Q: In your recent article about cold sores you did not address the use of lysine, which I hear is pooh-poohed by medical professionals. I use it at the earliest onset of a cold sore, and it works great. Can you say something about it in a future column?
A: While the most reliable treatment of cold sores has come from using anti-viral pills like Valtrex, Famvir or Acyclovir or Denavir ointment, a number of folks insist that taking the amino acid lysine at the first onset of a cold sore can work just as well. Personally, for years I've taken 1 gram tablets 2-3 times a day at the earliest onset of a canker sore/aphthous ulcer with good success. Why it helps for that is not known, but there is a theoretical explanation as to how lysine can treat cold sores, which are caused by the herpes simplex virus. It seems that the amino acid arginine is necessary for the herpes virus to reproduce itself, and taking extra amounts of lysine blocks the action of arginine. Some people take lysine daily as a supplement and insist they never get cold sores or canker sores, but there's little study of this practice. Nonetheless, it's a pretty safe attempt at prevention.
Q: I recently started using agave nectar syrup to sweeten my tea. What do you think of it?
—P.W., Covington, Ga.
A: Agave nectar is a popular honey substitute that's 1.4 times sweeter than sugar, and sweeter and thinner than honey. Folks enjoy this natural sweetener as an alternative to processed sugar and artificial sweeteners. While it looks like a thinner version of honey, it doesn't impart a strong flavor like honey can. In terms of calories, it has 60 calories per tablespoon, versus 46 calories per tablespoon for table sugar.
One thing to be aware of is that if you have an aversion to high fructose corn sweetener, agave nectar syrup actually has a much higher fructose concentration (90 percent fructose) than high fructose corn syrup (55 percent). That said, the amount of fructose-rich agave sweetener that folks like yourself use in their tea is much less than that contained in a bottle of cola sweetened with high fructose corn syrup. Also, while agave nectar is fructose-rich, it actually has a much lower glycemic index than table sugar or high fructose corn syrup. That means, in moderation, it won't be as likely to spike one's blood sugar. That's still going to be much higher than the zero glycemic indices of zero-calorie sweeteners like Spenda, Equal or saccharin.
Dr. Mitchell Hecht is a physician specializing in internal medicine. Send questions to him at: Ask Dr. H, P.O. Box 767787, Atlanta, GA 30076. Due to the large volume of mail received, personal replies are not possible.