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Thorne Research, Riboflavin 5' Phosphate, 60 Veggie Caps

By Thorne Research

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  • Product Code: THR-11502
  • UPC Code: 693749115021
  • Package Quantity: 60 Veggie Caps
  • Dimensions: 3 x 1.7 x 1.7 in, 0.05 lbs (0.02 kg)
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Save $2.00 when you purchase these items today for only $28.55


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Product Overview

  • Dietary Supplement
  • The Bioactive form of Riboflavin
  • The Active form of Vitamin B2 more Readily Used by the Body
  • Riboflavin 5'-Phosphate is Yeast Free

Riboflavin, also known as vitamin B2, plays a key role in the activation and conversion of other B vitamins. For instance, it is necessary for activation of vitamin B6, conversion of tryptophan to niacin, and conversion of folate to its various active forms. Riboflavin also plays a crucial role in fat and glucose metabolism, red blood cell synthesis, and the production and regulation of certain hormones.

As with many B vitamins, riboflavin must be converted to its active form – riboflavin 5'-phospate (R5P) – in order for it to be utilized by the body. Because absorption of riboflavin occurs in the upper GI tract, a compromised digestive system can adversely affect the body's ability to convert riboflavin to R5P. In addition, certain prescription medications can interfere with the proper absorption of riboflavin and deplete the body of its stores.

Suggested Use

Take 1 capsule one to three times daily or as recommended by your health-care practitioner.

Other Ingredients

Microcrystalline cellulose, hypromellose (derived from cellulose) capsule, silicon dioxide.


Tamper Evident: Use only if bottle is sealed.

If pregnant, consult your health-care practitioner before using this product.

Store tightly sealed in a cool, dry place.

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Supplement Facts
Serving Size: One Capsule
  Each Capsule Contains: % DV
Riboflavin (as Riboflavin 5' - Phosphate Sodium) 36.5 mg 2,147%
Daily Value (DV)

iHerb Customer Reviews

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Quality and Purity I Trust

Posted by Reviewer2025838 on Dec 18, 2011

I love the Thorne brand and thought I'd try these. I've been cycling different B vitamins to see if any had an effect on my sleep, mood and memory. The one that actually helps is Vitamin B1 (Thiamine) which my research shows is easily blocked if you consume tea or red wine with meals (both contain tannins which block B1 absorption).

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7 people found the following review helpful

thorn r-5-p

Posted by Reviewer2520330 on Apr 29, 2010

i believe that coenymated vitamins are more active than the usual ones, but i think this product would have to be used sublingually (dissolved under tongue), ive read the body will digest the coenzymation from it otherwise, and in my experience i think that is true, since this product had a diuretic effect on me, and ive read that is what happen when the b's arent used and are immediately flushed. ive opted for another coenzymated b complex that is sublingual and ive noticed things no other b complex has been able to do, such as increased body heat (imroved basal metabolic rate) and energy.

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10 people found the following review helpful

Thorne Research's Riboflavin 5 Phoshate

Posted by Reviewer2559753 on Feb 04, 2011

This is a difficult product to find in veggie caps. So I was very pleased to find iHerb had it. And both me and my husband have so much more energy when taking this extra Riboflavin in addition to our multiple vitamin. Yes, I would recommend taking this product in addition to a regular multiple vitamin fomula. In Florida

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2 people found the following review helpful

Active Form & Effective - Vitamin B6

Posted by Reviewer2648337 on Feb 17, 2014

easy to take in one capsule - active co-enzymed form of vitamin B6.

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2 people found the following review helpful

Active form

Posted by Reviewer2733085 on Jul 25, 2011

I like using the active forms of B vitamins, like this form of B2 rather than forms that are cheap, but not found naturally. This one is priced reasonably too, and I trust Thorne to make quality products.

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1 person found the following review helpful

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