Pasta that's been enriched with a type of fiber called beta-glucan encourages the growth of "good" bacteria in your gastrointestinal tract that could boost your immune system and help fight diabetes and high cholesterol, among other health benefits.

For two months, scientists observed participants who ate the pasta for two months to find that they had increased populations of healthy bacteria and reduced colonies of the non-beneficial kind.

Subjects' low-density lipoprotein (LDL) cholesterol -- otherwise known as the "bad" kind -- was reduced, according to the paper on the project that's part of a broad effort to explore prebiotic foods.

Beta-glucans are sugars found in oats, barley, bran, baker's yeast and some mushrooms and are often used as texturing agents in food processing and medically to ward off diabetes, cancer, high cholesterol and to boost immunity.

The human gut itself cannot digest them, but rather certain species of the gut's bacteria digest them, say the researchers.

Working with fecal and blood samples from before and after the experiment, the research team observed a significant increase in the health-giving Lactobacilli species and a reduction in non-beneficial bacteria such as Enterobacteriaceae.

They also observed an increase in short chain fatty acids and a string of other compounds linked to anti-inflammatory activity, according to the paper.

Blood samples indicated that LDL cholesterol had fallen from 107.4 to 93.8 mg/dl, on average.

The special pasta is a mix of 75 per cent durum wheat flour and 25 per cent whole grain barley flour, according to the paper.

Subjects ate 100 grams per day, which provided them with the three-gram-recommended daily dose of barley beta-glucans by both US and European standards.

Developed around 7000 BC in Central Europe, durum wheat is a widely cultivated crop today that's commonly used in pasta, recognized for its high protein content.

Whole grain barely flour has been spared the process of refinement thought to take away essential nutrients and barley itself has been associated with improved blood sugar, glucose levels and lower glycemic index.

"These results highlight the influence of fibers and of the Mediterranean diet on gut microbiota, and indirectly on human health," says co-author Maria De Angelis of the University of Bari Adlo Moro in Italy.

The paper was published in the journal Applied and Environmental Microbiology.