Problems with Supplements: Many PWP... - Parkinson's Movement

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Problems with Supplements

Many PWP take several supplements and I'm one of them, but as more research is done or I come across research I haven't seen before, I find out that a supplement may have a negative effect on PD or health in general. I'm starting this thread to share and discover more about these sometimes tricky things we call 'supplements'.

I'll start with one that many PWP take, and I used to take: Carnitine. Carnitine is used by our bodies in many helpful ways, so why not take more of it? We produce Carnitine, so there's no known requirement to take in more. But what's the problem if we do?

Briefly, it's now well established that we all have bacteria in our guts that break down whatever we ingest. Some of these bacteria convert Carnitine they find in our guts into TMA, trimethylamine. TMA is converted in our livers to an extremely inflammatory molecule: TMAO, trimethylamine-n-oxide, which then circulates throughout our bloodstream. This doesn't happen in the same way to Carnitine that we produce ourselves because that never gets into our guts where these bacteria live.

Carnitine is also in red meat, so if you cut down on red meat, you're also cutting down on your body's TMAO load and the system-wide inflammation it causes. It's interesting that long-term vegans don't have the bacteria that breaks Carnitine down into TMA, but if they begin taking Carnitine supplements, it grows in their guts too, and then they have the same problem. Vegan or not, Carnitine is not a healthy supplement to take, at least orally

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You're right and I'd forgotten about this. The article you link also says that similar molecules have the same problem because gut bacteria can turn the choline found in eggs, poultry, fish, dairy, and lecithin supplements into TMA too, so it’s not just a problem with red meat. Not to rub it in, but we vegans don't have this problem, unless - as you said - we take carnitine or lecithin supplements.

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From the link: "A landmark study in the New England Journal of Medicine shows that choline in eggs ... produces the same toxic TMAO as carnitine in red meat, which may help explain plant-based protection from heart disease."

Actually no, it does not explain it at all, because a study of outcomes for moderate egg consumers showed that they had better cardiovascular outcomes than non-egg consumers. Studies of outcomes are better evidence than biochemical studies that focus on only one piece of the picture.

Results ...Compared with nonconsumers, daily egg consumption was associated with lower risk of CVD (HR 0.89..). ... Daily consumers also had an 18% lower risk of CVD death and a 28% lower risk of haemorrhagic stroke death compared to nonconsumers. Conclusion ... a moderate level of egg consumption (up to <1 egg/day) was significantly associated with lower risk of CVD, largely independent of other risk factors.


News outlets love sensational headlines, but you have to look more closely. This is a portion of the critique which can be found here:

"In this case, those who consumed fewer eggs were, on average, also consuming fewer fruits. Lastly, they also suffered from higher rates, on average, of both hypertension and smoking. In other words, this study compared people with a higher rate of hypertension and smoking but lower education/income level and lower consumption of fruit and eggs to those with less hypertension and smoking but higher education/income level and higher fruit/egg consumption. And that’s not even to mention other confounding variables."


"throughout the original study report, the authors refer to those who ate the least eggs as “non-consumers.” And yet they categorize this group as 0.29 eggs per day (or 2.03 eggs per week). Can this really be classified as non-consumption? Rather than comparing high egg intake (e.g. 14 eggs per week) with no egg intake, the study instead compared those who ate 2.03 eggs per week with those who ate 5.32 eggs per week. Such a narrow scope is both limiting and misleading. With this in mind, the study reported that those consuming 0.76 eggs per day actually had more cardiovascular disease and death than those consuming 0.56 eggs!" led with: “BMJ’s scrambled message on eggs and heart disease: a recipe for rotten news coverage”

MedPage included a vlog by F. Perry Wilson assistant professor of medicine at the Yale School of Medicine titled: “Eggs Are Good for the Heart… or Not. Here’s why dietary epidemiology research can be rotten.”


"Although this study reports that eggs may be beneficial for heart disease, many others have reported that eggs may not be beneficial. Others still have reported that eggs may even be harmful! Until randomized, controlled trials prove that eating eggs is healthful with regards to heart disease, we should remain cautious about large studies which have inherent flaws, and so too remain cautious about the news outlets reporting on them..."

