HoldsUp

Dale Bredesen

Dale Bredesen is a researcher whose work focuses on cognitive decline and Alzheimer's disease. His published research investigates precision medicine and multi-factorial interventions, including dietary protocols such as the KetoFLEX 12/3 diet and personalized therapeutic programs. Additionally, his studies explore molecular mechanisms, metabolic pathways, and targeted pharmacological agents for Alzheimer's disease.

31 claims checked on air: 3 context 1 contradicted 4 overstated 19 supported 4 unverified

What they said on air - supported

2 citing their own research

0:11:08supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Approximately 75 million Americans have a single copy of APOE4, and 7 million Americans have two copies of APOE4.

"75 million Americans have a single copy; 7 million Americans have two copies." (said at 0:11:08)

Epidemiological and population genetics studies in the United States establish that approximately 20% to 25% of the US population carries a single APOE ε4 allele (heterozygotes), and approximately 2% carries two copies (homozygotes). Applied to the total US population (roughly 335 million), 20% to 25% corresponds to approximately 67 to 84 million Americans with a single copy of APOE4, and ~2% corresponds to approximately 6.7 to 7 million Americans with two copies (APOE4/4). The guest's figures of 75 million single-copy carriers and 7 million homozygotes align closely with standard epidemiological estimates.

0:16:06supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Beta-amyloid, phosphorylated tau, and alpha-synuclein are antimicrobial peptides.

"there's no question amyloid is part of the response. It is an antimicrobial peptide. And guess what? p-tau is also antimicrobial. Guess what? Alpha-synuclein of Parkinson's and Lewy body and MSA, that's also antimicrobial." (said at 0:16:06)

The speaker's statement accurately reflects published research demonstrating that amyloid-beta, phosphorylated tau, and alpha-synuclein exhibit antimicrobial activity and act as effector molecules of the innate immune system. In vitro and animal models have identified antimicrobial peptide (AMP) characteristics for amyloid-beta (entrapping bacteria and viruses), phosphorylated tau (neutralizing herpes simplex virus 1), and alpha-synuclein (restricting viral and bacterial replication and modulating immune responses).

0:23:26supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Phosphorylation of the tau protein alters its charge and conformation, causing it to dissociate from microtubules and leading to neurite collapse.

"This same molecule, when you now have insults and you're now switching to protection mode, becomes phosphorylated, which changes its charge and changes its shape. It pops off the microtubules, which now allows the neurites to collapse" (said at 0:23:26)

Biophysical and computational modeling studies demonstrate that phosphorylation of the tau protein introduces negative electrostatic charges and induces distinct conformational changes. These changes alter the microtubule-binding region, reducing tau's affinity for tubulin and promoting its dissociation from microtubules, which destabilizes the neuronal cytoskeleton and contributes to neurite retraction and collapse.

0:24:10supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Blood levels of phosphorylated tau, specifically p-tau217, strongly correlate with brain amyloid burden and ongoing neuropathology.

"And the striking relationship between phospho-tau levels in the blood—specifically p-tau217 in the blood—and the amount of amyloid in the brain and ongoing pathology in the brain." (said at 0:24:10)

Large prospective cohort and diagnostic validation studies demonstrate that blood levels of tau phosphorylated at threonine 217 (plasma p-tau217 and %p-tau217) correlate strongly with brain amyloid-beta deposition (measured by amyloid PET) and neurofibrillary tau tangles (measured by tau PET or postmortem neuropathological examination). In multiple validation cohorts, plasma p-tau217 differentiates neuropathologically confirmed Alzheimer's disease and amyloid PET positivity with very high diagnostic accuracy (AUCs ranging from 0.89 to 0.97).

0:25:09supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Glial fibrillary acidic protein (GFAP) is an intermediate filament protein whose levels in blood elevate during reactive astrogliosis and brain inflammation.

"And that is glial fibrillary acidic protein that is an intermediate filament protein. So what happens when your astrocytes that are supporting your neurons now balloon up and start to react because you're in inflammation mode or because you are trying to do some rebuilding, they essentially, like the Hulk, they boom, they hyperactivate. And when they do that, they are building with GFAP, so they've got to have that as a protein that now goes up. You can again pick that up in the blood." (said at 0:25:09)

Glial fibrillary acidic protein (GFAP) is a type III intermediate filament protein predominantly expressed in astrocytes. During reactive astrogliosis triggered by central nervous system injury, inflammation, or neurodegeneration, astrocytes upregulate GFAP expression, and GFAP is subsequently released into biofluids (including blood/plasma/serum), where it serves as a well-established biomarker of astrocyte activation.

0:26:12supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

A biomarker profile of normal p-tau, normal GFAP, and elevated neurofilament light (NfL) in blood is commonly associated with frontotemporal dementia.

