High cholesterol results in a number of serious
complications like heart attack and stroke, making it imperative to control the
problem with medications. Drugs from the
statin group like simvastatin and rosuvastatin are often used to decrease the
"bad" cholesterol or LDL-cholesterol. These drugs decrease the production
of cholesterol by the body as well as increase its uptake by the liver, thus
reducing its blood levels.
Ezetimibe is a
comparatively newer drug that acts by decreasing absorption of cholesterol and
phytosterols by the intestines
. It is usually used along with statins for added
are similar to cholesterol but obtained from plant sources like nuts and
indicate that souble fibre in the intestines reduce the absorption of
Phytosterols from the diet and thus have a cholesterol-lowering effect. Other
studies however indicate that increase in absorption of phytosterols could have
the same detrimental effects on the body as cholesterol such as hardening of
Some studies indicate that the cholesterol-lowering
drugs belonging to the statin group, though very effective, can increase the
absorption of phytosterols in the intestine, leading to a mild to moderate
increase of phytosterols in the body. This could lead to an increase in
cardiovascular risk, though this view is still controversial.
have been shown to reduce blood cholesterol in prior studies
. They could be used along
with cholesterol lowering drugs- thus they may enhance the effect of the drugs
as well as allow the use of lower doses of the cholesterol-lowering drugs,
thereby reducing their side effects.
A study was
carried out to test the efficacy of dietary fiber in reducing cholesterol as
well as phytosterol levels in patients already taking effective
116 men and women between the ages of 30 and 75
years were included in the study. The participating individuals received the
cholesterol-lowering drugs rosuvastatin 40 mg or a combination of simvastatin
40 mg plus ezetimibe 10 mg, daily for 12 weeks. In addition, they were
randomized to receive or not 25 g of dietary fiber (corresponding to 6 g of
soluble fiber), divided into three daily doses administered before meals. They
were also encouraged to adopt lifestyle changes that help to reduce
Cholesterol levels were estimated at the start of
the trial and then 12 weeks into the trial. The researchers observed that significant cholesterol lowering was
obtained with anti-cholesterol medications irrespective of whether the patient
was on soluble fiber supplementation or not.
These included a decrease in
total cholesterol, LDL-cholesterol or bad cholesterol and triglycerides.
HDL-cholesterol or good cholesterol levels were unaffected.
researchers found that the level of the phytosterol campesterol was reduced in
patients administered dietary fibers.
This effect was especially seen when combined with
simvastatin and ezetimibe. Blood glucose
levels at week 12 were also lower in patients supplemented with fiber. The
researchers also found that fiber supplementation reduced weight in some
which is beneficial in patients suffering from high cholesterol.
This study indicates
that though dietary fiber does not have any effect on cholesterol levels that
are already controlled effectively by other medications, it does play a role in
. Thus, dietary fiber enhances the effect of ezetimibe in a safe way
without the use of additional medications.
The exact role
of phytosterols in the development of cardiovascular problems is currently
controversial. However, the findings of
this study may be relevant for certain people showing genetic variation in NPC1L1
or ABCG5/G8 genes.
This variation results in an increase the absorption of
sterols or decrease in sterol excretion into the intestinal lumen, thus resulting
in phytosterolemia. Further studies with larger number of patients are
warranted to establish this beneficial effect of dietary fibers.
1. The Role of Soluble Fiber Intake in Patients under Highly Effective
Lipid-lowering Therapy; Silvia Ramos et al; BMJ Nutrition 2011.