Reduction of serum cholesterol and low-density lipoprotein cholesterol levels in a juvenile population after isocaloric substitution of whole milk with a milk preparation (skimmed milk enriched with oleic acid)

Abstract

Objective: To study the effects of serum lipid levels by isocaloric substitution of whole milk intake in a group of children with a milk preparation (fat-free milk enriched with oleic acid containing a small amount of cholesterol) that is frequently consumed in our community. Design: A crossover clinical trial was carried out with random selection. There were 88 children of both sexes, ranging in age from 3 to 9 years, selected at a Primary Care Center. The children were divided into two homogeneous groups. The first group consumed whole milk for the first 7-month study period, whereas the second group drank the milk substitute. At the end of the first test period, serum lipid levels were measured. Then the type of diet was reversed: Group 1 children consumed the milk substitute whereas Group 2 children drank whole milk. The rest of their intake did not vary throughout the study. At the end of the second 7-month period we measured serum lipid levels again. The levels of serum lipid evaluated were total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, Apoprotein A1, Apoprotein B, and lipoprotein (a). For the statistical analysis the nonpaired and paired t tests were used. Results: The mean level of cholesterol after taking whole milk was 4.53 mmol/L (175.26 mg/dl), and the mean level after taking the milk preparation was 4.2 mmol/L (162.65 mg/dl), which indicates a 7.2% decrease. The mean level of low- density lipoprotein cholesterol after whole milk intake was 2.73 mmol/L (106.1 mg/dl), whereas after consuming the milk preparation it was 2.47 mmol/L (96.1 mg/dl), which indicates a decrease of 9.5%. Triglycerides were reduced from 0.83 mmol/L (73.53 mg/dl) after whole milk to 0.72 mmol/L (63.79 mg/dl) after the milk substitute, which suggests a 13.25% decrease. High- density lipoprotein cholesterol, apoprotein A1, apoprotein B, and lipoprotein (a) did not undergo any significant change. Conclusions: To reduce serum levels of total cholesterol and low-density lipoprotein cholesterol, without reducing caloric intake, it may be beneficial to substitute the whole milk customarily consumed by children with a milk preparation of fat-free milk enriched with oleic acid.