LLUAHSC - Spring 2002 Newscope

Newscope

Loma Linda University study of pecans shows that the nuts significantly lower cholesterol

[SCOPE, Spring 2002]

The addition of pecans to the step I diet of the American Heart Association (AHA) significantly lowered cholesterol levels in research subjects, according to a recent study conducted at Loma Linda University and published in the September issue of the Journal of Nutrition.

Researchers at LLU found that a diet containing pecans not only lowered total and LDL—or “bad”—cholesterol significantly more than the AHA diet, but also helped to maintain desirable levels of HDL—or “good”—cholesterol.

These cholesterol findings were presented during a news conference on September 6, held at Loma Linda University Children’s Hospital.

More than 40 news organizations, ranging from newspapers to television, have run stories on the findings.

This is the first controlled crossover metabolic feeding study ever done with pecans. It was conducted by principal investigators Sujatha Rajaram, PhD, assistant professor of public health and preventive medicine, School of Public Health, and Joan Sabaté, MD, DrPH, chair and professor of nutrition, School of Public Health. The study required all research subjects to eat the majority of their meals in a laboratory kitchen over a period of eight weeks. This type of study, known as “the gold standard” among the research community, enables the researchers to eliminate a number of variables which could potentially skew their results.

The tightly monitored crossover study of 23 men and women measured their cholesterol levels while on the step I diet (recommended by the AHA as a first line of therapy for individuals with elevated cholesterol levels) with their cholesterol levels when 20 percent of their calories were replaced with pecans.

In the pecan diet, for instance, pecans were added to cereals, salads, and entrees such as pasta, amounting to about a handful of pecans a day.
“We found that the pecan-containing diet lowered ‘bad’ cholesterol more than twice as much as the AHA step I diet,” says Dr. Rajaram.

Compared to the participants’ baseline cholesterol values, the pecan-containing diet lowered LDL cholesterol levels by 16.5 percent—more than twice as much as the step I diet, which only lowered LDL levels by 6.7 percent. Compared to participants’ cholesterol values while on the AHA step I diet, the pecan diet lowered total cholesterol levels by 11.3 percent—more than twice as much as the step I diet, which only lowered total cholesterol by 5.2 percent.

The U.S. government’s National Cholesterol Education Program notes that for every percent reduction in LDL cholesterol, there is a 1.5 percent reduction in the incidence of coronary heart disease (CHD).

Using this figure, the cholesterol-lowering effects of the pecan diet correspond with a 25 percent decrease in the risk of CHD.

Findings related to HDL levels were significant as well. According to the researchers, the step I diet actually lowered HDL levels—an undesirable result, while the pecan diet increased HDL by 5.6 percent—a desirable result.

“This cholesterol-lowering effect is similar to what is often seen with cholesterol-lowering medications,” notes Dr. Sabaté. “We confirmed that the addition of pecans to a basic heart-healthy diet will yield very desirable blood lipid profiles.”

Dr. Sabaté adds, “Many consumers find low-fat, heart-healthy diets unpalatable and difficult to adhere to.”

Study participants found that the pecans added taste, palatability, and satiety, according to the research team—which should help them keep their resolve to stay with a heart-healthy diet for the long term.

[SCOPE, Spring 2002]