Postprandial plasma triglyceride and cholesterol responses to a low-fat meal.

Postprandial plasma cholesterol and triglyceride (TG) levels were measured after the consumption of a relatively low-fat (35% of calories) diet in 41 subjects. Plasma cholesterol levels did not change appreciably during the postprandial state. In 34 subjects a biphasic plasma TG response curve was noted, with an initial peak occurring 1 to 3 hr after feeding and a secondary TG peak 4 to 7 hr after the meal. The primary peak was greater than 90%, accounted for by chylomicrons, whereas the secondary peak represented very low-density lipoproteins (greater than 82%). Furthermore, the heights of the primary and secondary peaks were closely correlated to the fasting TG level (r = 0.61 and 0.72, respectively) indicating that the fasting TG concentration is an important determinant of the postprandial TG response. Because low-fat (high-carbohydrate) diets are known to raise fasting TG levels in patients who do not have fasting hyperchylomicronemia, and because relatively few patients have chylomicrons in the fasting state, these data suggest that such diets may lead to day long increases in plasma TG levels in the majority of subjects.