Stress management offers strong potential for natural ingredients, particularly after the removal of herbal products like kava from many European markets.
Figures from the World Health Organisation show that 450 million people worldwide are affected by mental, neurological or behavioural problems at any given time.
US health authorities estimate that 19 million Americans suffer from anxiety disorders. And while consumers are increasingly looking for energy and wellbeing, they are also under more pressurised lifestyles and stress.
The new randomised, double-blind, crossover, placebo- controlled trial, led by researchers from the Catholic University of Korea, recruited 63 female volunteers with at least one stress-related disorder like anxiety, sleep problems and general fatigue.
The women were randomly assigned to receive either alphaS1-casein hydrolysate tablets (150 mg/day, Lactium, Ingredia) or placebo (Dietaroma) for 30 days. The participants then underwent a three-week washout period and then crossed over for a new 30-day period.
Stress-related symptoms were measured by self-reporting of the volunteers using a questionnaire that included 44 items quantify the severity of each stress-related disorder on a scale of one to ten. Measures were taken at day 0, 15 and 30 of each intervention period.
After 30 days of the casein hydrolysate supplements, symptoms of stress were significantly reduced, especially those related to digestion, cardiovascular, emotional, intellectual, and social problems, the researchers report in the European Journal of Clinical Nutrition.
"This study showed that a 30-day ingestion of alphaS1-casein hydrolysate decreased the stress-related symptoms in females suggesting that this product may be used as an effective functional ingredient alleviating such symptoms," concluded the researchers.
The study was funded by the French dairy ingredients company, Ingredia, and the Korea Ministry of Science and Technology.
The new results agree with previous clinical trials with healthy volunteers, which found 'a significantly greater positive evolution of stress symptoms' in five different areas.
Source: European Journal of Clinical Nutrition Advance online publication, doi: 10.1038/sj.ejcn.1602553 "Efficacy of alpha-casein hydrolysate on stress-related symptoms in women" Authors: J H Kim, D Desor, Y T Kim, W J Yoon, K S Kim, J S Jun, K H Pyun and I Shim