process; the greatest success has been noted historically in patients with the most ongoing follow-up. A renewed focus on diet for cardiovascular health is needed now.
Hippocrates possibly explained it best when he said, “If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health.”28
- Roger VL, Go AS, Lloyd-Jones DM, et al. Heart disease and stroke statistics—2011 update: a report from the American Heart Association. Circulation. 2011;123:e18-e209.
- Cannon CP. Cardiovascular disease and modifiable cardiometabolic risk factors. Clin Cornerstone. 2007;8:11-28.
- ClinicalTrials.gov International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA). https://clinicaltrials.gov/ct2/show/NCT01471522. Updated October 8, 2015. Accessed October 19, 2015.
- Taylor FC, Huffman M, Ebrahim S. Statin therapy for primary prevention of cardiovascular disease. JAMA. 2013;310:2451-2452.
- Mihaylova B, Emberson J, et al; Cholesterol Treatment Trialists’ (CTT) Collaborators. The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials. Lancet. 2012;380:581-590.
- Ascunce RR, Berger JS, Weintraub HS, Schwartzbard A. The role of statin therapy for primary prevention: what is the evidence? Curr Atheroscler Rep. 2012. [Epub ahead of print]
- Brotons C, Benamouzig R, Filipiak KJ, et al. A systematic review of aspirin in primary prevention: is it time for a new approach? Am J Cardiovasc Drugs. 2015;15:113-133.
- Fuster V, Sweeny JM. Aspirin: a historical and contemporary therapeutic overview. Circulation. 2011;123:768-778.
- Fidanza F, Alberti A, Lanti M, Menotti A. Mediterranean diet score: correlation with 25-year mortality from coronary heart disease in the Seven Countries Study. Nutr Metab Cardiovasc Dis. 2004;14:397.
- Guo J, Li W, Wang Y, et al. Influence of dietary patterns on the risk of acute myocardial infarction in China population: the INTERHEART China study. Chin Med J (Engl). 2013;126:464-470.
- Papandreou C, Tuomilehto H. Coronary heart disease mortality in relation to dietary, lifestyle and biochemical risk factors in the countries of the Seven Countries Study: a secondary dataset analysis. J Hum Nutr Diet. 2014;27:168-175.
- Dauchet L, Amouyel P, Hercberg S, Dallongeville J. Fruit and vegetable consumption and risk of coronary heart disease: a meta-analysis of cohort studies. J Nutr. 2006;136(10):2588-2593.
- Hu FB. Plant-based foods and prevention of cardiovascular disease: an overview. Am J Clin Nutr. 2003;78(3 Suppl):544S-551S.
- Mozaffarian D, Appel LJ, Van Horn L. Components of a cardioprotective diet: new insights. Circulation. 2011;1232870-2891.
- Ascherio A, Katan MB, Zock PL, et al. Trans fatty acids and coronary heart disease. N Engl J Med. 1999;340:1994-1998.
- Willett WC, Mozaffarian D. Trans fats in cardiac and diabetes risk: An overview. Curr Cardio Risk Rep. 2007;1:16-23.
- Pan A, Sun Q, Bernstein AM, et al. Red meat consumption and mortality: results from 2 prospective cohort studies. Arch Intern Med. 2012;172:555-563.
- 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. N Engl J Med. 2001;344:3-10.
- 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.
- 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(Suppl 2):S76-S99.
- Mitrou PN, Kipnis V, Thiébaut AC, et al. Mediterranean dietary pattern and prediction of all-cause mortality in a US population: results from the NIH-AARP Diet and Health Study. Arch Intern Med. 2007;167:2461-2468.
- de Lorgeril M, Renaud S, Mamelle N, et al. Mediterranean alpha-linolenic acid-rich diet in secondary prevention of coronary heart disease. Lancet. 1994;343:1454-1459.
- de Lorgeril M, Salen P. Mediterranean diet in secondary prevention of CHD. Public Health Nutr. 2011;14:2333-2337.
- Estruch R, Ros E, Salas-Salvadó J, et al. Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med. 2013;368:1279-1290.
- American Heart Association Nutrition Committee, Lichtenstein AH, Appel LJ, et al. Diet and lifestyle recommendations revision 2006: a scientific statement from the American Heart Association Nutrition Committee. Circulation. 2006;114:82-96.
- Berger S, Raman G, Vishwanathan R, et al. Dietary cholesterol and cardiovascular disease: a systematic review and meta-analysis. Am J Clin Nutr. 2015;102:276-294.
- Chowdhury R, Warnakula S, Kunutsor S, et al. Association of dietary, circulating, and supplement fatty acids with coronary risk: a systematic review and meta-analysis. Ann Intern Med. 2014;160:398-406.
- Hippocrates. Hippocratic Writings. Chicago: Encyclopedia Britannica; 1955.