Dr. Illingworth et al., ROLE OF DIETARY-CHOLESTEROL IN THE OPTIMAL DIET FOR THE TREATMENT OF HYPERCHOLESTEROLEMIA, Canadian journal of cardiology, 11, 1995, pp. 115-117
OBJECTIVE: This paper discusses studies in which the effects of dietar
y cholesterol on the plasma concentrations of lipids and lipoproteins
have been evaluated in adult human subjects including patients with hy
po- and hypercholesterolemia. DESIGN: The dietary studies were conduct
ed on an outpatient basis in the Clinical Research Center. Each dietar
y period was four weeks in duration and an adequate washout period was
interposed between each dietary phase. SETTING: A university medical
centre. PATIENTS: The participants in these studies were adult men or
women with hypocholesterolemia, normal volunteers or patients with pri
mary hypercholesterolemia. INTERVENTIONS: The dietary periods consiste
d of three separate dietary phases in which dietary cholesterol was a
single variable. The diets contained 50 mg/day of cholesterol for the
low cholesterol diet, 350 mg/day for the moderate cholesterol diet and
650 mg/day for the high cholesterol diet. RESULTS: Concentrations of
total and low density lipoprotein (LDL) cholesterol increased in all t
hree patient groups from the low cholesterol to the moderate cholester
ol to the high cholesterol diet but the magnitude of increase in LDL c
holesterol concentrations was greater in the patients with pre-existen
t hypercholesterolemia and least in the patients with hypocholesterole
mia. in all three patient groups an increased intake of dietary choles
terol was-associated with suppression of endogenous cholesterol biosyn
thesis as assessed by the urinary excretion of mevalonic acid. CONCLUS
IONS: An increased intake of dietary cholesterol results in increases
in the plasma concentrations of total and LDL cholesterol in patients
with inherently low, normal or high concentrations of LDL cholesterol
but the magnitude of increase is greatest in those patients with pre-e
xistent hypercholesterolemia. These results support: the view that res
triction of dietary cholesterol leads to a reduction in the plasma con
centrations of total and LDL cholesterol and is an appropriate recomme
ndation for patients with known hypercholesterolemia or patients in wh
om medical recommendations call for a reduction. in the plasma concent
rations of total and LDL cholesterol.