Jan. 8, 2015 -- An avocado a day might help keep bad cholesterol at bay.
Eating one per day as part of a certain heart-healthy, cholesterol-lowering diet can help improve "bad" LDL cholesterol levels in people who are overweight or obese, according to a small study in the Journal of the American Heart Association.
Cholesterol is a type of fat made by the body. It’s key for good health. But high levels, often caused by an unhealthy diet, can raise the risk of heart disease and stroke. Being overweight raises your risk of having high LDL levels.
Avocados are a source of monounsaturated fat, which is good for you when eaten in moderation. They're also rich in vitamins, minerals, fiber, compounds that block cholesterol absorption in the body (phytosterols), and antioxidants that can play a role in preventing cancer and heart disease (polyphenols).
Researchers replaced saturated fatty acids from an average American diet with unsaturated fatty acids from avocados.
Forty-five healthy, overweight, or obese men and women between the ages of 21 and 70 were put on three different cholesterol-lowering diets:
- Lower-fat diet without avocado
- Moderate-fat diet without avocado
- Moderate-fat diet with one avocado per day
Each participant ate each of the three test diets for 5 weeks.
The researchers used Hass avocados -- the ones with bumpy green skin.
People on a moderate-fat diet who ate an avocado every day had lower bad cholesterol levels than those on a similar diet without an avocado a day or those who were on a lower-fat diet.
Compared to the baseline average American diet, LDL was 13.5 points lower after eating the moderate-fat diet that included an avocado. LDL was also lower on the moderate fat diet without the avocado (8.3 points lower) and on the reduced-fat diet (7.4 points lower), though the results weren't as striking as on the avocado diet.
Several other blood measurements were also more favorable after the avocado diet vs. the other two, including: total cholesterol and triglycerides, fat in the blood used to provide energy to the body.
None of the people on the study lost weight.
"Avocados are packed with vitamins, minerals, and potential health benefits. They are rich in monounsaturated fat, which helps reduce levels of ‘bad’ cholesterol within the blood,” says Cara Sloss in an e-mail. She's a spokeswoman for the British Dietetic Association. “They contain more potassium than bananas and are rich in vitamins B, C, and K.
"Research has suggested benefits including a reduced risk of stroke, cancer, and coronary artery disease, along with improved diabetes control. Although there are many benefits, they should be consumed as part of a balanced diet," she says.
An average avocado has 200-300 calories, which is higher than most fruit and vegetables -- so eating too much avocado might lead to weight gain, she cautions.
The study was supported by the Hass Avocado Board (which had no other role in the trial) and the National Center for Advancing Translational Sciences at the National Institutes of Health.