Another Reason Why Eggs Actually Lower the Risk of Heart Disease

Although folic acid and to a lesser extent vitamins B-6 and B-12, are known to be able to reduce levels of homocysteine, researchers from the Netherlands report of another nutrient-betaine, found mostly in eggs and liver also has this capability.  They note that elevated plasma total homocysteine concentrations are considered a risk factor for giving birth to a child with neural tube defects and for cardiovascular disease.

Just like folic acid, betaine facilitates the remethylation of homocysteine into methionine. However, the researchers note that " ... the folate-dependent remethylation takes place in all cells, whereas the betaine-dependent remethylation reaction is mainly confined to the liver."

According to the authors, eggs and liver are the best food sources of betaine.  Additionally, they note that betaine has been shown to substantially decrease homocysteine levels in patients with a condition known as homocystinuria, and they therefore theorized that it could have the same benefit in healthy patients as well.

The authors conclude that "Betaine supplementation decreases plasma total homocysteine concentrations in healthy volunteers." However, the extent of the decrease is much smaller in healthy volunteers than in patients with homocystinuria. In such patients, with plasma total homocysteine concentrations above 50 μmol/L, betaine supplementation significantly lowered plasma total homocysteine concentrations, by up to 75 percent." 
However, they note that "The homocysteine-lowering effect seems smaller than that established by interventions with folic acid."

Betaine, also known as trimethylglycine, is produced by the body from choline and also from the amino acid glycine.