Avocado a day could keep bad cholesterol at bay and reduce heart attack risk

• Daily helping can replace unhealthy fats in the diet with a healthier version
• Experts: Most people don't know how to incorporate avocado into diet
• Researchers used Hass avocados, those with bumpy green skin

By Jenny Hope Medical Correspondent For The Daily Mail

Published: 16:00 EST, 7 January 2015 | Updated: 00:58 EST, 8 January 2015

An avocado a day could help improve bad cholesterol levels, claim researchers.

The ‘avocado diet’ also improves other blood fat scores linked to heart disease – even in the overweight.

Researchers say a daily helping of avocado can replace unhealthy fats in the diet with a healthier version.

A daily avocado appears to lower levels of 'bad' cholesterol in the body, reducing the risk of a heart attack

Study leader Penny Kris-Etherton, chair of the American Heart Association’s nutrition committee, said: ‘In the United States avocados are not a mainstream food yet and they can be expensive, especially at certain times of the year.

‘Also, most people do not really know how to incorporate them in their diet except for making guacamole.

'But guacamole is typically eaten with corn chips, which are high in calories and sodium.

‘Avocados, however, can also be eaten with salads, vegetables, sandwiches, lean protein foods (like chicken or fish) or even whole.’

In the study 45 healthy, overweight or obese patients between the ages of 21 and 70 were put on three cholesterol-lowering diets.

For the study researchers used Hass avocados, the ones with bumpy green skin.

Participants consumed an average American diet (consisting of 34 per cent of calories from fat, 51 per cent carbohydrates, and 16 per cent protein) for two weeks prior to starting one of three cholesterol lowering diets.

They were assigned to a lower fat diet without avocado, moderate-fat diet without avocado, and moderate-fat diet with one avocado per day.

'Many people do not know how to incorporate avocados in their diet except for making guacamole and eating it with corn chips, which are high in calories and salt,' the researchers warned

The two moderate fat diets both provided 34 percent of calories as fat (17 per cent of calories from monounsaturated fatty acids/MUFAs), whereas the lower fat diet provided 24 per cent of calories as fat (11 per cent from MUFAs).

Each participant consumed each test diet for five weeks.

The researchers found that compared to the baseline average American diet, low-density lipoprotein (LDL) - the so called ‘bad cholesterol’ - was 13.5 mg/dL lower after eating the avocado diet.

In a patient with high LDL, this would be the equivalent of a 10 per cent fall.

LDL was also lower on the moderate fat diet without the avocado (8.3 mg/dL lower) and the lower fat diet (7.4 mg/dL lower), though the results were not as striking as the avocado diet.

Several additional blood measurements were also more favourable after the avocado diet including total cholesterol and triglycerides.

The findings are published in the Journal of the American Heart Association (must credit).

In addition to MUFAs, avocados also provided other beneficial compounds that could have contributed to the findings such as fibre and phytosterols.

The heart-healthy Mediterranean diet, includes fruits, vegetables, whole grains, fatty fish, and foods rich in monounsaturated fatty acids--like extra-virgin olive oil and nuts.

Dr Kris-Etherton, Distinguished Professor of Nutrition at Pennsylvania State University, in University Park, Pennsylvania, said: ‘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.’