CClinicalTrials.gg
CompletedNCT03495336Updated Apr 12, 2018

The Effects of Unfiltered (Turkish) Coffee Consumption on Cardiovascular Risk Parameters

An interventional study of coffee abstention phase and LR Coffee consumption in Cardiovascular Diseases, sponsored by Eastern Mediterranean University. Completed at 1 site in Cyprus. Open to participants aged 20 Years to 35 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2018-04-12.

Sponsored by Eastern Mediterranean University · Not applicable, Interventional, and Other

Phase
Not applicable
Study type
Interventional
Enrollment
28
Allocation
Randomized
Ages
20 Years to 35 Years
Sex
All
01

Study summary

Purpose/Objective: The aim of this study is to investigate the impact of boiled unfiltered (Turkish) coffee consumption on the plasma cardiovascular risk parameters of healthy subjects. The study also explores whether two unfiltered boiled (Turkish) coffee beverages that differ in content due to different roasting degrees will differentially affect cardiovascular biomarkers.

Methods: In this crossover intervention study, healthy, nonsmoking, habitual Turkish coffee drinkers (n=28) were randomized to consume at least 3 cups of Light (LR) or Dark (DR) roast Turkish coffee brews per day for 4 weeks after a washout period (WO) of 2 weeks. Subsequent to each coffee abstinence period, both groups received the alternative intervention. After the first WO and the coffee intervention periods, anthropometric measures, blood pressure, heart rate and 13 biochemical parameters were collected and dietary records were completed.

Read the detailed description

Background: Considerable controversy exists regarding the link between coffee consumption and cardiovascular disease (CVD) risk. It has been shown that different coffee preparation and brewing methods influence the concentration of compounds present in the final coffee brew. Unlike coffee traditionally consumed in the western world, Turkish coffee is not drip filtered, but rather its method of preparation involves slowly boiling water that is mixed with thinly ground coffee beans. This style of preparation results in a greater amount of biologically active components (caffeine and diterpenes) remaining in the liquid. In addition to preparation styles, roasting process greatly affects the chemical composition of the coffee. Coffee types differing in content of major constituents differ with regard to cardiovascular health effects.

Purpose/Objective: The aim of this study is to investigate the impact of boiled unfiltered (Turkish) coffee consumption on the plasma cardiovascular risk parameters of healthy subjects. The study also explores whether two unfiltered boiled (Turkish) coffee beverages that differ in content due to different roasting degrees will differentially affect cardiovascular biomarkers.

Methods: In this crossover intervention study, healthy, nonsmoking, habitual Turkish coffee drinkers (n=28) were randomized to consume at least 3 cups of Light (LR) or Dark (DR) roast Turkish coffee brews per day for 4 weeks after a washout period (WO) of 2 weeks. Subsequent to each coffee abstinence period, both groups received the alternative intervention. After the first WO and the coffee intervention periods, anthropometric measures, blood pressure, heart rate and 13 biochemical parameters were collected and dietary records were completed.

02

Conditions studied

  • Cardiovascular Diseases

Keywords

  • Boiled coffee
  • Cardiovascular disease
  • Cholesterol
  • Homocysteine
  • Turkish coffee
  • Diterpenes
  • Unfiltered coffee
03

Who can participate

Ages eligible
20 Years to 35 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Regular Turkish coffee consumer ≥ 1 cups/day
  • Body mass index (BMI) 18.5-24.9 kg/m2 )
  • Non-smoker or former smoker (more than a year)
  • Willingness to abstain from coffee drinking
  • Willingness to consume ≥ 3 cups/day of Turkish coffee

Exclusion criteria

Exclusion Criteria:

  • Acute or chronic diseases
  • Severe illness with in-patient treatment during last 3 months
  • Use of regular medication or any supplements
  • Weight reduction ˃2 kg/week during the last month
  • Pregnancy or breastfeeding
  • Regular strong physical activity with ≥1h/day
  • High alcohol intake a weekly intake of ˃7 units for women and ˃14units for men
  • Excess consumption of total fat ˃35% of daily calories
  • Consumption of saturated fatty acid ˃10% of daily calories
  • Cholesterol intake ˃300mg/day
04

Study design

Phase
Not applicable
Primary purpose
Other
Allocation
Randomized
Intervention model
Crossover assignment
Masking
None (open label)
Enrollment
28 participants (actual)

Study arms

  • Experimental
    Washout period

    Coffee abstention phase for 2 weeks.

