Phenol red may hurt children's ability to grow taller

This site lists high phenol red containing foods(well all high phenol foods of which phenol red is a subset).  The food list includes many foods of which would be almost impossible to avoid all of them.  If you replace milk with colostrum that will take phenol red levels down a little.


Phenol Red Inhibits Chondrogenic Differentiation and Affects Osteogenic Differentiation of Human Mesenchymal Stem Cells in Vitro.

"The purpose with this study was to investigate the effect of phenol red (PR) on chondrogenic and osteogenic differentiation of human mesenchymal stem cells (hMSCs). hMSCs were differentiated into chondrogenic and osteogenic directions in DMEM with and without PR for 2, 7, 14, 21, and 28 days. Gene expression of chondrogenic and osteogenic markers were analyzed by RT-qPCR. The presence of proteoglycans was visualized histologically. Osteogenic matrix deposition and mineralization were examined measuring the alkaline phophatase activity and calcium deposition. During chondrogenic differentiation PR decreased sox9, collagen type 2, aggrecan on day 14 and 21 (P < 0.05), and proteoglycan synthesis on day 21 and 28. Collagen type 10 was decreased on day 21 (P < 0.05). During osteogenic differentiation PR increased alkaline phosphatase on day 7 while decreased on day 21 (P < 0.05). PR increased collagen type 1 on day 7, 14, and day 21 (P < 0.05). The alkaline phosphatase activity was increased after 2, 7, and 14 days (P < 0.05). The deposition of calcium was decreased on day 21 (P < 0.05)."

Now this doesn't necessarily mean that phenol red decreases height as Sox9 and extracellular matrix components decrease during the hypertrophic and ossification stage and phenol red may be accelerating endochondral ossification while not affecting adult height.  However Col10 a hypertrophic stage marker decreases and proteoglycan synthesis decreases as well indicating that phenol red may actually decrease adult height rather than just accelerating it.  However, we can't say for sure without a longitudinal study with phenol red supplementation versus control.

b and e have phenol red whereas c and f do not and you can see the size difference.  Although it's possible that phenol red just slows down growth and eventually phenol red treated chondrocytes grow to normal levels.

"Chondrogenesis was induced in pellet cultures in polypropylene tubes, 2.5 × 105 cells/pellet, by addition of 100 nM Dexamethasone, 50 μg/ml L-Ascorbic Acid-2 phosphate, 40 μg/ml L-Proline, 1 mM sodium pyruvate, 1:100 ITS™+premix, and 10 ng/ml TGFβ3"

It's also possible that the effects of phenol red were specific to this medium and in the human body or with different medium phenol red would have no catabolic or even an anabolic effect.  Phenol red has estrogen dependent and independent effects.

"Bone marrow derived human hMSCs, male donor, 22 years, 7.39 population doublings (PDs) were seeded with 6.000 cells/cm2 in Mesenchymal Stem Cell Growth Medium "<-It's also possible that results would be different with a different donor.

Specific dosages of phenol red were not mentioned so we don't know how much phenol red is needed to take effect.  In the medium there is no where for phenol red to go but in the body it can be removed so that is another consideration.  But phenol red is still worth looking into.