vitamin D

want to start today's column by thanking all of you for your continued interest, questions and comments. There are so many good points all of you have to share, and given space constraints, it can be hard to do justice to all of them. But today I'd like to pass on some of your important feedback.

Q: I read about plant sterols lowering LDL cholesterol in your May 20 article. I would like to know what the brand name of the plant-sterol-based "chews" is and where I could find them.

A: Benecol is one brand that makes caramel chews with 0.85 grams of sterols. You can find them online or at a health food store.

Q: Gee, what about red rice yeast for lowering cholesterol?

A: Several good studies have been done on red rice yeast showing that it helps lower cholesterol. Although some of the research suggests that it raises HDL and lowers triglycerides and LDL, my clinical experience is that it is very effective mainly for lowering LDL.

Q: I read your article on home remedies for cold sores. My mom always put baking soda on cold and canker sores, but only after the skin broke. The sores did seem to heal faster.

A: Thank you for sharing that information. Baking soda is an effective natural cleaning product, too.

Q: From my reading, there are few actual facts on the negative effects of vitamin D. The recommended daily allowance (RDA) is based on mostly inadequate research. The warnings about vitamin D and kidney problems that most doctors cite are based on studies associated with calcium problems in a specific population of patients. That is being rethought as even kidney patients may benefit from vitamin D.

A: I think you bring up some good points. The U.S. RDA (now actually, the Adequate Intake or AI) was originally based on the amount of vitamin D found in 1 teaspoon of cod liver oil, because that is what parents had found prevented rickets (weakened bones) in their kids.

Recently, researchers have recommended these levels be changed, because there is data suggesting that the vitamin D blood levels we have been targeting for years are too low. The concern has been that too high an intake of vitamin D can cause high calcium in the blood, which can then deposit in body tissues, including the kidneys.

However, it is true that the threshold for negative effects is probably much higher than previously thought — as long as we are talking about cholecalciferol, or vitamin D3. Other forms of vitamin D, such as calcitriol, are toxic in lower doses.

Also, patients with kidney disease are often treated with a prescription form of vitamin D because they may not make enough on their own. However, that does not prove that vitamin D cannot cause calcium deposits in the kidney in too high a dose.

source:seattletimes.nwsource.com