Forty healthy men and women, with normal body weight. Volunteers consumed randomly 4 coffee beverages with 160 mg caffeine (hot instant coffee, cold instant coffee, cold espresso, hot filter coffee).

Forty healthy men and women, with normal body weight. Volunteers consumed randomly 4 coffee beverages with 160 mg caffeine (hot instant coffee, cold instant coffee, cold espresso, hot filter coffee).

Forty healthy men and women, with normal body weight. Volunteers consumed randomly 4 coffee beverages with 160 mg caffeine (hot instant coffee, cold instant coffee, cold espresso, hot filter coffee).

Forty healthy men and women, with normal body weight. Volunteers consumed randomly 4 coffee beverages with 160 mg caffeine (hot instant coffee, cold instant coffee, cold espresso, hot filter coffee).

Volunteers consumed cold espresso with 160 mg caffeine. Salivary gastrin, alpha-amylase and cortisol and self-reported GI symptoms and stress were collected at fasting and postprandially.

The volunteers visited the lab after an 8-hour fasting. Saliva samples were taken at fasting for the determination of fasting salivary gastrin. After the consumption of coffee, saliva samples were taken at 15, 30, 60' for the determination of gastrin. Saliva samples were collected by the method "Salivette". Saliva was carried out by chewing a swab for about 1 minute. Then, the swab was returned to the Salivette and the container was centrifuged and saliva sample was obtained. The samples were stored at - 20 degrees of Celsius. Gastrin was determined by an immunoenzymatic method. In order to record the effects of coffee consumption on gastrointestinal symptoms, the participants completed a visual analogue scale every time saliva samples were collected (time 0', 15', 30', 60', 120', 180'). The visual analogue scale (1 = not at all to 10 = very) included 12 questions about gastrointestinal symptoms.

The aim was to investigate if blood pressure, energy intake and physical activity changed during the intervention. Blood pressure was measured three times in a sitting position after 15 minutes of rest by a mercury sphygmomanometer at the beginning and ending of each trial respectively. There was a 2-minute interval between measurements. Then, the average blood pressure measurements were calculated. Dietary intake was analyzed by Diet Analysis Plus (version 6.1). The database was extensively modified to include new foods and recipes. Physical activity was estimated by using metabolic equivalents of different activities performed by the volunteers the previous 7 days. Then, mean daily energy expenditure was estimated.