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  1. My question concerns the use of zinc and vitamin C to enhance a man's fertility. My husband and I are currently trying to have a baby. Answer
  2. What is the difference between chelated zinc and zinc picolinate? Answer

My question concerns the use of zinc and vitamin C to enhance a man's fertility. My husband and I are currently trying to have a baby and he was advised to supplement his diet with vitamin C and zinc. Is there any scientific merit to this advise and if so, how much of each should he take each day?

An adult male's (25+ years of age) Recommended Dietary Allowances for zinc is 18 mg per day and vitamin C is 60 mg per day. It would not be wise to take excess zinc as it suppresses copper and calcium absorption. Copper is necessary for hemoglobin formation in red blood cells, enzymes and collagen (connective tissue). Excess Vitamin C will turn urine yellow and acidify urine, which can decrease kidney infections.

I would suggest you consult both your doctors on the issue of fertility. Male testicles do not like to be close to body temperature and prefer it cooler. Sometimes close fitting underwear and jeans can also interfere with male fertility. Switch to loose underwear like boxers and loose slacks.

First, what is the difference between chelated zinc and zinc Picolinate? Are these different manufacturing processes for the tablets? Is one better than the other?

Am I in for trouble taking that much zinc?

Finally, what could cause a zinc deficiency and possible effects of a zinc deficiency?

Thanks much.

Chelated minerals are bound to a compound and depending on what that compound is may be not absorbed well. Zinc Picolinate is a compound. I would suggest you consult a pharmacist regarding the most absorbable form for zinc.

Zinc deficiency would result from inadequate intake since most zinc is found in liver, kidney, pancreas and the brain and not lost through blood, urine or feces. Persons on total parenteral nutrition (IV's that contain glucose, amino acids and fat) also can develop deficiencies if not supplemented through the IV fluids. Birth control pills can also lower blood levels of zinc and calcium. However, phytates (found in whole grains and beans) bind zinc and prevent absorption. Have you been eating a very high fiber diet with large quantities of the above foods?

Deficiency symptoms include changes in taste and smell or a loss of appetite and retarded sexual maturation. While a zinc deficiency can cause insignificant changes in hair and skin, hair analysis can be unreliable to determine nutrient status in the body. Saliva can also be analyzed for zinc levels.

In addition to the zinc supplement you take, you are getting additional zinc in the multivitamin probably equal to 100% of the Recommended Dietary Allowances or an additional 15 mg. The quantity of zinc supplements you are taking will suppress copper, which is a necessary component of red blood cells. You could become anemic continuing with the zinc supplements. Your RDA for zinc is 15 mg per day. You are taking over 600% of your RDA and I would suggest you stop.

Foods that are high in zinc are oysters. Moderate food sources are seafood, meat (beef, liver, turkey and dark meat of chicken) or dairy products. Vegans have lower zinc levels.

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