By Andrew M. Seaman
(Reuters Health) – Eating a heart-healthy diet that includes avocados may lower so-called bad cholesterol among otherwise healthy overweight and obese people, according to a new study.
The findings don’t mean people should simply add avocados to their daily diets. Instead, the study’s senior researcher said, the results show that avocados incorporated into healthy diets reduced low-density lipoprotein (LDL) cholesterol.
“They shouldn’t just add an avocado to their diet, but it would be good if they incorporated an avocado into a healthy diet,” said Penny Kris-Etherton, who chairs the American Heart Association’s Nutrition Committee and is a nutrition expert at Pennsylvania State University in University Park.
People should be eating a heart-healthy diet to lower the risk of heart disease, write Kris-Etherton and her colleagues in the Journal of the American Heart Association.
Only 5 to 6 percent of calories should come from saturated fatty acids, which are found in foods like butter, fatty meat and cheese. Instead of saturated fats, people should substitute polyunsaturated and monounsaturated fatty acids.
One earlier trial found that a so-called Mediterranean diet, with monounsaturated fatty acids from extra-virgin olive oil or mixed nuts, cut the risk of major cardiovascular problems like strokes and heart attacks by about 30 percent over five years among older people at an increased risk for those problems, the researchers note.
Avocados are another source of monounsaturated fatty acids, but they also have several other beneficial components, such as vitamins, minerals and fiber, the researchers point out.
For the new study, they assigned 45 otherwise healthy overweight and obese people between ages 21 and 70 to one of three diets aimed at reducing cholesterol, which can collect in the arteries as plaque.
Participants ate a regular American diet for the two weeks before starting the cholesterol-lowering diets. Then they followed either a low-fat diet without avocado, a moderate-fat diet without avocado or a moderate-fat diet with one avocado added every day.
After two weeks on an American diet, the average LDL cholesterol, which is the type that collects in the arteries, was about 128 milligrams per deciliter (mg/dL). An LDL level below 100 mg/dL is considered ideal, according to the U.S. National Institutes of Health.
Five weeks into the assigned diets, average LDL levels had fallen by 7.4 mg/dL in the low-fat without avocado group and 8.3 mg/dL in the moderate-fat without avocado group.
Those on the moderate-fat diet with avocado had the largest change in bad cholesterol, however. Their LDL level fell by 13.5 mg/dL, the researchers found.
A 13.5 mg/dL reduction in LDL cholesterol may be enough keep people from going on cholesterol-lowering medications, Kris-Etherton said. The reduction isn’t nearly as large as what people would see with modern drugs for cholesterol, however.
Kris-Etherton said the study also shows that these heart-healthy diets work at lowering LDL cholesterol with or without avocados.
“A healthy diet works, but there are some added benefits from including the avocado,” she said.
Kate Patton, a preventive-cardiology dietitian at the Cleveland Clinic in Ohio, said the added components of the avocado might have given people in the avocado group an edge over the others, who were also on healthy diets.
“Fiber basically helps you feel full longer and digest a lot slower,” said Patton, who was not involved in the study, adding that it may keep people from eating other things during the day.
Kris-Etherton said it’s also possible that people can benefit from other fruits, vegetables or nuts with properties similar to avocados.
As for people who want to make a change to their diet, she recommends starting by taking a look at what they typically eat.
“Do a sort of self assessment of their diet and say ‘where else can I make changes’ and go from there,” she said.
SOURCE: http://bit.ly/1tPmBlk Journal of the American Heart Association, online January 7, 2015.