Some doctors think there is not enough evidence that low cholesterol levels are harmful.
Ask the doctor: Is my LDL cholesterol too low? (Harvard.edu, 2012)
There really isn't evidence of harm from driving your LDL too low. In
the past, some scientists worried that extremely low LDL levels could
result in blood vessel ruptures and perhaps increase the risk of
getting certain types of cancer. Those concerns have faded after
neither occurred in large clinical trials that involved reducing
people's LDL to very low levels.
Still, taking larger doses of atorvastatin...increases the risk of
statin side effects, which include muscle and liver damage. For that
reason, moving to a lower dose is a good idea.
Can your total cholesterol level be too low? (Mayo Clinic)
Although the risks are rare, very low levels of LDL cholesterol may be
associated with an increased risk of:
- Hemorrhagic stroke
- Preterm birth and low birth weight if your cholesterol is low while you're pregnant
The potential risk of lowering LDL cholesterol to very low levels has
not been confirmed, and its association with certain health risks is
still under debate.
Still, according to some studies, there might be some risks of too low cholesterol levels (usually caused by taking statins).
Low Cholesterol is Associated with Mortality from Cardiovascular Diseases: A Dynamic Cohort Study in Korean Adults (PubMed)
Groups with the lowest group having TC < 160 mg/dL as well as the
highest group having >= 240 mg/dL were associated with higher
cardiovascular disease mortality...Based on the results of this study,
caution should be taken in prescribing statins for primary prevention
among people at low cardiovascular risk in Korean adults.
Low cholesterol as a risk factor for primary intracerebral hemorrhage: A case–control study (PubMed, 2012)
This study confirms an increased risk of primary intracerebral
hemorrhage associated with low cholesterol both in men and women,
especially in older individuals.
One who has very low cholesterol levels can discuss with a doctor about adjusting the dose or statins or even stopping them.