Thursday, April 21, 2011

Phytosterols: ‘little value’ for metabolic syndrome, toxic to heart cells

UPDATE: 27 April, 2011 - Phytosterols 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.”
References:
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

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It is cold and wet today where I am but I am happier than a clam.

Someone finally decided to look at an issue I've been talking and writing about for quite a few years and they are finding cause for concern.

I hope you take this as seriously as I do because plant sterols are sourced from GMO soy and canola oil. Outside the fact they are GMO, neither are good for your health.

By Nathan Gray, 19-Apr-2011
Related topics: Phytochemicals, plant extracts, Cardiovascular health, Research

The cholesterol lowering effects of phytosterols may have little effect on the lipid profile of people with metabolic syndrome, according to new research.

The study, published in Clinical Nutrition, suggests that the reduced cholesterol absorption that is characteristic of metabolic syndrome (MetS) may interfere with the mechanisms of phytosterols cholesterol lowering action – thus reducing their efficacy as a cholesterol lowering agent.
The team of Spanish scientists found that whilst phytosterol enriched foods were able to efficiently lower blood lipid profiles of healthy volunteers, they had no effect on the lipid profiles of volunteers with metabolic syndrome.
“The results of this study demonstrate that MetS subjects with hypercholesterolaemia who consume phytosterols […] do not exhibit any improvement in their lipoprotein profile, suggesting that phytosterol therapy is of little value,” said the authors, led by Dr Antonio Hernandez-Mijares from the University of Valencia, Spain.
MetS risk
Metabolic syndrome (MetS) is a combination of metabolic disorders that promote the development of cardiovascular disease.
“The core components of dyslipidemia in MetS, which are likely to provoke atherosclerosis, are the ‘lipid triad’ of high plasma triglycerides, low levels of high-density lipoprotein cholesterol, and a preponderance of small, dense low-density lipoprotein particles,” explained Hernandez-Mijares and colleagues.
They noted that nutritional modification and lifestyle changes are “the cornerstone of dyslipidaemia therapy.”
Previous research has suggested daily consumption of foods rich in phytosterols may reduce the plasma concentration of LDL-cholesterol.
“Phytosterols are known to reduce intestinal cholesterol absorption, which leads to a significant reduction of serum LDL-cholesterol concentrations (about 10%) without altering HDL-cholesterol or triglycerides when administered at a dose of 2 g/day,” said the authors.
However the effect of the daily consumption of phytosterols for metabolic syndrome is yet to be established, they added:
“There is a lack of relevant data, and the few studies carried out to assess the impact of phytosterols supplementation on MetS subjects are contradictory.”
Hernandez-Mijares and co-workers explained that people with metabolic syndrome often have higher levels of cholesterol, which is accompanied by reduced cholesterol absorption. They suggested that the lower absorption of cholesterol observed in people with metabolic syndrome may interfere with phytosterols’ mechanism of action, therefore reducing their efficacy as cholesterol reducing agents.
The new research investigated whether the addition of low-fat milk enriched with phytosterols in the diet improved cardiovascular risk factors in a group of 24 people with moderately high cholesterol levels and MetS.
Study details
Hernandez-Mijares and colleagues reported that neither a dietary intervention nor enrichment of foods with phytosterols brought about any improvement in the serum lipoprotein profile of metabolic syndrome patients.
In contrast, non-metabolic syndrome participants were found to have reduced levels of total cholesterol, LDL-cholesterol, non-HDL-cholesterol and Apolipoprotein B-100 after both a dietary intervention and enrichment of foods with phytosterols.
“Supplementation produced a significant increase in phytosterol levels only in the non-MetS population,” said the authors.
“The results of the present study show that neither dietetic guidelines nor enrichment with phytosterols improved lipid profile in a hypercholesterolaemic population with MetS. This lack of response appears to be associated with low intestinal cholesterol absorption,” explained Hernandez-Mijares and co-workers.
“This suggests that the cholesterol-lowering effect of phytosterol was undermined when cholesterol absorption was low,” they added.
Source: Clinical Nutrition

Published online ahead of print, doi: 10.1016/j.clnu.2011.03.00 http://dx.doi.org/10.1016/j.clnu.2011.03.005


“Low intestinal cholesterol absorption is associated with a reduced efficacy of phytosterol esters as hypolipemic agents in patients with metabolic syndrome”

Authors: A. Hernández-Mijares, C, Bañuls, A, Jover, E, Solá, L. Bellod et al
Selected posts from Natural Health News

Nov 14, 2007
Foods or dietary supplements containing at least 400 mg per serving of free phytosterols taken twice a day with meals for a daily total intake of at least 800 mg, as part of a diet low in saturated fat and cholesterol, may reduce the ...
Apr 22, 2009
The nuts contain ingredients such as omega-3 fatty acids, antioxidants and phytosterols that may all reduce the risk of the disease. Mice fed the human equivalent of two ounces (56.7g) of walnuts per day developed fewer and smaller
Aug 06, 2008
It isn't just aspirin any more: Phytosterols, Aspirin, Microcrystalline Cellulose, Lactose, Croscarmellose Sodium, Corn Starch, Powdered Cellulose, Pregelatinized Starch, Hypromellose, FD&C Yellow #5 (tartrazine) Aluminum Lake, ...
Sep 12, 2008
Olive oil is not a trans fat like canola (because of the processing of the seed into oil) and it contains Tocopherols (vitamin E), beta-carotene (vitamin A), phytosterols, pigments, terpenic acids, flavonoids (luteolin, quercetin, ...

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