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While cholesterol control is often balanced between statins and lifestyle changes, reducing triglycerides can usually be accomplished with diet and lifestyle changes alone, according to a new scientific statement from the American Heart Association.

"It is especially disconcerting that in the U.S., mean triglyceride levels have risen since 1976, in concert with the growing epidemic of obesity, insulin resistance, and type 2 diabetes mellitus. In contrast, mean low-density lipoprotein cholesterol levels have receded," according to the statement published online April 18 in Circulation.

The researchers analyzed more than 500 international studies from the past 30 years in an effort to update clinicians on the role of triglycerides in the evaluation and management of cardiovascular disease risk.

Led by Michael Miller, MD, director of the Center for Preventive Cardiology at the University of Maryland School of Medicine in Baltimore, the researchers reaffirmed that triglycerides are not directly atherogenic but represent an important biomarker of cardiovascular disease risk.

They suggested that clinicians should better understand the "metabolic pathways of triglyceride-rich particles and the consequences of hypertriglyceridemia," particularly in knowing the "characteristic lipid alterations in diabetes mellitus, lipodystrophic disorders including those seen with HIV, and chronic renal disease."

For those outside the normal range of triglycerides, Miller and colleagues recommend limiting:

• Added sugar to less than 5% to 10% of calories consumed -- about 100 calories per day for women and 150 calories per day for men
• Fructose from both processed foods and naturally occurring foods -- less than 50 to 100 grams per day
• Saturated fat to less than 7 percent of total calories
• Trans fat to less than 1 percent of total calories

Additionally, for persons with especially high triglyceride levels -- greater than 500 mg/dL -- Miller et al. recommend abstaining from alcohol to guard against pancreatitis.

The recommendations encourage all patients with triglyceride levels in the borderline to high range (150 to 199 mg/dL) or greater to incorporate physical activities of at least moderate intensity (such as brisk walking) for a total of at least 150 minutes per week, because these activities may contribute an additional 20% to 30% triglyceride-lowering effect.

"Overall, the treatment of elevated triglyceride levels focuses on intensive therapeutic lifestyle change," they wrote.

"For example, a 5% to 10% reduction in body weight anticipates a triglyceride-lowering response of 20%. Further offsets in carbohydrate calories by reducing added sugars and fructose while increasing unsaturated fat intake may contribute an additional 10% to 20% reduction in triglyceride levels."

Further reduction or elimination of trans fats and increased consumption of marine-based omega-3 products, along with aerobic exercise, will result in optimal lowering of triglycerides.

"Taken together, reductions of 50% or more in triglyceride levels may be attained through intensive therapeutic lifestyle change," they concluded.

The statement also concludes that the use of medications to lower triglycerides "is still lacking crucial clinical trial evidence." Except to prevent pancreatitis for those with triglyceride levels above 500 mg/dL, the recommendations are to avoid triglyceride-lowering medications but to review medication lists for drugs that might be raising triglycerides.

Triglyceride testing is traditionally taken after a 12-hour fast. The authors suggest using non-fasting triglyceride testing as an initial screen. Although the cutoff for elevated triglycerides remains at 150 mg/dL, a new optimal level of 100 mg/dL has now been set to acknowledge the protective benefit of lifestyle in metabolic health, the authors noted.

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