A study published last week in Archives of Internal Medicine found that a diet containing nuts, including pistachios, significantly lowered total and LDL-cholesterol levels, in addition to triglycerides. The 600 subject, 25 clinical trial study, conducted in seven counties, is the most comprehensive study of its kind and further substantiates the evidence that nuts can help reduce the risk of cardiovascular disease.
The report, authored by Dr. Joan Sabaté of Loma Linda University's School of Public Health, and funded by the International Tree Nut Council Nutrition Research & Education Foundation, set out to quantify the cholesterol-reducing benefits of various nuts, such as pistachios, by analyzing previously published human clinical trials.
A Daily Dose of Nuts Offers Significant Results
The authors reviewed the results of 25 human clinical trials published from 1992 through 2007. The analysis included data from 583 men and women, aged 19 to 86 years old. Among the studies, nut consumption ranged from less than one ounce to 4.75 ounces per day. The average daily intake for the meta-analysis was 67 grams per day or 2.4 ounces.
The results found that when 67 grams of nuts were consumed, triglycerides were reduced by 10.2 percent among those with high triglyceride levels at the onset of the study; and total and LDL-cholesterol were lowered by 5.1 percent and 7.4 percent, respectively. Individuals with higher baseline LDL-cholesterol levels also experienced a greater reduction in total and LDL-cholesterol levels compared to those with normal baseline LDL levels. Subjects following a typical Western-diet also experienced a greater reduction in total and LDL-cholesterol levels (-7.4 percent and - 9.6 percent, respectively) compared to a low-fat (-4.1 percent and -6.0 percent, respectively) or a Mediterranean diet (-4.1 percent and -6.0 percent, respectively).
Another important finding was that greater cholesterol lowering benefits were seen in individuals with a lower BMI compared to those with a higher BMI. Additionally, cholesterol levels were reduced in a dose-dependent result, with benefits seen in as low as a one-ounce serving per day; the greatest benefits were seen when 20 percent of calories were consumed daily from nuts. For the typical 2,000-calorie diet, 20 percent equals 400 calories of nuts or 2.4 ounces (about 120) pistachios.
Pistachios' Unique Nutrient Profile Provides "Hearty" Promise
"Enjoying a handful or two of in-shell pistachios may provide significant heart health benefits," said Martin Yadrick, M.B.A., R.D., immediate past-president of the American Dietetic Association. "They are known to also improve blood vessel function, blood sugar control, act as potent antioxidant and offer weight management benefits, all of which are important for improving heart health."
With more than 30 different vitamins, minerals and beneficial phytonutrients, in-shell pistachios are a nutrient-rich snack. In fact, pistachios provide more potassium and phytosterols than any other nut and are the only nut to contain the carotenoids, lutein and zeaxanthin. They also have one of the highest antioxidant capacities of all nuts.
Explore further: Survey indicates willingness of general population to donate tissue samples to biobank