Eating an avocado a day along with a moderate-fat, cholesterol-lowering diet may effectively decrease LDL and non-HDL cholesterol in overweight patients, according to a new study published in the Journal of the American Heart Association.
To reduce the risk for cardiovascular disease (CVD), experts recommend replacing saturated fats with monounsaturated and polyunsaturated fatty acids. Avocados are a nutrient-dense source of monounsaturated fatty acids, but few studies have evaluated avocados’ effect on lipid/lipoprotein profile.
The researchers wanted to look at how avocados affected lipid risk factors compared with another moderate-fat diet (where monounsaturated fatty acids were provided by high oleic acid oils rather than avocados) and a lower-fat diet.
The study included 45 overweight or obese participants aged 21 to 70 years who were otherwise healthy. Before beginning the cholesterol-lowering diets, participants ate average American diets consisting of 34% of calories from fat, 51% from carbohydrates and 16% from protein.
Each participant then consumed three different diets in a randomized order, with each diet lasting a period of 5 weeks: a lower-fat diet without avocado (24% of calories as fat, 11% of which were monounsaturated fatty acids), a moderate-fat diet without avocado and a moderate-fat diet with one avocado per day. For both of the moderate-fat diets, 34% of calories were from fat, with 17% of those coming from monounsaturated fatty acids.
Compared with the baseline average American diet, all three diets significantly lowered LDL cholesterol. The avocado diet produced the most dramatic results, reducing LDL by 13.5 mg/dL compared with 8.3 mg/dL with the moderate-fat diet without avocado and 7.4 mg/dL with the lower-fat diet.
The avocado diet was also the most effective in lowering non-HDL cholesterol, yielding a 14.6-mg/dL reduction compared with an 8.7-mg/dL reduction with the moderate-fat diet and a 4.8-mg/dL reduction with the lower-fat diet.
In addition to being most effective at lowering LDL and non-HDL cholesterol, the avocado diet was the only diet that significantly decreased LDL particle number (–80.1 nmol/L), small dense LDL cholesterol (–4.1 mg/dL) and the ratio of LDL/HDL (–6.6%) from the baseline diet.
“This was a controlled feeding study, but that is not the real-world — so it is a proof-of-concept investigation. We need to focus on getting people to eat a heart-healthy diet that includes avocados and other nutrient-rich food sources of better fats,” study researcher Penny M. Kris-Etherton, PhD, RD, of Pennsylvania State University in University Park, said in a press release.
The results of this study indicate that the bioactive compounds in avocados have additional benefits beyond their monounsaturated fatty acid content. The researchers noted that the participants in this study did not experience weight loss, so the diet would be best suited to people looking to lower their CVD risk without necessarily losing weight.