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The effect of diterpenes cafestol and kahweol in lowering lipoprotein(a) is analyzed via four random trials. Healthy individuals instructed to drink strong, unfiltered coffee daily for two months yielded lower lp(a) levels compared to filtered coffee drinkers. Intake of coffee oil and purified mixtures of cafestol and kahweol also resulted in minimized lp(a) levels. This study, however, remains inconclusive and should never be taken as proof that drinking unfiltered coffee reduces cholesterol levels. The negative effects far outweigh the lp(a) reducing effects of these two lipids.

Background: A high plasma total homocysteine concentration is associated with increased risk of cardiovascular disease. Consumption of unfiltered or filtered coffee raises total homocysteine concentrations in healthy volunteers. The responsible compound, however, is unknown., Objective: The objective was to determine whether caffeine explains the homocysteine-raising effect of coffee., Design: Forty-eight subjects aged 19-65 y completed this randomized crossover study with 3 treatments, each lasting 2 wk. Subjects consumed 6 capsules providing 870 mg caffeine/d (test treatment), 0.9 L paper-filtered coffee providing approximately 870 mg caffeine/d, or 6 placebo capsules. Blood samples were drawn fasting and 4 h after consumption of 0.45 L coffee or 3 capsules., Results: The mean fasting plasma homocysteine concentration after the placebo treatment was 9.6 +/- 3.1 micro mol/L. The caffeine and coffee treatments increased fasting homocysteine by 0.4 micro mol/L (95% CI: 0.1, 0.7; P = 0.04), or 5%, and by 0.9 micro mol/L (95% CI: 0.6, 1.2; P = 0.0001), or 11%, respectively, compared with placebo. The increase in homocysteine concentrations 4 h after consumption of 0.45 L coffee relative to consumption of 3 placebo capsules was 19% (P = 0.0001). Caffeine treatment had a much weaker acute effect on homocysteine (4%; P = 0.09). Effects of caffeine were stronger in women than in men, but the effects of coffee did not differ significantly between men and women., Conclusions: Caffeine is partly responsible for the homocysteine-raising effect of coffee. Coffee, but not caffeine, affects homocysteine metabolism within hours after intake, although the effect is still substantial after an overnight fast.

Background: An elevated plasma concentration of total homocysteine is considered to be a strong risk factor for cardiovascular disease. Heavy coffee drinking has been related to high homocysteine concentrations in epidemiologic studies and in one experiment in which healthy subjects drank unfiltered, boiled coffee., Objective: Our goal was to determine whether daily consumption of paper-filtered coffee raises plasma concentrations of total homocysteine in healthy subjects., Design: Twenty-six volunteers (18-53 y of age) consumed 1 L/d of paper-filtered coffee brewed with 70 g regular ground beans or no coffee for 4 wk each in a randomized, crossover design., Results: The mean (+/-SD) plasma concentration of total homocysteine in fasting blood was 8.1 +/- 1.8 micromol/L after abstention from coffee and 9.6 +/- 2.9 micromol/L after 3-4 wk of coffee drinking, a difference of 1.5 micromol/L (95% CI: 0.9, 2.1 micromol/L) or 18% (P: < 0.001). Coffee increased homocysteine concentrations in 24 of 26 individuals. Circulating concentrations of vitamin B-6, vitamin B-12, and folate were unaffected., Conclusion: Drinking large quantities of paper-filtered coffee raises fasting plasma concentrations of total homocysteine in healthy individuals.

Moderate alcohol consumption is associated with a reduced risk of coronary heart disease. Part of this inverse association may be explained by its effects on HDL. Paraoxonase, an HDL-associated enzyme, has been suggested to protect against LDL oxidation. We examined the effects of moderate consumption of red wine, beer and spirits in comparison with mineral water on paraoxonase activity in serum. In this diet-controlled, randomised, cross-over study 11 healthy middle-aged men consumed each of the beverages with evening dinner for 3 weeks. At the end of each 3 week period, blood samples were collected pre- and postprandially and after an overnight fast. Fasting paraoxonase activity was higher after intake of wine (P<0. 001), beer (P<0.001), and spirits (P<0.001) than after water consumption (149.4+/-111.1, 152.6+/-113.1, 152.8+/-116.5 and 143. 1+/-107.9 U/l serum), but did not differ significantly between the 3 alcoholic beverages. Similar effects were observed pre- and postprandially. The increases in paraoxonase activity were strongly correlated with coincident increases in concentrations of HDL-C and apo A-I (r=0.60, P<0.05 and r=0.70, P<0.05). These data suggest that increased serum paraoxonase may be one of the biological mechanisms underlying the reduced coronary heart disease risk in moderate alcohol consumers

Unsaturated fatty acids with their double bond in trans configuration raise serum low-density lipoprotein (LDL) cholesterol and lipoprotein(a) levels, and lower high-density lipoprotein (HDL) cholesterol in humans when substituted for cis unsaturated fatty acids in the diet. These effects should increase the risk of coronary heart disease, which is confirmed by epidemiological studies. Trans fatty acids are formed from cis unsaturated fatty acids during hydrogenation of vegetable oils in food industries. Until recently, major dietary sources of trans fatty acids in the Netherlands were frying fats, shortenings, and margarines, which in the past contained up to 50% of trans fatty acids. Nowadays, most shortenings and margarines sold in the Netherlands have a low trans fatty acid content due to manufacturing changes in the recent past. However, frying fats used in fast-food outlets still contain over 30% of trans fatty acids. French fries sold in these outlets provide 7-8 g of trans fatty acids per portion. Producers of frying fats for fast-food outlets therefore should also reduce the trans fatty acid content of their products as much as possible.

