Pierre Capel
Utrecht University
Pierre Capel is a professor emeritus of experimental immunology at Utrecht University in the Netherlands. His academic research has covered topics ranging from genetic modification to cancer immunotherapy. Additionally, he has collaborated with Wim Hof to study the scientific mechanisms behind extreme cold exposure and physical feats.
21 claims checked on air: 2 context 3 contradicted 3 overstated 11 supported 2 unverified 6 flagged
What they said on air - contradicted
Complete lack of sleep causes death within seven days.
"Without sleep, seven days you die." (said at 0:07:06)
There is no evidence that complete lack of sleep causes death within seven days in humans. In experimental animal models of total sleep deprivation (such as Rechtschaffen's disc-over-water studies in rats), fatal outcomes or states requiring imminent sacrifice occurred after 11 to 32 days of continuous deprivation, not within seven days. Furthermore, documented human case observations of extended voluntary wakefulness (up to 11 days or 264 hours) have produced severe cognitive impairment, perceptual disturbances, and metabolic strain, but not death.
- contradicts: Sleep deprivation in the rat: X. Integration and discussion of the findings. (Sleep 1989)
"These studies showed that total sleep deprivation, paradoxical sleep deprivation, and disruption and/or deprivation of non-rapid eye movement (NREM) sleep produced a reliable syndrome that included death, debilitated appearance, skin lesions, increased food intake, weight loss, increased energy expenditure, decreased body temperature during the late stages of deprivation, increased plasma norepinephrine, and decreased plasma thyroxine." (abstract, results, passage verified)
pubmed - contradicts: Sleep deprivation in the rat: III. Total sleep deprivation. (Sleep 1989) · cited 342x in the literature
"All TSD rats died or were sacrificed when death seemed imminent within 11-32 days." (abstract, results, passage verified)
pubmedfull study (doi)
At a blood pH of 7.7, pain receptors dissociate into monomeric forms, preventing the trimerized active signaling state and eliminating pain and anxiety signaling in the spinal cord and amygdala.
"And at pH 7.7 the pain receptor is a monomer, so it's out, so no pain. But the same receptor is also in the amygdala giving fear and pain, but also in the spinal cord and all over your body. So all of the sudden you don't feel pain, don't feel anxiety" (said at 0:48:28)
The claim that pain receptors dissociate into inactive monomers at an alkaline blood pH of 7.7 to eliminate pain and anxiety contradicts structural and biophysical evidence on proton-sensitive receptors. Acid-sensing ion channels (ASICs), which mediate proton-activated signaling in nociceptive pathways and fear/anxiety circuits in the amygdala, assemble as stable, chalice-shaped trimers embedded in the membrane. Gating is mediated by proton binding to acidic residues and carboxyl-carboxylate pairs that drive conformational changes within the intact trimeric complex to open or close the pore, not by dissociation into monomers. Furthermore, severe systemic alkalosis (pH 7.7) is a life-threatening medical emergency and does not eliminate pain or anxiety signaling through receptor monomerization.
- contradicts: Structure of acid-sensing ion channel 1 at 1.9 A resolution and low pH. (Nature 2007) · cited 1072x in the literature
"Acid-sensing ion channels (ASICs) are voltage-independent, proton-activated receptors that belong to the epithelial sodium channel/degenerin family of ion channels and are implicated in perception of pain, ischaemic stroke, mechanosensation, learning and memory... Each subunit of the chalice-shaped homotrimer is composed of short amino and carboxy termini, two transmembrane helices, a bound chloride ion and a disulphide-rich, multidomain extracellular region enriched in acidic residues and carboxyl-carboxylate pairs within 3 A, suggesting that at least one carboxyl group bears a proton... Between the acidic residues and the transmembrane pore lies a disulphide-rich 'thumb' domain poised to couple the binding of protons to the opening of the ion channel, thus demonstrating that proton activation involves long-range conformational changes." (abstract, results, passage verified)
pubmedfull study (doi)
Human mate selection and attraction are influenced by olfactory perception of highly polymorphic Major Histocompatibility Complex (MHC/HLA) peptide fragments secreted in body fluids and sweat.
"these vital molecules which are different in each individual are being chopped up in little peptides and secreted by all type of body fluids which uh are in the armpits and between the legs and in all the sexual organs and sweat. There they are secreted. uh and as soon as you smell them you know how the immune system of the other person is and so therefore you come into the area that smell is an important thing for a genetic selection with whom you have to mate" (said at 1:06:15)
While early small studies such as Wedekind et al. (1995) suggested that humans prefer the scent of MHC-dissimilar individuals, subsequent research and comprehensive meta-analyses contradict the claim that MHC peptide olfaction reliably drives human mate selection. A 2020 meta-analysis synthesizing genomic mate selection, relationship satisfaction, and body odour preference studies found no statistically significant association between MHC dissimilarity and body odour preferences, nor any overall significant effect on actual human mate choice.
- contradicts: Major histocompatibility complex-associated odour preferences and human mate choice: near … (Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2020) · cited 66x in the literature
"Analysis of genomic studies reveals no association between MHC-dissimilarity and mate choice in actual couples; however, MHC effects appear to be independent of the genomic background. The effect of MHC-dissimilarity on relationship satisfaction was not significant, and we found evidence for publication bias in studies on this area. There was also no significant association between MHC-dissimilarity and odour preferences. Finally, combining effect sizes from all genomic, relationship satisfaction, odour preference and previous mate choice studies into an overall estimate showed no overall significant effect of MHC-similarity on human mate selection." (abstract, results, passage verified)
pubmedfull study (doi) - supports: MHC-dependent mate preferences in humans. (Proceedings. Biological sciences 1995) · cited 965x in the literature
"Female and male students were typed for their HLA-A, -B and -DR. Each male student wore a T-shirt for two consecutive nights. The next day, each female student was asked to rate the odours of six T-shirts. They scored male body odours as more pleasant when they differed from the men in their MHC than when they were more similar." (abstract, results and conclusions, passage verified)
pubmedfull study (doi)
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