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Dedicated to spread accurate information on Vitamin / Hormone D


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Treatment of Type 2 Diabetes: One Extreme to Another.


By Sarfraz Zaidi

Arch Intern Med. 2009;169(13):1246-1247.

Official Journal of the American Medical Association

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Vitamin D

This is an Excerpt from Dr. Zaidi's book, "Power Of Vitamin D." Copyright © All rights reserved.

Vitamin D is not actually a vitamin. It is a hormone.

Why Should I Care about Vitamin D?

Because Vitamin D is one of the most effective tools available to you for the prevention of most health problems.*

Even when you already have health issues, Vitamin D can help in the treatment of most illnesses.*

Effects of Vitamin D

Almost every organ system in your body is influenced by Vitamin D.

Here's a summary: 

Myths about Vitamin D  

Unfortunately, there are a number of myths about Vitamin D.

Myths that I frequently hear that are incorrect:

Epidemic Of Vitamin D Deficiency

The fact is that most of us are low in Vitamin D.

At the Jamila Diabetes & Endocrine Medical Center, which is located in sunny Southern California, we routinely measure Vitamin D in our patients.

More than 90% of our patients are low in Vitamin D! Many of these patients drink milk and take a multivitamin as well as a calcium tablet that contains vitamin D.

So why is Vitamin D Deficiency so common?  

The sun is the main source of Vitamin D and accounts for 90% of Vitamin D in our body. Upon exposure to the sun, our skin manufactures Vitamin D, which then finds it's way into the blood stream. Cholesterol is the raw material for the synthesis of Vitamin D.  

Most of us don't get enough sun exposure. Often our jobs and lifestyle forces us to stay indoors. Even when we do go out in the sun, we make sure to put a healthy layer of sun-screen which blocks the synthesis of vitamin D in our skin. Even most makeup now contains sun-screen. 

Unfortunately, we're not told that the sun is beneficial as well. The truth is that the sun is both good and bad for us. It provides us with Vitamin D,  but may also zap us with an occasional skin cancer.     

How do I know If I am low in Vitamin D?  

Get your vitamin D level checked. It's a simple blood test. However, it's very important to get the correct test for Vitamin D.

There are two tests for vitamin D level:        

25 OH Vitamin D and 1,25 OH Vitamin D.  

25 OH Vitamin D (and NOT the 1,25 OH  Vitamin D) is the correct test for diagnosing Vitamin D deficiency.

Another common problem is the normal range provided by the lab that comes with the results. In my experience, most normal ranges provided by the lab are incorrect. A 25 OH vitamin D level less than 30 ng/ml (or 75 nmol/L) is considered low by most endocrinologists.    

What's the Treatment of Vitamin D Deficiency?  

Treatment of Vitamin D deficiency varies from person to person and must be individualized.

How much vitamin D to take?

It varies from person to person.* That's why Dr. Zaidi does not believe in "One-size-fits-all recommendation on vitamin D. He has developed a scientific strategy: Get your Vitamin D level checked and start vitamin D supplement, based on the table in his ground breaking book, "Power of Vitamin D."

As a general guideline, click here to learn how much vitamin D do you need.

What type of vitamin D? - D3 or D2?

Dr. Zaidi recommends vitamin D 3 as this is the type of vitamin D that we get from sun exposure, which is the main source of vitamin D. On the other hand, vitamin D2 is of plant origin and is only a minor source of vitamin D under normal physiological conditions. 

What route of absorption?

Dr. Zaidi recommends SUBLINGUAL route for absorption as compared to oral ingestion.

Why? Because sublingual absorption takes vitamin D directly into the systemic circulation as does vitamin D from skin. In contrast vitamin D from oral ingestion is absorbed into the portal circulation from the intestines, which takes it to the liver first before entering into the systemic circulation. In this way oral ingestion is not physiological and sublingual absorption is physiological.* This becomes even more important in people who have problems with digestion, take medications that can interfere with the intestinal absorption of vitamin D and people with stomach bypass surgery including those with lap-band procedures.*

photojafer Nutritional Products, in collaboration with Dr. Zaidi, now makes available a high quality Vitamin D3 formula for Sublingual absorption.

Each bottle of Sublingual Vitamin D3 contains 120 tablets.

Each tablet contains 5000 IU of Vitamin D3.


Regular Price = $29.95 per bottle

Sale Price = $19.95 per bottle




You can now make your secure purchase online using the PayPal shopping cart. It is not necessary to be a PayPal member, you can just use your credit card.

 Note: We do not ship outside the USA. Sorry for the inconvenience.


What is Vitamin D Toxicity?  

If you take too much Vitamin D, your serum calcium level may get elevated, which if mild usually does not cause any symptoms.

However, if serum calcium is too high, you may develop nausea, excessive urination, lethargy, heart problems, drowsiness and in extreme cases, even coma and death.

So it is important that you let your physician know about your vitamin D dose. Your physician should monitor your serum calcium level which is often included in a routine chemistry panel.

For details on Vitamin D, please refer to Dr. Zaidi's new book, "Power of Vitamin D."


Warnings – Disclaimer: This website is for educational purposes only. The information as well dietary supplements in this website are not intended to diagnose, treat, cure or prevent any disease. *These statements have not been evaluated by the Food and Drug Administration. Dietary supplements are Not intended for use by pregnant or nursing women. If you are taking any medications, planning any medical or surgical procedure or have any medical condition, consult your doctor before using any of the supplements. Discontinue use and consult your doctor if any adverse reactions occur. Keep out of reach of children. Do not use if outer wrap is missing or torn. Store at room temperature.



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