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Medical Cholesterol- how low is too low?

  1. Feb 8, 2009 #1
    Almost all the information I find online about cholesterol is that one should ideally have a cholesterol level below 200. However, I have also read articles claiming that low cholesterol can also become a health risk. What these articles lack are solid numbers- what is the normal, healthy range of cholesterol? What numbers should one avoid falling under? Wikipedia tells me that any cholesterol lower than 160 is considered to fall under the category of hypocholesterolemia. Does anyone know if this is accurate?

    My cholesterol levels have been checked twice (to my knowledge) both times in the past six months when I donated blood. The first reading put my total cholesterol at 115, the second put it at 117. Now, I know that such low levels are considerably below what is typical, but is it low enough to be a serious health concern?

    *Yes, I have read the disclaimer. Yes, I intend to bring it up with a licensed medical doctor at my next check-up. I'm just wondering if anyone happens to have any useful information on what level of cholesterol is considered to be too low.
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  3. Feb 9, 2009 #2

    jim mcnamara

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    http://www.circ.ahajournals.org/cgi/content/full/92/9/2365 [Broken]

    Here is a bit of research from the American Heart Association on the subject. Very limited data, so this limits conclusions as well.
    Last edited by a moderator: May 4, 2017
  4. Feb 9, 2009 #3

    Andy Resnick

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    I only know two things about cholesterol- 1) it's an important structural modifier of membrane rigidity (cholesterol increases the rigidity), and 2) we synthesize cholesterol in the liver in addition ot dietary intake.

    A quick PubMed search on Hypocholesterolemia turned up 37 review articles, but nothing obviously significant other than a report on embryo development.
  5. Feb 9, 2009 #4


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    Indeed I can't readily find information on the pathophysiology of hypocholesterolemia. If you are in an otherwise healthy condition and you maintain a varied diet (which I assume when you are donating blood), I would not worry about it.

    I saw an article about familial hypobetalipoproteinemia (FHBL), which is characterized by hypocholesterolemia due to a mutation in the APOB gene. The mutation acts semi-dominant, causing lowered cholesterol levels in heterozygous individuals (and extremely low levels in homozygous individuals). The mutation was said to be non-symptomatic in heterozygous individuals http://www.clinchem.org/cgi/reprint/50/10/1725, it would be beneficial to have lowered LDL levels.
  6. Feb 9, 2009 #5
    Oddly enough, it does not seem to be a familial thing. My father struggles with high cholesterol, and my family history in general would probably tend to be biased towards abnormally high cholesterol rather than low. But yes, I am in generally good health aside from my rather sedentary lifestyle, so I'm not going to panic and consider this to be anything urgent.
  7. Jun 25, 2009 #6
    The one time I checked my overall cholesterol, it was 80. I went to see my doctor, and he checked for diseases like cancer and tumor and found nothing. I'm in good to fanstastic health in every other conceivable way, and the doctor doesn't seem to be concerned. My LDL to HDL ratio was very good. My overall cholesterol is just low. I like eating eggs and meat and fast food as much as any other american.

    For me the condition is hereditary. My father has always tested below 90, and we don't know the lowest because he often tests lower than the doctor's instrument can measure (which I think is 75 and below). He has high blood sugar (which would become diabetes if he didn't watch his diet so carefully) and is otherwise healthy. His father before him also had very low cholesterol and died of liver failure in his early 70's, without diabetes. My dad's brother is dying of liver failure in his early 60's (though both he and my grandpa abused themselves health-wise). Since cholesterol is produced in the liver, I figure there may be a connection. My brother, on the other hand, has cholesterol above 200.

    Anyway, if freakishly low cholesterol does kill my family, it doesn't do it until late, and perhaps not at all if we take care of our livers. I was denied the premium rate on life insurance for my cholesterol alone, which kind of ticked me off, but I seriously doubt it will kill me any time soon, if at all.

    -Clint Kimball
  8. Jul 7, 2009 #7
    Thanks for that link. It cleared my confusion on the readings. I had a test a few years ago and the result was 5.7, on the high side of normal. My doctor put me on statins. After five days I was so sick and miserable I never touched another. Was about a week before I felt normal again. I am over 70 and in excellent health.
    Last edited by a moderator: May 4, 2017
  9. Aug 10, 2009 #8
    Once 15 years ago I was rushed to the hospital because I felt pain in my heart, and when they measured my blood the only thing they could find was that my cholesterol was unmeasurable they called it "below critical".
    I don't know if it was the cause of my feeling bad, but if it was, it feels awful.
  10. Aug 22, 2009 #9
    Just happened across this forum --

    I used to be very, very, very active, and about 2 years ago I started to feel worse and worse, until now, I barely have energy to get up... I went in for a physical about a year ago to make sure that everything was okay and they found that I had very low Cholesterol levels: in the mid-high 90s (don't remember exactly)

    Just went in for another physical a year later and found that my cholesterol levels were nearly the same... Have read that it can reduce energy levels and cause some other problems and have read a lot of people say that they live pretty sedentary lifestyles...

    Family history is high cholesterol -- I don't know if my cholesterol has ever been checked before. My doctor seems to think that the low cholesterol is very good, but I'm starting to wonder.
  11. Aug 22, 2009 #10


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  12. Feb 18, 2010 #11


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    Well - apparently what we've been told about good / bad cholesterol is not entirely accurate.

    Bad cholesterol: It’s not what you think
    It's time to rethink the halo-and-pitchfork view of our blood fat levels


  13. Feb 22, 2010 #12
    Check with your MD. Get a second opinion from a different, reputable, MD. Many times a person is not put on statins only because cholesterol levels. There are other significant markers which play a role in diagnose, and they are all correlated. Some of the important markers are HDL / LDL , triglyceride levels, clinical signs of CV disease, aggravating factors such as hypertension, diabetes, family history of hearth disease.

    Ive heard reputed cardiologists said that we should forget determining total cholesterol and rather, diagnosis should be made on
    total Apolipoprotein B . (rather than LDL levels, which only serve as an paroximation of AlipoB )

    Anyway, get a second opinion.
    Last edited: Feb 22, 2010
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