Adding taurine to the feed of 44-week-old laying hens increases polyunsaturated fats in egg yolks, improves egg white quality as measured by albumen height and Haugh units, and lowers yolk...
Mechanism
Synthesis from 1 study
Taurine tells the hen's liver to stop making so much cholesterol and to flush out what it has, while also making more healthy fats. This means the egg yolk gets less cholesterol and more good fats, and the egg white becomes firmer because the whole egg-making process works better.
Most probable mechanism
Taurine tells the liver to make less cholesterol and more healthy fats, while also pushing out excess cholesterol as waste. This means less cholesterol ends up in the egg yolk, and more healthy fats get packed into it. The egg white also becomes thicker because the overall egg formation process becomes more efficient.
Taurine enters hepatocytes and suppresses the expression of SREBP2, a master regulator of cholesterol synthesis
Reduced SREBP2 decreases expression of HMGCR, the rate-limiting enzyme in cholesterol biosynthesis, lowering hepatic cholesterol production
Taurine upregulates ABCG5, increasing cholesterol excretion into bile and reducing the hepatic cholesterol pool
Taurine increases ACAT2 expression, converting free cholesterol into cholesteryl esters for storage or lipoprotein packaging, reducing free cholesterol availability
At higher doses, taurine upregulates CYP7A1, accelerating conversion of cholesterol into bile acids for intestinal excretion
Reduced hepatic cholesterol availability limits cholesterol transport to the ovary and incorporation into developing oocytes
Taurine enhances hepatic production or preservation of polyunsaturated fatty acids C18-3n and C18-2n, increasing their circulation for uptake by the ovary
During vitellogenesis, yolk precursor proteins bind circulating polyunsaturated fatty acids and deliver them to the oocyte, increasing yolk PUFA content
Improved albumen quality results from enhanced protein organization and water retention in the egg white due to altered yolk composition and systemic metabolic efficiency
Evidence from Studies
Supporting (1)
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Effects of dietary taurine supplementation on polyunsaturated fatty acids, cholesterol, and egg quality of egg of hens
Contradicting (0)
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Gold Standard Evidence Needed
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