There is more evidence eating almonds is good for health, with US researchers finding they improve the function of 'good' cholesterol in the bloodstream.

Eating almonds helps the function of 'good cholesterol' in the body to improve overall heart health, according to a US study.

High-density lipoprotein (HDL) is known as the "good" cholesterol because it helps remove other forms of cholesterol from your bloodstream and arteries that have been linked to a greater risk of heart disease.

Researchers at Penn Sate university recently compared the levels of HDL cholesterol in people who ate almonds every day to those who ate a muffin instead.

The study, published in the Journal of Nutrition, found participants on the almond diet had improved HDL levels and functionality.

Professor of Nutrition Penny Kris-Etherton says the findings build on previous research on the effects of almonds on cholesterol-lowering diets.

"There's a lot of research out there that shows a diet that includes almonds lowers low-density lipoprotein or LDL cholesterol, which is a major risk factor for heart disease," Prof Kris-Etherton said.

"But not as much was known about how almonds affect HDL cholesterol, which is considered good cholesterol and helps lower your risk of heart disease."

The researchers wanted to see if almonds could not just increase the levels but also improve the function of HDL cholesterol.

In a controlled-feeding study, 48 men and women with elevated LDL cholesterol were assigned to two different six-week diets.

In both, their food intake was identical except for the daily snack. On the almond diet, participants received 43 grams - about a handful - of almonds a day. During the control period, they received a banana muffin instead.

The researchers found compared to the control diet, the almond diet increased a-1 HDL - more mature and larger HDL molecules - by 19 per cent.

HDL molecules grow in size as they clean up the 'bad' cholesterol from cells and tissue.

Additionally, the almond diet improved HDL function by 6.4 per cent, in participants of normal weight.

"We were able to show that there were more larger particles in response to consuming the almonds compared to not consuming almonds," Professor Kris-Etherton said.

"That would translate to the smaller particles doing what they're supposed to be doing. They're going to tissues and pulling out cholesterol, getting bigger and taking that cholesterol to the liver for removal from the body."

While almonds won't eliminate the risk of heart disease altogether they are a smart choice for a healthy snack, says Prof Kris-Etherton.

Almonds also provide a dose of good fats, vitamin E and fiber.

"If people incorporate almonds into their diet, they should expect multiple benefits, including ones that can improve heart health," Prof Kris-Etherton said.