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New Dietary Guidelines Might Exclude Cholesterol Limit

By Judith C. Thalheimer, RD, LDN

Decades-long recommendations to limit dietary cholesterol may soon change. Every five years, the US Department of Agriculture and Department of Health and Human Services release an update of the Dietary Guidelines for Americans (DGA). These recommendations, which influence everything from school meal nutrition standards to the USDA's MyPlate,1 are based on a review of the latest research compiled by the Dietary Guidelines Advisory Committee (DGAC).

In a recently released report offering recommendations for the 2015 DGA, the DGAC concluded, "Cholesterol is not a nutrient of concern for overconsumption."2 If the 2015 DGA, due out this fall, includes this advice, no longer will there be a recommended upper limit for dietary cholesterol intake. "This is a very controversial statement," says Penny Kris-Etherton, PhD, RD, FAHA, FNLA, CLS, distinguished professor of nutrition at Penn State University. "There were a lot of comments on both sides of the issue at the DGAC meeting."

Controversial Proposal
The 2010 DGAs advise limiting dietary cholesterol intake to less than 300 mg per day.3 In making its recommendation to eliminate this limit in the 2015 DGA, the DGAC cites an American Heart Association/American College of Cardiology (AHA/ACC) report that concluded there's insufficient evidence to show that restricting dietary cholesterol lowers low-density lipoproteins (LDL-C) in the blood.4 Other prominent health advocacy groups, such as the Center for Science in the Public Interest and Physicians Committee for Responsible Medicine, disagree. They believe the evidence does support dietary cholesterol restrictions.5,6

The fact that elevated serum cholesterol is a major risk factor for cardiovascular disease (CVD) isn't in dispute. Higher serum LDL-C correlates to higher CVD risk.7 The question is whether eating a large amount of high-cholesterol foods leads to high serum LDL-C, and whether limiting dietary cholesterol intake lowers serum LDL-C. Research is more definitive about saturated fat and trans fat, both of which can raise LDL-C levels and CVD risk.2,4 While the DGAC recommendations suggest removing dietary cholesterol limits, they continue to list saturated fat as a "nutrient of concern for overconsumption" and state that decreasing saturated fat intake will lead to lower CVD risk.2

Many high-cholesterol foods also contain high levels of saturated fat.1 Arguments against eliminating longstanding advice to limit dietary cholesterol intake include a concern that the public will see this as a license to consume unlimited foods such as dairy products, meat, and some processed foods, which are high in both cholesterol and saturated fat.6 Other foods, such as eggs and seafood, including shrimp and lobster, are high in cholesterol but not saturated fat.7 In 2013, Shin and colleagues published a review and meta-analysis looking at egg consumption and CVD. Individuals who ate egg at least once per day didn't have a significantly higher risk of CVD than those who never consumed egg.8

What Nutrition Professionals Should Do
Cholesterol is essential to human physiology, but since the body manufactures all the cholesterol it needs, dietary cholesterol is unnecessary for survival. Besides diet, many factors contribute to high blood cholesterol levels, including genetics, overweight/obesity, inactivity, and age, making serum cholesterol management a multifactorial problem.9

From a diet perspective, the AHA/ACC guidelines recommend lowering LDL-C by limiting saturated fat to 5% to 6% of calories, reducing trans fat intake, and following a calorie-appropriate diet based on vegetables, fruits, and whole grains; low-fat dairy, poultry, fish, legumes, nontropical vegetable oils, and nuts; with limited sweets, sugar-sweetened beverages, and red meats.4 The DGAC report encourages a similar dietary pattern to decrease CVD risk, but suggests daily intake of less than 10% of total calories from saturated fat.2

It's uncertain whether the 2015 DGAs will include the DGAC's recommendation to remove the limit on dietary cholesterol intake, putting high cholesterol/low-saturated fat foods, such as eggs, shellfish, and organ meats, back on the menu. If dietary cholesterol recommendations are changed, it's unclear whether that change will apply to high-risk individuals, such as people already diagnosed with heart disease or those with certain CVD risk factors such as diabetes. "It's important for nutrition professionals to stay tuned on this issue," Kris-Etherton says. "There will be more information coming out, and there's certain to be a lot of discussion."

— Judith C. Thalheimer, RD, LDN, is a freelance nutrition writer, a community educator, and the principal of JTRD Nutrition Education Services.

References
1. American Heart Association. New federal guidelines may lift dietary cholesterol limits. American Heart Association website. http://blog.heart.org/new-federal-guidelines-may-lift-dietary-cholesterol-limits/. February 12, 2015.

2. United States Department of Agriculture. Scientific Report of the 2015 Dietary Guidelines Advisory Committee. http://www.health.gov/dietaryguidelines/2015-scientific-report/PDFs/Scientific-Report-of-the-2015-Dietary-Guidelines-Advisory-Committee.pdf). February 2015.

3. US Department of Agriculture and US Department of Health and Human Services. Dietary Guidelines for Americans 2010. 7th Edition, Washington, DC: U.S. Government Printing Office, December 2010.

4. Stone NJ, Robinson JG, Lichtenstein AH, et al. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014;129:S76-S99.

5. Jacobson MF. Dietary Guidelines Advice, Mostly Unchanged, is Mostly Praised by CSPI. Center for Science in the Public Interest website. http://cspinet.org/new/201502192.html. February 19, 2015.

6. Templeton D. Scientists debate impact of removing guidelines for dietary cholesterol. Chicago Tribune website. http://www.chicagotribune.com/lifestyles/health/sns-tns-bc-health-cholesterol-guide-20150413-story.html#page=1. April 13, 2015.

7. Kanter MM, Kris-Etherton PM, Fernandez ML, Vickers KC, Katz DL. Exploring the Factors That Affect Blood Cholesterol and Heart Disease Risk: Is Dietary Cholesterol as Bad for You as History Leads Us to Believe? Adv Nutr. 2012;(3): 711-717.

8. Shin JY, Xun P, Nakamura Y, He K. Egg consumption in relation to risk of cardiovascular disease and diabetes: a systematic review and meta-analysis. Am J Clin Nutr. 2013;98(1):146-159.

9. American Heart Association. Q & A about federal nutrition panel's advice on dietary cholesterol. American Heart Association website. http://blog.heart.org/qa-federal-nutrition-panels-advice-dietary-cholesterol/. February 12, 2015.

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