"for example, if you've got a normal p-tau, a normal GFAP, but a high NfL, the first concern is frontotemporal dementia. That is a common one to give you that pattern." (said at 0:26:12)

Blood-based biomarker profiling demonstrates that the combination of normal phosphorylated tau (p-tau), normal glial fibrillary acidic protein (GFAP), and elevated neurofilament light chain (NfL) is characteristic of frontotemporal dementia (FTD). In clinical differential diagnosis panels, elevated p-tau and GFAP are hallmarks of Alzheimer's disease pathology (amyloid- and tau-related astrogliosis and phosphorylation), whereas FTD typically exhibits non-elevated p-tau and GFAP alongside marked neuroaxonal injury reflected by elevated plasma NfL.

0:35:10supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Poor glucose utilization in the temporal and parietal regions on PET scan is a hallmark of Alzheimer's disease.

"And when you look at a PET scan, that's what you see, poor glucose utilization in the temporal and parietal region. That's the hallmark of Alzheimer's disease." (said at 0:35:10)

Positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) measures regional cerebral glucose metabolism. A distinct pattern of reduced glucose utilization (hypometabolism) in the temporoparietal regions of the brain is an established diagnostic hallmark of typical Alzheimer's disease.

0:35:45supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Research by Mary Newport and Stephen Cunnane demonstrates that exogenous ketones are beneficial for individuals with mild cognitive impairment.

"So at the beginning, we just give exogenous ketones, and as people like Mary Newport and Stephen Cunnane have shown, that is helpful for people even with MCI." (said at 0:35:45)

Published clinical research by Stephen Cunnane and colleagues, as well as work by Mary Newport, supports the claim that exogenous ketogenic supplementation can benefit brain energetics and cognitive function in cognitive impairment and mild cognitive impairment (MCI). In a 6-month randomized controlled trial led by Cunnane's team (Fortier et al., 2021), a ketogenic medium-chain triglyceride (kMCT) drink significantly improved memory recall, verbal fluency, naming, and executive processing speed in individuals with MCI compared to placebo. Newport and colleagues previously reported case-based clinical and functional improvements following administration of a ketone monoester in Alzheimer's disease.

0:36:10supportedlowHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Culturing primary brain cells in vitro requires insulin in the growth medium for neuronal survival.

"When, you know, when we used to grow brain cells in a dish in the lab, which we did for years and years, you had to always include insulin in their medium or they wouldn't survive. Insulin is such a crucial trophic factor for neurons." (said at 0:36:10)

Primary neuronal culture protocols (such as those using defined serum-free supplements like B-27 or N-2) universally require insulin or related trophic factors (such as IGF-1) to support long-term neuronal survival and metabolic support in vitro. Without insulin or cross-reacting insulin-family trophic factors in serum-free defined media, cultured primary neurons rapidly undergo apoptotic cell death.

0:41:55supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Clinical trials show that magnesium L-threonate supplementation improves cognitive outcomes.

"I happen to like uh magnesium L-threonate for many people. Um, that and that one of the reasons I like that is because it's actually had trials, um things where there are data to actually show, yes, people did better with magnesium L-threonate." (said at 0:41:55)

Randomized, double-blind, placebo-controlled clinical trials support the claim that magnesium L-threonate supplementation improves cognitive outcomes. A 2016 trial (n=44) in adults aged 50–70 with cognitive impairment found significant improvements in overall cognitive ability and executive function with a magnesium L-threonate formulation compared to placebo. Subsequent randomized trials have shown similar benefits: a 2022 trial (n=109) reported significant improvements in memory quotient scores on the Clinical Memory Test in healthy adults, and a 2025 trial (n=100) demonstrated improvements in overall cognitive performance on the NIH Total Cognition Composite, working memory, and reaction time in adults aged 18–45. The overall evidence base is moderate in certainty due to relatively small sample sizes across individual trials.

0:51:15supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Head-to-head clinical comparisons show that GLP-1 receptor agonists outperform Januvia (sitagliptin).

"Of course now they've gone head-to-head Januvia with GLP-1, and the GLP-1s outperform Januvia." (said at 0:51:15)

A systematic review and meta-analysis of head-to-head randomized controlled trials confirms that GLP-1 receptor agonists are significantly more effective than sitagliptin (Januvia) in lowering glycated hemoglobin (HbA1c) and reducing body weight in adults with type 2 diabetes.

0:52:00supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

A clinical trial evaluating intranasal insulin for Alzheimer's disease or cognitive decline failed to meet its primary efficacy endpoints.

"This is the same thing as, you know, several years ago there was a trial where they tried intranasal insulin. It sounded so good: 'Let's get insulin into the brain.' Well, the problem is you may be creating—and that trial failed unfortunately" (said at 0:52:00)

A major multi-site Phase 2/3 randomized controlled trial (the SNIFF trial, NCT01767909) evaluating intranasal insulin (40 IU daily) versus placebo over 12 months in 289 adults with mild cognitive impairment or Alzheimer disease dementia failed to meet its primary efficacy endpoint. In the primary intention-to-treat analysis (n = 240), there was no statistically significant difference between intranasal insulin and placebo on the primary outcome, the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog-12; difference 0.0258 points; 95% CI, -1.771 to 1.822; P = .98), nor were there differences in secondary clinical or cerebrospinal fluid outcomes.

0:52:55supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Amyloid-beta disrupts insulin signaling by interfering with the insulin receptor and its substrate IRS-1.

