On Nutrition

DEAR DR. BLONZ: Regarding your answer about the ability to smell asparagus in urine, you had said “the ability to perceive the odor is determined by one’s genes.” Whose genes? The person producing the urine, or the person doing the smelling? Along this line, my wife seems to have “smell genes.” She accuses me of not bathing and wearing dirty clothes the day after I have eaten a salad with Italian dressing on it. How common are these “smell genes” in the general population? -- F.M.

DEAR F.M.: My apologies for any confusion. A sulfur compound gets produced in all who consume asparagus; it comes from a normal breakdown of the asparagusic acid found in varying levels in asparagus. Certain genes are needed for an individual to detect this odor.

As regards the second part of your question, several alterations can occur in the sense of smell, ranging from anosmia (loss of the sense of smell) to dysosmia (alteration or distortion in the sense of smell) to hyperosmia (enhanced sensitivity to odors). Attention should be paid when there are unexpected changes in the sense of smell (or taste). I’m unsure if the situation you describe is one you have always had to live with, or if it is something that recently emerged. If the former, then the two of you have to rely on your own strategy. But if a change in your wife’s sense of smell (or taste) is something that developed recently, then consider having it evaluated medically. A physician can determine whether it is the product of some event or ongoing process that needs to be better understood. More on this at b.link/taste81.

DEAR DR. BLONZ: I read your advice about the tolerable upper limits of copper and zinc. Currently, I am taking supplements called PreserVision AREDS 2 by Bausch + Lomb. Although I don’t have glaucoma or AMD (age-related macular degeneration), my mother had both. I do have medical issues with my eyes, just not those suffered by my mother.

I am taking one pill a day, though the directions say to take two. Each pill contains 40 milligrams of zinc and 1 milligram of copper. The main reason I’m taking the one pill is that it also contains 5 milligrams of lutein and 1 milligram of zeaxanthin, but now I wonder if the zinc isn’t too much. Should I stop taking them? -- C.E., Freemont, California

DEAR C.E.: A key issue with zinc and copper arises when one is present, and the other is not. This is made worse if one is present in excessive amounts in the absence of the other. The AREDS 2 supplement provides both zinc and copper, so that issue does not present itself.

I thank you for this question, and I hope this serves as a clarification of the point, so that others who might be taking this or similar products will not be concerned. Also, give a read to this article on vision supplements: tinyurl.com/yxmybl7r.

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.

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