Studies related to and

Genetic Determinants Of Blood Pressure Responses To Caffeine Drinking

Effect Increase
Trial Design Double blind
Trial Length n/a
Number of Subjects 110
Gender n/a
Notes for this study:
After ingestion of 3mg/kg bodyweight caffeine, systolic and diastolic blood pressure increased by 4+/-12mmHg and 3+/-10mmHg respectively.

2 polymorphisms of adenosine receptors, ADRA2B I and ADORA2A TT, were highly associated with the increases in blood pressure.

Effects Of Caffeinated And Decaffeinated Coffee On Biological Risk Factors For Type 2 Diabetes: A Randomized Controlled Trial

Effect None
Trial Design Double blind
Trial Length 1-6 months
Number of Subjects 45
Gender Both Genders
Age Range 30-44, 45-64
Body Types Obese, Overweight
Notes for this study:
In 45 nearly obese persons (habitual coffee drinkers) with the average age of 40, consumption of 5 cups of caffeinated coffee was associated with increased adiponectin concentrations relative to control but not to decaffeinated coffee (likely indicative of another bioactive).

Effects on insulin sensitivity and blood glucose did not differ caffeinated and decaffeinated coffee, although decaffeinated coffee was associated with a significant drop in diastolic blood pressure relative to control and caffeinated.

Dose Response Effects Of A Caffeine-containing Energy Drink On Muscle Performance: A Repeated Measures Design

Effect Increase
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 12
Gender Both Genders
Age Range 18-29, 30-44
Body Types Trained, Average
Notes for this study:
In 12 active and healthy participants (light caffeine consumers at less than 60mg daily), an intake of a caffeinated energy drink (compared to placebo, the same energy drink but not caffeinated) was able to increased blood pressure and heart rate at rest without significantl affecting metabolic rate up to 3mg/kg bodyweight.

Power output, as measured by half-squat and bench, was increased only at 3mg/kg bodyweight with no significant influence at 1mg/kg.

Effects Of 1,3-dimethylamylamine And Caffeine Alone Or In Combination On Heart Rate And Blood Pressure In Healthy Men And Women

Effect Increase
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 10
Gender Both Genders
Age Range 18-29
Body Types Average
Notes for this study:
Caffeine, at 250mg, was able to increase blood pressure in a sample of otherwise healthy young persons. The increase was smaller in magnitude than the combination of caffeine and 1,3-DMAA, which was a notable increase in blood pressure.

Subjective, Behavioral, And Physiological Effects Of Acute Caffeine In Light, Nondependent Caffeine Users

Effect Increase
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 102
Gender Both Genders
Age Range 18-29, 30-44, 45-64
Body Types Overweight, Average
Notes for this study:
102 light, nondependent caffeine users were subject to varying doses of caffeine and tested for its psychostimulatory responses.

Sedation was significantly lowered and stimulation was higher, although still lesser to 20mg d-amphetamine (used as comparison) even when at 450mg caffeine. No significant interactions on euphoria or desire of 'more drug' were noted with caffeine, but were with d-amphetamine.

Performance on working memory was decreased at the 450mg dosage but processing speed at all doses was increased, most significantly at the 450mg dosage.

Caffeine: A Double-blind, Placebo-controlled Study Of Its Thermogenic, Metabolic, And Cardiovascular Effects In Healthy Volunteers

Effect Increase
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 6
Gender Both Genders
Age Range 18-29, 30-44
Body Types Untrained, Overweight, Average
Notes for this study:
In low habitual coffee drinkers (150-300mL daily), supplementation of 100-400mg caffeine increased the metabolic rate (9.2+?-5.7, 7.2+/-6.0, and 32.4+/-8.2kcal/h increase) with the highest dose also increasing plasma glycerol (indicative of fat burning) and lactate. Blood pressure was increased at 400mg only in supine position.