HoldsUp

Paul Saladino MD · 2023-08-22 · Paul Saladino (host)

Is hair loss reversible?

27 claims checked against research: 4 overstated 2 needing context 18 supported 3 unverified

4

Overstated

0:12:49Paul Saladino (host)overstatedvery low

Taurine supplementation improves longevity in animal models including worms, mice, and primates.

"Along the same vein, there's evidence that taurine, a nutrient that I've been enamored with recently, which has been studied across multiple species and improves longevity in worm models, in mice, and in primates" (said at 0:12:49)

The claim is overstated regarding primates. A landmark 2023 study by Singh and colleagues demonstrated that taurine supplementation significantly extended median lifespan (longevity) by 10% to 12% in mice and increased lifespan in worms (C. elegans) and yeast. However, in middle-aged rhesus monkeys, the study only assessed healthspan parameters over a 6-month period (finding improvements in bone density, body fat, fasting glucose, liver health, and immune markers); it did not test or demonstrate an increase in primate lifespan or longevity.

0:14:43Paul Saladino (host)overstatedmoderate

Phytic acid found in legumes and whole grains binds to divalent cations including zinc, copper, magnesium, and selenium, inhibiting their absorption.

"they also contain phytates that can bind to the mineral, lowering its absorption. So when I talk about phytates, which is essentially phytic acid in things like oats, people always criticize me and say this isn't a big deal. But they do, and they have been shown repeatedly to prevent the absorption of zinc and other minerals, all of the divalent cations. And in fact, all of these minerals studied in the studies that I'll show you in a moment—zinc, copper, magnesium, selenium—these are all divalent cations, can be bound by phytic acid found in legumes and whole grains, and their absorption can be prevented." (said at 0:14:43)

The speaker claims that phytic acid in legumes and whole grains binds to all divalent cations, specifically zinc, copper, magnesium, and selenium, inhibiting their absorption. While phytic acid (myo-inositol hexakisphosphate) is well-established to chelate polyvalent cations and inhibit the intestinal absorption of zinc, iron, calcium, and magnesium, its interaction with selenium and copper differs from the blanket statement made: 1. **Zinc and Magnesium**: Human and animal literature strongly supports that phytate inhibits zinc and magnesium absorption. For example, a controlled stable-isotope study in humans (PMID 8829129) demonstrated that a high-fibre, high-phytate diet significantly lowered fractional absorption and resulted in negative balances for zinc, copper, and magnesium. Reviews also confirm phytic acid as a major dietary inhibitor of zinc absorption (PMID 10801947). 2. **Copper**: Human studies show that while phytate affects zinc and iron, its effect on copper absorption is far weaker or non-existent in typical human diets. Review evidence specifically notes that phytic acid inhibits the absorption of iron, zinc, calcium, and manganese in adults, but *not* copper (PMID 12949395). 3. **Selenium**: Selenium in foods is predominantly absorbed in organic forms (such as selenomethionine) or inorganic oxyanions (selenite/selenate), not as a free divalent metallic cation bound by phytate. In animal studies, dietary phytate actually increased tissue selenium concentrations and glutathione peroxidase activity, showing a positive relationship with selenium status rather than inhibiting its absorption (PMID 7719737). Because phytic acid inhibits zinc and magnesium absorption but does not inhibit copper or selenium absorption in the same manner, broad assertions sweeping all four minerals together overstate the scientific consensus.

0:24:35Paul Saladino (host)overstatedvery low

Deficiencies in iron, vitamin D, folate, vitamin B12, and selenium are linked to premature hair graying or whitening in childhood or early adulthood, and supplementation can improve it.

"Iron, vitamin D, folate, B12, and selenium are vitamins and minerals that may be involved in hair graying or whitening during childhood or early adulthood. Supplementing these deficiencies can improve premature graying." (said at 0:24:35)

Observational case-control studies in adolescents and young adults have identified associations between premature hair graying (canities) and lower serum levels of certain micronutrients, notably ferritin (iron stores) and vitamin B12, as well as vitamin D and calcium. However, the evidence is observational and cross-sectional. There are no robust randomized controlled trials demonstrating that supplementing these vitamins or minerals effectively reverses or improves premature hair graying, making the therapeutic claim overstated.

0:12:51Paul Saladino (host)overstatedvery low

Deficiencies in taurine or taurine supplementation are linked with hair loss and hair growth.

"Well, taurine supplementation or deficiencies in taurine are linked with hair loss." (said at 0:12:51)

Evidence linking taurine to hair biology comes primarily from in vitro laboratory studies and animal models, alongside multi-ingredient dietary supplement trials. In vitro studies on isolated human hair follicles demonstrate that taurine is taken up by the follicle, enhances survival, and protects against TGF-beta1-induced growth inhibition and fibrosis. Additionally, preclinical animal models of alopecia indicate that topical or targeted taurine formulations can mitigate perifollicular oxidative stress and stimulate regrowth. However, there is no robust clinical evidence demonstrating that dietary taurine deficiency directly causes hair loss in humans or that standalone oral taurine supplementation is an established monotherapy for alopecia.

Unverified means no publication matching the claim was located; it does not prove the claim false. Spotted an error? See the corrections policy - disputes from the people quoted are prioritized.