A study that was published in Biological Psychology (epublished ahead of print October 1, 2011) looked at the effect omega-3 fatty acid supplementation had on stress. The 34 subjects of the study received either 1.4 grams of EPA and DHA or a placebo for 21 days. Cardiovascular measurements were obtained in the laboratory during baseline and during a standard mental arithmetic task, where participants were instructed to engage in serial subtractions by 17s from a four-digit number and cardiovascular reactivity to the task was calculated. Mean arterial pressure reactivity was reduced in the group receiving the supplements, but not in the placebo group.