    Other: coffee abstention phase

  • Experimental
    Light roast coffee (LR)

    Participants will follow LR Coffee consumption procedure and consume at least 3 cups of Light (LR) roast Turkish coffee brews per day for 4 weeks after a washout period (WO) of 2 weeks.

    Other: LR Coffee consumption

  • Experimental
    Second washout period

    coffee abstention phase for 2 weeks

    Other: coffee abstention phase

  • Experimental
    Dark roast coffee (DR)

    Participants will follow DR Coffee consumption procedure and consume at least 3 cups of Dark (DR) roast Turkish coffee brews per day for 4 weeks after a washout period (WO) of 2 weeks.

    Other: DR Coffee consumption

Interventions

  • Othercoffee abstention phase

    no coffee consumption for 2 weeks

  • OtherLR Coffee consumption

    for 4 weeks participants consumed only LR Turkish coffee

  • OtherDR Coffee consumption

    for 4 weeks participants consumed only DR Turkish coffee

05

What researchers measure

Primary outcomes

  1. Comparing the serum lipid levels of all interventions

    Differences in concentration of serum lipid levels of participants in coffee-free period (washout) and after LR or DR coffee ingestion were measured. Blood samples were obtained at the end of two weeks washout period and after each four weeks coffee intervention period, and sera were stored at -30∘ C, until analytical measurements were performed. The levels of serum lipids: Triglycerides (mg/dL), Total cholesterol (mg/dL), and HDL cholesterol (mg/dL) were determined using a Dimension Xpand Plus integrated clinical chemistry autoanalyzer (Siemens Healthcare Diagnostics, Deerfield, IL, USA). The serum levels of LDL cholesterol (mg/dL) were calculated using Friedewald's equation. Differences in blood lipid variables were analyzed by repeated-measures ANOVA for comparisons of LR coffee intake with DR and of each roast with the washout.analyses were performed using SPSS 24.0 (IBM-SPSS Inc., Chicago, IL, USA).

    Time frame: 12 weeks

Secondary outcomes

  1. Comparing the weight (kg) of all interventions

    Weight was measured after the washout period and after each intervention. Weight (in kilograms) was measured in light clothing, without shoes.

    Time frame: 12 weeks

  2. Comparing the height (cm) of all interventions

    after the washout period and after each intervention height was measured using a stadiometer to the nearest centimeter.

    Time frame: 12 weeks

  3. Comparing the body mass index (BMI) of all interventions

    BMI was calculated (weight/height squared; in kilograms per square meter)

    Time frame: 12 weeks

  4. Comparing the body fat percentage (%) of all interventions

    after the washout period and after each intervention the percentage of body fat and fat free mass (FFM) was measured by Tanita Segmental Body Composition Analyzer BC-418 MA (Tanita Corp. Tokyo, Japan)

    Time frame: 12 weeks

  5. Comparing the waist circumference (cm) of all interventions

    after the washout period and after each intervention waist circumferences (midway between the rib cage and the iliac crest) were measured using a flexible tape.

    Time frame: 12 weeks

  6. Comparing the blood pressure (BP) (Systolic and Diastolic blood pressure (mmHg)) of all interventions

    after the washout period and after each intervention BP and heart rate (beats/min) was monitored using an automatic arm sphygmomanometer (Pic Indolor Diagnostic, BS 150, Artsana, Italy) after a 5-min rest in a sitting position.

