The aim of our investigation was the assessment of the influence of natural coffee and that modified by water and pressure extraction (60% less of 2-methyl isoborneol) on the level of homocysteine, folic acid and vitamin B6 in healthy volunteers.
Material and methods: The study was conducted on 36 healthy volunteers. 20 women and 16 men; smokers constituted half of the group. The study was conducted as a double blind trial (coffee without labels) after randomization into two groups. Initially for 4 weeks, one group drank natural coffee and the other a modified one. After four weeks there was a 28-day break in drinking coffee, after which the groups swapped roles and another trial lasted for the subsequent 4 weeks. All people examined drank three servings of coffee a day brewed from 13 g of material in 180 ml of boiling water. Throughout the entire experiment the examined subjects did not change their diets and did not take any vitamin supplements. Blood for analysis was drawn four times and the following analyses were carried out. homocysteine, folic acid, vitamin B6 total, LDL and HDL-cholesterol, triglicerides, Lp(a) and fibrinogen.
Results: We found a significant increase level of plasma homocysteine from 9.6 to 11.4 micromol/l (p < 0.001) in persons drinking natural, unfiltered coffee. However drinking modified coffee free from irritants resulted in a tendency towards lowering the level of homocysteine (from 9.1 to 8.7 micromol/l).
Conclusions: From the above study it may be concluded that lowering the content of irritants in coffee results in reducing its undesired influence on the homocysteine level. Reduction of natural coffee consumption or its change on coffee with lowering the content of irritants should be recommended to cardiovascular disease persons.