Zinc

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Re: Zinc

Postby JeffN » Thu Apr 02, 2009 10:58 am

Carroll wrote: Also, do you know how we can easily up our zinc absorbtion or intake without the supplements? Do zinc needs increase with breastfeeding and maybe puberty?


Hi Carroll

The DRI for zinc for adults males is around 11 and for adult females is 8. And, for many, especially on a vegan or vegetarian diet, it may seem difficult to achieve.

However, if you read the full FAO report on zinc you find out that the actual need is around 4-11 depending on many other factors. I think you may enjoy reading this report.

http://www.fao.org/docrep/004/Y2809E/y2809e0m.htm#bm22

So, many of us, who are eating very healthy, may be "aiming' for a DRI of zinc that is not applicable to us and we may need much less.

The EAR, or estimated average requirement for zinc is 9.4 mgs for men and 6.8 mgs for women.

The difference between the 2 is the EAR is closer to the actual need and the RDA has built in buffers, which raise the recommended level to try and cover all the situations of about 98% of the population.

The best way to increase your Zinc intake, if that is your goal, is to increase the food that are the highest in zinc "density" which is the amount of zinc per calorie.

Zinc (Per 100 calories)

Calabash, cooked, boiled, drained, with salt Zinc: 5.4 mg
Endive, raw Zinc: 4.5 mg
Bamboo shoots, cooked, boiled, Zinc: 4.5mg
Bamboo shoots, raw Zinc: 4 mg
Mushrooms, brown, Italian, or Crimini, raw Zinc: 4mg
Alfalfa seeds, sprouted, raw Zinc: 4mg
Squash, zucchini, baby, raw Zinc: 4mg
Chayote, fruit, raw Zinc: 4mg
Broccoli raab, raw [Broccoli rabe, Rapini] Zinc: 3.5mg
Spinach, cooked, boiled, drained, without salt Zinc: 3.5mg
Mushrooms, cooked, boiled, drained, with salt Zinc: 3mg
Asparagus, cooked, boiled, drained Zinc: 3mg
Beans, kidney, red, mature seeds, canned Zinc: 3mg
Beans, adzuki, mature seeds, raw Zinc: 1.5mg
Wild rice, cooked Zinc: 1.5mg
Oat bran, cooked Zinc: 1.5mg
Seeds, pumpkin and squash seed kernels, dried [pepitas] Zinc: 1.5mg
Seeds, sesame seeds, whole, dried Zinc: 1.5mg
Wheat, durum Zinc: 1mg
Rye Zinc: 1mg
Triticale Zinc: 1mg
Oats Zinc: 1mg
Quinoa, cooked Zinc: 1mg
Millet, cooked Zinc: 1mg

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Postby JeffN » Fri Apr 03, 2009 8:08 am

Carroll wrote:I eat a lot of those foods (except the calabash, chayote, and napa cabbage... I eat a lot of cabbage though, napa isn't always as available?) but we still experienced that very obvious deficiency. As I mentioned I wasn't concerned about not reaching that higher RDA until we all started experiencing the underarm odor and taking the zinc supplement completely solves that... does the link address the absorption issue? I couldn't get that link to work.


While I know you are very careful about what you eat, eating "a lot" does not always equate to "enough." The only way to know for sure is to do the analysis. If you posted the analysis of a full weeks intake showing that you had analyzed it and compared your average intake to the RDA's/DRI's, we would have a more accurate basis to go on.

While I appreciate your experience and glad you have resolved the issue, your experience does not prove that you were zinc deficient. Taking medications and /or supplements may resolve some issues, but in and of itself, it does not mean that a deficiency was present. Zinc is known to kill bacteria that cause body odor but this does not mean the bacteria are due to a lack of zinc of a zinc deficiency. In addition, the form of zinc that is know to kill these bacteria is also known as a skin and respiratory irritant according to its MSDS.

http://www.jtbaker.com/msds/englishhtml/z2280.htm

Yes, I would recommend reviewing the paper as it discusses all the variables involved in setting recommended levels including absorption related issues. Understand that the US recommendations already take most of these issues into consideration.

Here is the proper link

http://www.fao.org/docrep/004/Y2809E/y2809e0m.htm#bm22

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Postby JeffN » Fri Apr 03, 2009 2:05 pm

Carroll wrote:Wow, after reading that link I'm even more concerned... I didn't realize about the stunted growth and immunity issues. It did indicate both a higher need during puberty and while breastfeeding as well as needing a higher intake on a plant based diet due to low absorption issues... so it really sounds like supplementing yet another item may be necessary for us.

I can't remember my login to access my info I had online from when I started tracking everybody while I was pregnant but for the last ten days using the chron-o-meter my 13yo got 9.8, 12.6, 13.2, 6.2, 5.9, 7.8, 6.6, 11.1, 8.2, & 10.8mg of zinc ... which I thought wasn't too bad (better than the rest of us seem to do), however now reading that link it looks like her RNI is 14.4.


The absorption issues have to deal with the type of food consumed regardless of whether one is on a plant based diet or not. And again, realize that they already take most all of this into consideration when making their recommendations for individual regions.

As I mentioned above, my reading of this material along with the material from the NAS shows me that if anything I am much less concerned and the the recommended numbers are too high if anything and not low.

Here is the one from the NAS

http://www.nap.edu/openbook.php?record_ ... 6&page=442

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