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From my limited subjective perspective - even though I love eggs I am trying to avoid them since my food sensitivity testing surprisingly revealed high sensitivity to them even though I've had no obvious symptoms. My other family members' tests has shown extreme sensitivity as well which our doctor explained saying that many people are sensitive to eggs because eggs are used as a medium to grow vaccines.

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I take Acetyl-L Carnitine, a "cousin" of Carnitine. It works synergystically with R-Lipoic Acid (or Alpha Lipoic Acid) as a powerful antioxidant and improves mitochondrial function. Not the same as Carnitine or L-Carnitine. It confused me at first so I wanted to post this, in case others are taking Acetyl-L Carnitine and are concerned by this post.


Thanks for the link to the Baseline of Health article, rebtar.

It's always interesting to see how these things go back and forth, with one "side" saying X, therefore, Y, then the other "side"... well, you know how it goes.

If you follow this conversation back to where it started, it was the anti-cholesterol people who first claimed that LDL cholesterol was THE thing to watch out for. Then a meta-analysis pointed out that there were people with relatively low (but not optimal) cholesterol levels who were still having heart attacks. The pro-cholesterol people said this disproved all the previous studies (it didn't, but it did point out that there was something else going on too).

Then new studies investigated this link between consuming carnitine and TMAO and heart disease. To be clear, the Baseline article might well be right about Acetyl-L Carnitine being OK. But it's wrong about TMAO; this molecule has been seen in other heart studies as being part of the inflammation that can trigger heart disease. I'll do some digging to find that info.

Watch this space for the next part of this on-going conversation!


All things in moderation




The thing that leaves me scratching my head about the TMAO thing is that the highest dietary source of pre-formed TMAO is fish. Fish consumption is associated with reduced all-cause mortality.

Here's are a couple of articles that consider the issue:

OTOH, red meat contains N-glycolylneuraminic acid (Neu5Gc), which promotes inflammation; chronic inflammation underlies many disease processes:


Oh, if only things were still that simple.


Overall, I support most of Greger's diet recommendations, but he is way off base on fish. He tries to draw a causal connection between AD and fish consumption when the epidemiological evidence is in direct opposition. He even cites one major epidemiological study on all-cause mortality and diet associations [1, see Fig.2] in one of his videos [2] in support of whole grains and legume consumption, but leaves out the finding (cropped Fig. 2) showing the association between fish consumption and reduced all-cause mortality .

Despite the possible contaminants (mercury, dioxins, PCBs), oxidized cholesterol (not that there's much cholesterol in fish to begin with), and what not - eating fish once a week (baked or broiled, not fried) is associated with reduced AD risk [3]. Fish consumption was even found to be associated with higher IQ in children in China (presumably quite contaminated from all the pollution) [4]. Of course, correlation does not mean causation, but if fish consumption were overall harmful to the brain, these associations with beneficial outcomes would likely not exist.

[1] -

[2] - can't find it since my old desktop crashed and it has all my bookmarks; will cite when computer is fixed (I hope it is fixable)

[3] -

[4] -

Many of these associations are thought to be due to the omega-3 content of fish, but studies of supplementation with omega-3's have produced overall rather underwhelming results. Other beneficial constituents of fish/seafood may be niacin, selenium, taurine, or beta parvalbumin (particularly relevant for PD [5]). It may be that in the case of fish, as with many plant foods, the whole is more than the sum of its parts.

[5] -


Thanks. I agree that the case against fish is weaker than for other animal foods. But there are concerns that add up. Contaminants aside (I wish) fish is still a source of cholesterol, contains choline which can lead to TMAO, and all animal proteins are higher in leucine and methionine amino acids than plant proteins. But, as you say, I know of no large scale epidemiological studies that suggest eating fish increases all-cause mortality. The only study that comes to mind is the Adventist study which showed vegans had lower BMI and lived slightly longer than pescatarians. And the Okinawans had a very small amount of fish in their diet, but it was still there.

"If you look at the traditional diets of more than 2,000 Okinawans, it breaks down as follows: Only 1% of their diet was fish, less than 1% of their diet was other meats, and less than 1% was dairy and eggs, so it was more than 96% plant-based and more than 90% whole food plant-based as they ate few processed foods."

So I don't see a huge health benefit in not eating a little fish, unless you (like me) don't want to risk contamination which is constantly increasing.


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