Serum lipids, apoproteins and nutrient intake in rural Cretan boys consuming high-olive-oil diets.

A high intake of olive oil has produced high levels of high-density and low levels of low-density lipoprotein cholesterol in short-term dietary trials. To investigate long-term effects of olive oil we have studied the diet and serum lipids of boys in Crete, where a high olive oil consumption is the norm. Seventy-six healthy rural Cretan boys aged 7-9 years were studied. The diet was assessed by a 2-day dietary recall. Blood was collected according to a standardized protocol and sera were analyzed in a rigidly standardized laboratory. The mean daily intake of energy was 11.0 MJ (2629 kcal). The intake of fat (45.0% of energy) and oleic acid (27.2% of energy) was high, and that of saturated fat low (10.0% of energy), reflecting a high consumption of olive oil. The high consumption of olive oil was confirmed by a high proportion of oleic-acid (27.1%) in serum cholesteryl fatty acids. Mean concentration of serum total cholesterol was 4.42 mmol l-1 (171 mg dl-1), of HDL-cholesterol 1.40 mmol l-1 (54 mg dl-1), of serum triglycerides 0.59 mmol l-1 (52 mg dl-1), of apo-AI 1210 mg l-1 and of LDL apo-B 798 mg l-1. The body mass index of the Cretan boys (18.2 kg m-2) was on average 2 kg m-2 higher than that of boys from other countries. Contrary to our expectation, the Cretan boys did not show a more favourable serum lipoprotein pattern than boys from more westernized countries studied previously using the same protocol. Our hypothesis that a typical, olive-oil-rich Cretan diet causes a relatively high HDL- to total cholesterol ratio is not supported by the present findings.