‘Healthy’ cholesterol-reducing compounds found to be toxic to heart cells

‘Phytosterols’ are compounds that can impair the absorption of cholesterol from the gut. In this way, ‘sterols’ (as their name is often abbreviated to) can reduce cholesterol levels in the bloodstream, which conventional wisdom dictates is always a good thing. Sterols are added to ‘functional foods’ including special margarines that promise cholesterol-reducing and, therefore, health-enhancing properties.

However, the reality is that the impact a drug or foodstuff has on cholesterol levels is quite irrelevant – it’s its impact on health that is important. This distinction is critically important: Arsenic and cyanide might reduce cholesterol levels, but that does not make them healthy things to consume.

I was interested to read about a recent study in which the effect of sterols on rat heart cells was assessed [1]. The cells were exposed to levels of sterols commonly found in the bodies of individuals ingesting sterols. The cells ended up incorporating the sterols at the expense of cholesterol. However, at the same time, the metabolic activity of the heart cells decreased, as did their capacity for growth. In short, exposing heart cells to sterols appears to, err, poison them.

The authors point out, that the results of this study cannot necessarily be translated into conclusions about the effect of these compounds on heart health, but add that the findings “raise[s] concerns about the safety of long-term exposure to physiologically relevant PS [phytosterol] concentrations.”


1. Danesi F, et al. Phytosterol supplementation reduces metabolic activity and slows cell growth in cultured rat cardiomyocytes. British Journal of Nutrition 20 April 2011 [epub]

22 Responses to ‘Healthy’ cholesterol-reducing compounds found to be toxic to heart cells

  1. Mark Dillon 25 April 2011 at 8:24 am #

    Thanks for the article, yet another reason to avoid flora pro-active!

  2. MrWeetabix 25 April 2011 at 9:02 am #

    Definately, why use spreads anyway..

    However, Beta-Gluten is Oats is of good health benefits, as are the cholesterol reducing substances in beans

  3. Justmeint 25 April 2011 at 9:50 am #

    Thanks again Dr. Briffa…. I feel somewhat vindicated…. have blogged about this tonight, with a link to this article.


  4. Dan 25 April 2011 at 2:16 pm #

    I also saw somewhere the excessive plant sterols may cause aortic stenosis.

    Plant sterols may very well become the next trans fat – promoted for cholesterol, but causing more problems.

  5. Jake 25 April 2011 at 6:29 pm #

    Dr William Davis, the famed cardiologist, recommends you avoid plant sterols.

  6. Justmeint 25 April 2011 at 11:29 pm #

    I already said I will not use plant sterol type supplements, but this AM I found the following Australian Article which says they do not work anyway! WASTE OF MONEY! heheheh


  7. J. Stanton - gnolls.org 26 April 2011 at 3:36 am #

    Our bodies have enzymes dedicated to keeping plant sterols OUT of our bloodstream (sterolins), and our liver filters plant sterols out of our bloodstream as fast as it can.

    In other words, our body treats them as poisons.

    Perhaps there is a lesson to be learned here…?


  8. Bev Carney 26 April 2011 at 10:23 pm #

    My husband has been taking Red Yeast Rice and it is now ‘improved’ with the addition of plant phytosterols. Most worrisome!

  9. Ed Terry 27 April 2011 at 10:09 am #

    Ratnayake WMN, “Influence of Sources of Dietary Oils on the Life Span of Stroke-Prone Spontaneously Hypertensive Rats”, Lipids, Vol 35, no.4, 2000

    The study showed a positive association between saturated fat and longevity. In addition, the phytosterol content of vegetable seed oils was inversely associated with longevity.

    Seems that red blood cells prefer cholesterol over phytosterols when membrane integrity is considered.

  10. MrWeetabix 27 April 2011 at 11:07 am #

    TThe dairy industry also contributed to the above study….a bit biased don’t you think

  11. Angie M 29 April 2011 at 12:54 pm #

    oh dear….having just been told I have a cholesterol level of 9 (!!) despite exercising three times a week and not smoking, I started a programme of high level plant phytosterols….do I now give them up? Have given up dairy, not sure what else I can to lower ch??

  12. John Walker 29 April 2011 at 1:08 pm #

    I wouldn’t spread axle-grease on my bread; if I ate bread that is. Flora? Stork? Call it what you will. It’s rancid rubbish, not fit to throw away! It clogs up the drains you see.


  13. Gabriella 29 April 2011 at 3:30 pm #

    Dear Angie M. –
    I too have what the mainstream doctors consider “high cholesterol”. I am Italian and come from a family of “high cholesterol”, long-living individuals. Both of my parents lived well into their 90’s!
    I told the doctor who recommended statins to me to lower my cholesterol that, no thanks, I’ll keep my cholesterol. She, the doctor, fired me as patient! Good riddance (of the doctor) I said.
    Anyway, I would advise you to check this website as regards cholesterol and the other “arch-enemies”, saturated fats. You will be surprised at what you will find.
    Here is the link: http://www.westonaprice.org/component/finder/search?q=cholesterol
    Cheers in good health, Gabriella

  14. Angie M 29 April 2011 at 3:55 pm #

    Gabriella, many thanks – you have cheered me up! I am also of Italian origin so maybe that is affecting things. I refuse to take statins too and wary of the whole industry. All my family (Italian side) have high cholesterol yet no-one has ever had a heart attack or stroke! Ciao and grazie,

  15. Galina L 29 April 2011 at 9:45 pm #

    There is no correlation, anyway, between high cholesterol level and hard attack in women. Why not paying attention to triglycerides and HDL, or fasting BS, or blood pressure?

  16. Daniel Cooley 30 April 2011 at 2:07 am #

    Why is Dr Briffa reporting a rat study as being applicable to humans by using misleading headlines and inflammatory words such as “poison” and “toxic”. The rat study itself cannot be repeated yielding the same results. The total well-being of humans vis a vis sterols remains unknown.

  17. Clare C 5 May 2011 at 7:31 am #

    For more on the lack of evidence for benefits of plant sterols and indications of possible dangers see the following papers. Certainly there is a need for more research.

    Weingärtner O, Böhm M, Laufs U. Controversial role of plant sterol esters in the management of hypercholesterolaemia. Eur Heart J 2009; 30: 404-409;

    Weingärtner O, et al. Plant sterols as dietary supplements for the prevention of cardiovascular diseases. Dtsch Med Wochenschr 2008; 133: 1201-4.

  18. John Briffa 5 May 2011 at 1:25 pm #

    Thanks Clare

    I, by coincidence, read the first of these studies yesterday and will post something about it soon.

  19. nadjushka 21 May 2011 at 10:46 am #

    I have followed the discussion about the possible toxicity of plant sterols for a long time. Please, also have a look at the following paper from Germany


  20. nadjushka 21 May 2011 at 10:48 am #

    This review is also interesting to read.


  21. Sifter 10 July 2011 at 6:11 am #

    You should send this to Clarence Bass http://www.cbass.com, he’s always touting Benecol and other sterol spreads.


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