Worrying about vegans and heart disease

Our ability to make taurine is not very good – better than cats’ ability by far, but nothing compared to rats’ ability.

As far as we know, taurine is found only in animal products, which is why cats are obligate carnivores in a state of nature – seafood especially, beef secondarily, and other meats and cow’s milk tertiarily.

As taurine deficiency proceeds in humans, the first effect is likely on reduced absorption of fats and fat soluble substances, of which there are 4 important classes to keep in mind:

  1. Fat-soluble essential nutrients (at least four – vitamins A, D, E, and K).
  2. Fat-soluble conditionally essential nutrients (basically what we have suboptimal levels of at any of thousands of distinguishable locales within our bodies).
  3. Essential fatty acids (18:2 omega 6; 18:3 omega 3)
  4. Conditionally essential fatty acids

This is serious, but the next stage would involve cardiomyopathy and retinopathy – much more serious. Since cats cannot make glycine bile acids as well as we do, cats deficient in taurine proceed quickly to cardiomyopathy and retinopathy.

Consider the following results from a PUBMED search. For the most part, the references tell a consistent story about taurine and cardiovascular health, but of course do not rise to the level of a completely silly over-simplification – taurine deficiency causes cardiomyopathy:

Taurine[title/abstract] AND ischemic heart disease[title/abstract]:
1: Xu YJ, Arneja AS, Tappia PS, Dhalla NS. The potential health benefits of
taurine in cardiovascular disease. Exp Clin Cardiol. 2008 Summer;13(2):57-65.
PubMed PMID: 19343117; PubMed Central PMCID: PMC2586397.

2: Yamori Y, Liu L, Mori M, Sagara M, Murakami S, Nara Y, Mizushima S. Taurine as  the nutritional factor for the longevity of the Japanese revealed by a world-wide epidemiological survey. Adv Exp Med Biol. 2009;643:13-25. doi:
10.1007/978-0-387-75681-3_2. PubMed PMID: 19239132.

3: Luna Ortiz P, Serrano Valdés X, Rojas Pérez E, de Micheli A. [Metabolic
support of the ischemic heart during cardiac surgery]. Arch Cardiol Mex. 2006
Oct-Dec;76 Suppl 4:S121-36. Review. Spanish. PubMed PMID: 17469340.

4: Yamori Y, Liu L, Mizushima S, Ikeda K, Nara Y; CARDIAC Study Group.. Male cardiovascular mortality and dietary markers in 25 population samples of 16 countries. J Hypertens. 2006 Aug;24(8):1499-505. PubMed PMID: 16877951.

5: Yamori Y, Liu L, Ikeda K, Miura A, Mizushima S, Miki T, Nara Y;
WHO-Cardiovascular Disease and Alimentary Comprarison (CARDIAC) Study Group.. Distribution of twenty-four hour urinary taurine excretion and association with ischemic heart disease mortality in 24 populations of 16 countries: results from  the WHO-CARDIAC study. Hypertens Res. 2001 Jul;24(4):453-7. PubMed PMID: 11510759.

6: Kennergren C, Mantovani V, Lönnroth P, Nyström B, Berglin E, Hamberger A. Extracellular amino acids as markers of myocardial ischemia during cardioplegic heart arrest. Cardiology. 1999;91(1):31-40. PubMed PMID: 10393396.

7: Yamori Y, Nara Y, Mizushima S, Sawamura M, Horie R. Nutritional factors for stroke and major cardiovascular diseases: international epidemiological
comparison of dietary prevention. Health Rep. 1994;6(1):22-7. English, French.
PubMed PMID: 7919085.

8: Wilcken DE, Reddy SG, Gupta VJ. Homocysteinemia, ischemic heart disease, and the carrier state for homocystinuria. Metabolism. 1983 Apr;32(4):363-70. PubMed PMID: 6684724.
9: Gagliarducci U. [Treatment of acute ischemic heart disease using taurine.
Clinical study of 30 cases]. Clin Ter. 1974 Feb 15;68(3):261-70. Italian. PubMed PMID: 4596252.

Here is Figure 2 from reference #5 above:

taurine-excretion-and-ihd-mortality-risk

This correlation is probably just another mindless correlation that means absolutely nothing. Who cares that the data are from 24 populations in 16 different countries and that the correlation is hyperbolic? The graph is weird. People excreting 600 micromole of taurine a day can have mortality rates <200 or as high as 1000 per hundred thousand. But by the time the excretion is at least 1200 micromole per day, the curve normalizes and the risk of heart disease is consistently less than 5x the rate at the lowest excretions pictured.

But with no daily intake of taurine to speak of, are vegans excreting anywhere near 1200 micromole of taurine per day in their urine? Does something else in their diet make up for the lack of this one nutrient and the many other animal-specific nutrients that they may be deficient in?

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s