"If you look at the insulin receptor and then its interaction with IRS-1, its major signaling molecule, guess what interferes with that insulin signaling? Amyloid." (said at 0:52:55)

Preclinical models and human brain tissue studies demonstrate that amyloid-beta (Aβ) oligomers disrupt neuronal insulin signaling by triggering stress kinases such as JNK, which induces inhibitory serine phosphorylation of insulin receptor substrate-1 (IRS-1) and blocks normal insulin signaling downstream of the insulin receptor.

0:54:58supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Metformin activates AMPK by inhibiting ATP production through the mitochondrial respiratory chain.

"The way it triggers your kinase is by preventing you from making the ATP that would normally inhibit that. So what you're really doing is you're saying, 'Okay, you're eating, you're trying to do everything to get more energetics, but I'm going to block that so that you'll have more AMP and you'll now activate your AMP kinase.'" (said at 0:54:58)

The speaker's description matches the widely recognized canonical mechanism of metformin. Metformin inhibits Complex I (NADH:ubiquinone oxidoreductase) of the mitochondrial respiratory chain, reducing cellular ATP synthesis and thereby increasing the cellular AMP:ATP (and ADP:ATP) ratio, which promotes the allosteric activation and phosphorylation of AMP-activated protein kinase (AMPK).

0:58:00supportedhighHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Amyotrophic lateral sclerosis (ALS) occurs more frequently in men than in women.

"We've got men getting more ALS and men getting more Parkinson's." (said at 0:58:00)

Epidemiological evidence consistently demonstrates that amyotrophic lateral sclerosis (ALS) has a higher incidence in men than in women. A systematic review and meta-analysis of 39 population-based studies found a pooled male-to-female standardized incidence ratio of 1.35 (95% CI 1.31–1.40), confirming a higher risk in men across age groups.

0:59:33supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Exposure to organic toxicants such as trichloroethylene (TCE), perchloroethylene (PCE), dieldrin, and paraquat contributes to the risk and pathology of Parkinson's disease.

"I would mention, as you know, the common things that are driving this in that particular network are the organic toxicants. You mentioned MPP+, MPTP, but it's the things like trichloroethylene and perchloroethylene and dieldrin and paraquat" (said at 0:59:33)

Extensive epidemiological and mechanistic literature supports the link between exposure to organic toxicants—including industrial solvents like trichloroethylene (TCE) and perchloroethylene (PCE), as well as pesticides like paraquat and dieldrin—and an increased risk and hallmark pathology of Parkinson's disease. These agents trigger neurotoxic pathways including mitochondrial complex I inhibition, oxidative stress, neuroinflammation, and selective dopaminergic neuron degeneration in the substantia nigra.

1:01:07supportedvery lowHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Estradiol binding to its receptor upregulates alpha-secretase, which cleaves APP to promote non-amyloidogenic processing.

"estradiol binds to its receptor, enters the nucleus, of course affects hundreds of genes. One of the things that it turns up is the alpha-secretase that cleaves the APP to give you the connection, to give you that supportive side." (said at 1:01:07)

Preclinical in vitro and rodent studies support the mechanism described by the speaker. 17β-estradiol acting through estrogen receptors promotes the non-amyloidogenic pathway of amyloid precursor protein (APP) processing by upregulating α-secretase activity (specifically ADAM10), increasing neuroprotective soluble APPα (sAPPα) and decreasing amyloid-beta (Aβ42) accumulation. Because the evidence is derived primarily from animal and cellular models, the GRADE certainty is very low.

1:06:17supportedvery lowtheir own paperHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Expressing human Alzheimer's genes in Drosophila fruit flies generated an ADHD-like phenotype with hyperactivity that responded to dextroamphetamine.

"When we put human Alzheimer genes into fruit flies, guess what? They didn't get Alzheimer's, they got ADHD. And this is published. They fit all criteria. They were more in males. It was treated by the same drugs like dextroamphetamine beautifully. They had increased movement all the time." (said at 1:06:17)

A 2015 study published in the Journal of Neurology & Neurophysiology reported that an invertebrate Drosophila melanogaster Alzheimer's model exhibited features analogous to attention deficit hyperactivity disorder (ADHD), including hyperactivity, male predominance, and a reversible response to dextroamphetamine. Because the evidence is derived solely from an animal (invertebrate) model in a single preliminary report, the certainty of evidence for human clinical implications is very low.

1:06:37supportedmoderateHow to Make Your Brain Ageless: Prevent Cognitive Decline &

Published scientific research demonstrates a relationship between ADHD and an increased risk of cognitive decline.

"And there's more and more work, as you know, published about the relationship between ADHD and cognitive decline." (said at 1:06:37)

Published systematic reviews and observational cohort studies demonstrate a significant association between attention-deficit/hyperactivity disorder (ADHD) and an increased risk of subsequent cognitive decline and dementia. A meta-analysis of cohort and case-control studies found that individuals with ADHD had a significantly elevated hazard of developing all-cause dementia (pooled HR 2.52, 95% CI 1.51–4.22). While observational data show a clear link, researchers note that additional prospective studies are required to determine the exact direct causal mechanisms.

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