Researchers say fermented milk developed from a bacteria called Lactococcus lactis strain H61 improved skin health among young women.
The research team, led by Hiromi Kimoto-Nira, PhD, of the National Agriculture and Food Research Organization (NARO) Institute of Livestock and Grassland Science (NILGS) in Japan, publish their findings in the Journal of Dairy Science.
Past research has indicated that probiotics - defined as live microorganisms, or bacteria, which offer health benefits - may be useful in treating skin diseases. A 2013 study reported by Medical News Today, for example, found that a probiotic called Bifidobacterium infantis 35624 may be effective against psoriasis - an autoimmune disease that causes a red, scaly rash.
Kimoto-Nira notes, however, that very few studies have assessed the effects of probiotics on the skin of healthy individuals.
As such, the researchers set out to determine the skin benefits of fermented milk created using a bacteria called Lactococcus lactis strain H61, which has been widely used in the production of fermented dairy products in Japan over the past 50 years.
The team enrolled 23 women aged 19-21. The women were randomized to consume either H61-fermented milk or conventional yoghurt once a day for 4 weeks.
The study was double-blind, meaning both the participants and the researchers were unaware of which product each subject was consuming.
Blood samples were taken from the participants at the beginning and end of the study. By assessing the participants' cheeks and inner forearms, the researchers measured skin hydration, melanin levels and elasticity, while sebum content (oil secreted by the sebaceous gland) was measured through assessment of subjects' cheeks only.
Although skin hydration levels had increased among both groups of participants by the end of the study, the team found that those who had consumed the H61-fermented milk had significantly higher sebum levels, indicating better skin protection.
Commenting on the findings, the researchers say:
"As skin lipids contribute to maintaining the skin barrier, H61-fermented milk would provide beneficial effects on skin for young women."
The team notes that no other skin differences were found between the two groups.
Probiotics are most commonly associated with promoting better intestinal function and digestion, but as shown in this study, their benefits may reach further.
Earlier this year, Medical News Today reported on a study claiming that regular consumption of probiotics could help lower blood pressure, while a more recent study found that a yoghurt containing the bacteria Lactobacillus rhamnosus may protect children and pregnant women against heavy metal poisoning.