Cafestol and kahweol-diterpenes present in unfiltered coffee-strongly raise serum VLDL and LDL cholesterol and slightly reduce HDL cholesterol in humans. The mechanism of action is unknown. We determined whether the coffee diterpenes may affect lipoprotein metabolism via effects on lipid transfer proteins and lecithin:cholesterol acyltransferase in a randomized, double-blind cross-over study with 10 healthy male volunteers. Either cafestol (61-64 mg/day) or a mixture of cafestol (60 mg/day) and kahweol (48-54 mg/day) was given for 28 days. Serum activity levels of cholesterylester transfer protein, phospholipid transfer protein and lecithin:cholesterol acyltransferase were measured using exogenous substrate assays. Relative to baseline values, cafestol raised the mean (+/- S.D.) activity of cholesterylester transfer protein by 18 +/- 12% and of phospholipid transfer protein by 21 +/- 14% (both P < 0.001). Relative to cafestol alone, kahweol had no significant additional effects Lecithin:cholesterol acyltransferase activity was reduced by 11 +/- 12% by cafestol plus kahweol (P = 0.02). It is concluded that the effects of coffee diterpenes on plasma lipoproteins may be connected with changes in serum activity levels of lipid transfer proteins.

Objective: To study the effects of prolonged intake of cafetière coffee, which is rich in the diterpenes cafestol and kahweol, on serum aminotransferase and lipid concentrations., Design: Randomised parallel controlled trial., Subjects: 46 healthy men and women aged 19 to 69., Intervention: Consumption of five to six strong cups (0.9 litres) a day of either cafetière (22 subjects) or filtered coffee (24 subjects) for 24 weeks., Main Outcome Measures: Mean changes in serum aminotransferase and lipid concentrations., Results: Cafetière coffee raised alanine aminotransferase concentration by up to 80% above baseline values relative to filtered coffee. After 24 weeks the rise was still 45% (9 U/l (95% confidence interval 3 to 15 U/l), P = 0.007). Alanine aminotransferase concentration exceeded the upper limit of normal in eight of the 22 subjects drinking cafetière coffee, being twice the upper limit of normal in three of them. Cafetière coffee raised low density lipoprotein cholesterol concentrations by 9-14%. After 24 weeks the rise was 0.26 mmol/l (0.04 to 0.47 mmol/l) (P = 0.03) relative to filtered coffee. Triglyceride concentrations initially rose by 26% with cafetière coffee but returned close to baseline values within six months. All increases were reversible after the intervention was stopped., Conclusions: Daily consumption of five to six cups of strong cafetière coffee affects the integrity of liver cells as suggested by small increases in serum alanine aminotransferase concentration. The effect does not subside with prolonged intake. High intakes of coffee brews rich in cafestol and kahweol may thus be responsible for unexplained increases in this enzyme activity in apparently healthy subjects. Cafetière coffee also raises low density lipoprotein cholesterol concentration and thus the risk of coronary heart disease.

Objective: To quantify the consumption of unfiltered coffee brews, which contain the cholesterol-raising diterpenes cafestol and kahweol, in elderly subjects., Design: Interviews of randomly selected elderly in the 1993 SENECA Study on Nutrition and the Elderly in Europe., Setting: Nine towns in eight European countries (Denmark, France, Italy, the Netherlands, Portugal, Switzerland, Poland, and Northern Ireland/United Kingdom)., Subjects: 962 relatively healthy elderly persons (460 men, 502 women) born between 1913 and 1918., Main Outcome Measure: Daily coffee consumption, classified by brewing technique., Results: About 90 percent of the examinees were daily coffee users in Roskilde/Denmark (population means; men 530 ml/d, women 425 ml/d) and Culemborg/the Netherlands (men 513 ml/d, women 285 ml/d), against only 12% in Marki/Poland (population means; men 14 ml/d, women 36 ml/d) and 7% in Coimbra/Portugal (men 8 ml/d, women 0 ml/d). Drip-filtered and instant coffee, which are poor in diterpenes, were the prevalent types in most survey towns. Espresso and mocha coffee, which contain intermediate amounts of diterpenes, were consumed daily by 31% of the coffee drinkers in Switzerland and by all coffee drinkers in Italy, but intake was too low to substantially affect serum cholesterol levels. Consumption of brews that are rich in diterpenes, such as cafetiere, boiled, or Turkish/Greek coffee, was negligible in all survey towns., Conclusions: Coffee drinking is common among elderly people in some European countries, but intake of cafestol and kahweol with unfiltered coffee brews is low.