L-lysine, or just lysine, is bandied about for rosacea in some circles. It may be useful for viral infections, so could this work for rosacea?
It makes some sense that lysine might have a role in preventing herpes simplex virus (HSV) cold sore outbreaks because HSV requires arginine to reproduce. Lysine is a antagonist of arginine through multiple potential mechanisms.
Studies have been somewhat conflicting, but if lysine is effective in HSV at all, it appear that it is in preventing outbreaks rather than treating an active cold sore.
Rosacea is not a viral infection, so what does this have to do with rosacea? Nothing that I can find, and I searched all the published research, not the heresay on the internet. Lysine is an essential amino acid, which means you must get it from your diet. And foods high in lysine include proteins like red meat, chicken, cheese, and yogurt, so unless you are a vegetarian, you probably get plenty of lysine.
The other side of the coin here is that too much lysine stimulates growth hormone. That's why body builders take it in high doses, but the downside of growth hormone is that it stimulates keratin production, which clogs pores. You might be buying yourself some acne in an attempt to prevent rosacea.
Another idea is to decrease the foods you eat that contain arginine since lysine competes with it.
If you think lysine could help you, don't overdo it and don't take it forever. Take no more than 1.5 g/day for a month or two, and see if it helps you. And buy it from a company that follows good manufacturing practices (GMP) for quality.
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