HoldsUp

Michael Grandner

Michael Grandner is a researcher in behavioral sleep medicine and sleep health. His published research investigates the relationships between sleep, circadian rhythms, cardiovascular health, and cognitive decline. Additionally, his work explores the social determinants of sleep disparities, insomnia chronicity, and interventions to improve sleep apnea treatment adherence.

107 claims checked on air: 9 context 2 contradicted 5 overstated 78 supported 13 unverified

What they said on air - overstated

3 citing their own research

2:16:05overstatedmoderateWhy You Can’t Sleep (and How to Fix It) | Dr. Michael Grand

Shift work is a known carcinogen and increases the risk of developing diabetes and dementia.

"shift work in general car- known carcinogenic. It increases diabetes risk, increases dementia risk. Like shift shift work isn't good." (said at 2:16:05)

The claim bundles three assertions. First, shift work is not classified as a 'known carcinogen' (IARC Group 1); rather, the International Agency for Research on Cancer (IARC) classified night shift work as 'probably carcinogenic to humans' (Group 2A) due to limited epidemiological evidence in humans alongside sufficient animal and mechanistic evidence. Second, large observational cohorts and meta-analyses support an increased risk of type 2 diabetes among shift workers (e.g., pooled hazard ratio ~1.30). Third, meta-analyses of observational studies demonstrate a modest but statistically significant positive association between shift work and the risk of dementia (pooled hazard ratio ~1.13). Because shift work is a probable rather than a confirmed/known carcinogen, the overall statement is overstated.

2:19:05overstatedmoderateWhy You Can’t Sleep (and How to Fix It) | Dr. Michael Grand

In sleep-deprived individuals, a daytime nap significantly improves metabolism and muscle strength.

"there's data that shows like even in sleep-deprived people, a decent nap in the middle of the day can dramatically improve metabolism, muscle strength, all this stuff." (said at 2:19:05)

A meta-analysis of randomized controlled trials (PMID: 36690376) indicates that a daytime nap (30 to <60 minutes) provides moderate-to-large improvements in physical and cognitive performance (standardized mean difference = 0.99 for physical performance) and reduces perceived fatigue following normal sleep or partial sleep deprivation in athletic and active cohorts. However, characterizing this as a 'dramatic' improvement in both muscle strength and systemic metabolism overstates the magnitude and scope of the evidence; napping primarily acts as an acute restorative countermeasure to temporary performance deficits rather than substantially altering underlying metabolic function.

3:33:02overstatedmoderateWhy You Can’t Sleep (and How to Fix It) | Dr. Michael Grand

Untreated sleep apnea is a leading cause of frequent nocturnal urination.

"Untreated sleep apnea is probably the leading cause of nocturnal frequent urination, because you keep having these arousals at night and your bladder is like, "Okay, while you're awake, might as well."" (said at 3:33:02)

Untreated obstructive sleep apnea (OSA) is a well-recognized, frequent contributor to nocturia (nocturnal frequent urination), and CPAP therapy often improves or resolves these symptoms. However, designating it as 'probably the leading cause' is overstated; nocturia is a multifactorial condition with several leading causes, including lower urinary tract dysfunction (such as benign prostatic hyperplasia and overactive bladder), cardiovascular disease, nocturnal polyuria from aging or diabetes, and diuretic use. Furthermore, the physiological driver in OSA is not merely waking up and deciding to void, but primarily inspiratory efforts against an occluded airway creating negative intrathoracic pressure, cardiac distension, and elevated release of atrial natriuretic peptide (ANP), which directly induces nocturnal polyuria.

5:07:50overstatedlowtheir own paperWhy You Can’t Sleep (and How to Fix It) | Dr. Michael Grand

A comprehensive literature review led by Teresa Arora found that improving sleep consistently leads to improvements in physical and emotional resilience across studies.

"A colleague of mine, Teresa Arora, she led this project that I also helped on. We looked at... We basically scoured the entire medical literature on resilience and sleep... And basically what we found was across the board, people... If you can sleep better, your resilience will improve." (said at 5:07:50)

A 2022 systematic review and meta-analysis led by Teresa Arora (PMID 35462348) examined the relationship between sleep duration/quality and resilience across 68 studies in non-clinical populations. The meta-analysis identified a weak positive correlation between sleep duration and resilience (r = 0.11) and a modest correlation with sleep quality (r = 0.27; attenuated to r = 0.18 in prospective studies), alongside evidence of significant publication bias. The authors noted that the literature is predominantly observational and cross-sectional, concluding that additional prospective and interventional research is needed to verify whether improving sleep directly improves resilience.

5:27:19overstatedlowWhy You Can’t Sleep (and How to Fix It) | Dr. Michael Grand

Sleeping with a pet or other animal in the bedroom increases sleep fragmentation.

"Anyone who has an animal in their room, another mammal in their room moving around... You're going to have more fragmented sleep." (said at 5:27:19)

While objective actigraphy studies confirm that an animal's nighttime movements can trigger awakenings or movement transitions in humans—particularly when sharing the same bed—the claim that having an animal anywhere in the room universally fragments sleep is overstated. An actigraphy study of 40 adults found that having a single dog in the bedroom did not significantly impair sleep efficiency, whereas having the dog directly on the bed did reduce sleep efficiency. Other observational studies show that while bed-sharing and owning multiple pets are associated with poorer objective sleep parameters and subjective sleep quality, having a pet simply present in the bedroom does not consistently cause sleep disruption.

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