    Time frame: 12 weeks

  7. Comparing the 3-day food diaries (1 weekend day and 2 weekdays) taken during each intervention

    Daily nutrient intake was calculated by using computer software (Ebispro, Stuttgart, Germany; Turkish version: BeBiS, Vers. 6.1)

    Time frame: 12 weeks

  8. Comparing the physical activity levels of each intervention

    The validated Turkish version of the International Physical Activity Questionnaire (IPAQ)-short form (7 item) was administered. The IPAQ questionnaires list activities and request estimates of durations and frequencies for each activity engaged in over the past week. Durations are multiplied by known METs per activity and the results for all items are summed for the overall physical activity score. Scores for walking and for moderate and vigorous activities are sums of corresponding item scores. A sitting question is not included in physical activity score. Physical activity level (PAL): Extremely inactive \<1.40 , Sedentary 1.40-1.69, Moderately active 1.70-1.99, Vigorously active 2.00-2.40,Extremely active\>2.40

    Time frame: 12 weeks

  9. Comparing the Homocysteine levels of all interventions

    Differences in concentration of homocysteine (μmol/L) levels of participants after 2wk coffee-free period (washout) and after 4 weeks of LR or DR coffee ingestion was compared. EDTA-treated blood samples for total homocysteine (μmol/L) analysis were immediately refrigerated (placed on ice) until the plasma was separated by centrifugation. All the samples were assayed for Homocysteine by using High Performance Liquid Chromatography with fluorescent detection technique (HPLC-FLD). Differences in homocysteine variables were analyzed by repeated-measures ANOVA for comparisons of LR coffee intake with DR and of each roast with the washout.analyses were performed using SPSS 24.0 (IBM-SPSS Inc., Chicago, IL, USA).

    Time frame: 12 weeks

  10. Comparing the fasting blood glucose levels of all interventions

    Concentration of fasting blood glucose levels in coffee-free period (washout) and changes after LR or DR coffee ingestion were compared.Blood samples were obtained at the end of two weeks washout period and after each four weeks coffee intervention period, and sera were stored at -30∘ C, until analytical measurements were performed. The levels of Fasting blood glucose (mg/dL), were determined using a Dimension Xpand Plus integrated clinical chemistry autoanalyzer (Siemens Healthcare Diagnostics, Deerfield, IL, USA). Differences in human variables were analyzed by repeated-measures ANOVA for comparisons of LR coffee intake with DR and of each roast with the washout.

    Time frame: 12 weeks

  11. Comparing the serum Malondialdehyde levels of all interventions

    Concentration of Serum Malondialdehyde (μM) levels at the end of coffee-free period (washout) and changes after LR or DR coffee ingestion were compared.Serum Malondialdehyde (μM) levels were determined with a colorimetric assay kit (Cayman Chemical, Ann Arbor, MI). Differences in human variables were analyzed by repeated-measures ANOVA for comparisons of LR coffee intake with DR and of each roast with the washout.

    Time frame: 12 weeks

Other outcomes

  1. Analysis of the content of the diterpenes (cafestol and kahweol) (mg/55mL) in LR and DR Turkish coffee brews

    Cafestol and kahweol were analyzed in the unsaponified matter by HPLC-DAD. Diterpenes content of the two coffee beverages were reported as mean±standard deviation and Kruskal-Wallis test was used for statistical comparison of coffee roasts.. All analyses were performed using SPSS 24.0 (IBM-SPSS Inc., Chicago, IL, USA).

    Time frame: 3 months

  2. Analysis of the content of the caffeine (mg/mL) in LR and DR Turkish coffee brews

    Caffeine was determined by high-performance liquid chromatography (HPLC, Aligent Technologies, USA) with diode-array detector (DAD) and mass spectrometer. content of the two coffee beverages were reported as mean±standard deviation and Kruskal-Wallis test was used for statistical comparison of coffee roasts.. All analyses were performed using SPSS 24.0 (IBM-SPSS Inc., Chicago, IL, USA).

    Time frame: 3 months

06

Study locations

1 site
  • Eastern Mediterrenean University
    Famagusta, 99450, Cyprus
07

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

08

Registry details

Key details

Study ID
NCT03495336
Lead sponsor
Eastern Mediterranean University
Responsible party
Fatma Hülyam Eren (Instructor, Eastern Mediterranean University) — Principal investigator
First posted
Apr 12, 2018
Start date
Mar 22, 2017
Primary completion
Jun 22, 2017
Completion
Oct 22, 2017
Last update
Apr 12, 2018

Study contacts

Tanju Besler, Prof.
study chair · Eastern Mediterranean University

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Apr 2018. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion