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Men's Nutrition Questions Answered

Saw Palmetto, Vanadium and Reliv

Q: I recently had a small seizure after taking super carnosine and carnitine for two weeks. I am on Proscar® and Synthroid®, and I take saw palmetto. Any connection?

A: There's not enough information here to know for sure, but specifically blaming carnosine and carnitine is doubtful. L-carnitine is required to move fatty acids across the mitochondrial membrane for burning as energy, and I'm not aware of any toxicities to carnosine (though anything, even water, can be toxic if you take enough).

Proscar® and saw palmetto do the same thing, though the herb form is far safer. Check with your doc about taking both together. Also, the dose of prescription thyroid is important. Synthroid® has recently (and not so recently) been implicated in multiple problems in humans. I prefer the natural form of thyroid (though still prescription strength), called Armour-type, as it contains all 4 types of thyroid hormone, instead of just one (as in the case of Synthroid®). Check with your doc on that one and make sure you aren't getting too much.

Q: What is vanadium? What is the recommended daily dosage, and what is considered toxic? What is its value? Why supplement an additional 250 mcg a day?

A: Vanadium is a trace element and also a micromineral (a mineral needed in very tiny amounts) for human nutrition.

Though it currently has no established amount needed for human nutrition, studies are consistent suggesting its role in helping with proper glucose metabolism in humans (and animals).

The substance is usually given in a salt form of vanadium called vanadyl sulfate and, like chromium, it apparently augments the effects of insulin, which the body uses to pull glucose out of the bloodstream and into cells.

It doesn't take much; usual doses range from 3 to 25 milligrams/day of vanadyl sulfate (there is no RDA or Recommended Daily Allowance). There are studies done using 100 milligrams/day, but this is excessive.

Some researchers feel the upper limit is 25 milligrams/day, and I see no need to go even that high. Two-hundred fifty micrograms (250)- that's 1/4 of 1 milligram - is a bit low for demonstrable effect, in my opinion, and may be included in a product more to have it on the label than anything else, but that's purely conjecture. Check with your doc.

Q: My husband is 30 years old and has been a diabetic for 23 years. He has taken an interest in a nutritional supplement called Reliv. He has been taking it for a couple of weeks and says he feels pretty good. This company also makes a supplement for children. Our 2-year-old is a very finicky eater and we were interested in providing him with a supplement. What do you know about this product and its maker?

A: Reliv is a proprietary blend of nutrients from non-animal sources, predominantly soy. I have not used the product myself but have heard many anecdotal reports from fellow doctors, patients and body builders concerning their perceived success with it.

The product is nutrient-dense as a food supplement and probably well-absorbed. I am not a big fan of soy so I do not use it, but that's just me.