About the Author: Broc Trammell is the Co-Founder and CEO of Thumos, a science-backed brain and gut health supplement company. A former Naval Special Warfare Operator and SWCC, Broc built Thumos alongside a fellow veteran after experiencing firsthand the cognitive toll of high-intensity military service. He is currently pursuing his MBA at the Wharton School at the University of Pennsylvania.
More than three-quarters of U.S. adults over the age of 40 expect to experience cognitive decline as they age, and roughly half believe it is at least somewhat likely they will develop dementia (AARP, 2025). The fear is real and growing. But what the data also reveals is something far more important: up to 45 percent of dementia cases are attributable to modifiable lifestyle and environmental factors (Alzheimer's Association, 2026). Nearly half of all cases of cognitive decline may be preventable through the choices people make every single day.
The problem is that most people are making those choices without understanding what actually drives brain health, and in doing so, they are making three critical mistakes that accelerate the very cognitive decline they fear. This blog breaks down each one, backed by the latest peer-reviewed research, and outlines what it takes to genuinely protect your cognitive function, mental clarity, and long-term brain longevity.
Mistake #1: Treating Sleep as Optional
If there is one non-negotiable pillar of brain health that the majority of high performers still sacrifice without a second thought, it is sleep. And the research on what happens when they do is damning.
A 2025 prospective study published in Bioinformation tracked 140 middle-aged adults between the ages of 40 and 60 over a three-year period using standardized cognitive batteries and sleep tracking devices. The results were unambiguous: individuals who slept fewer than six hours per night showed significantly greater declines in memory, executive function, and attention compared to those who maintained adequate sleep duration. Critically, these associations remained significant even after controlling for confounders including age, sex, body mass index, education level, depression, hypertension, and diabetes. The independent role of sleep in neurocognitive deterioration is not a hypothesis. It is documented (Biswas et al., 2025).
A separate 2025 study published in Cureus examining 300 participants aged 18 to 30 found that participants with shorter sleep durations scored significantly higher on measures of cognitive failure and perceived stress, with associations confirmed across multiple validated instruments including the Pittsburgh Sleep Quality Index and the Mini-Mental State Examination (Younas et al., 2025). The research makes clear that sleep deprivation is not just a problem for middle-aged adults. It is eroding cognitive performance across every age group.
The biological mechanism explains why. Sleep is when the brain performs its most critical maintenance work: synaptic pruning, memory consolidation, and clearance of neurotoxic waste through the glymphatic system. When sleep is cut short, these restorative processes are interrupted. Over time, the accumulation of neurotoxic waste and the failure of synaptic consolidation create the neurological conditions associated with accelerated cognitive decline and elevated dementia risk.
A 2025 scoping review published in Frontiers in Neuroscience confirmed that prolonged sleep deprivation severely impacts the brain's cognitive functions, ultimately leading to a deterioration in cognitive flexibility, with five independent studies involving total sleep deprivation all showing a highly consistent trend toward significant decline (Sun et al., 2025).
The fix is not complicated, but it requires treating sleep as the highest-priority brain health investment it actually is. Seven to nine hours of consistent, quality sleep is not a luxury. It is the biological foundation on which every other cognitive health strategy is built.
Mistake #2: Sitting Still and Calling It Rest
The second mistake is one that has become embedded in modern life so completely that most people do not recognize it as a mistake at all: prolonged sitting. The research on sedentary behavior and brain health is now expansive, and its findings are striking.
A 2025 study published in Alzheimer's and Dementia: The Journal of the Alzheimer's Association, led by researchers from the University of Pittsburgh and Vanderbilt University Medical Center, found that increased sedentary behavior among aging adults was associated with worse cognition and measurable brain shrinkage in areas directly linked to Alzheimer's disease risk. The effect was present regardless of how much exercise participants reported doing (University of Pittsburgh, 2025). Let that land: sitting for extended periods damages the brain even in people who exercise daily.
A 2025 systematic review published in Frontiers in Aging Neuroscience synthesizing the available research on sedentary behavior, cognition, and brain health in older adults concluded that sedentary behavior is a lifestyle risk factor independently related to cognitive function and brain health, distinct from physical activity levels and energy expenditure (Gogniat et al., 2025). The two behaviors are not interchangeable. Exercising three times a week does not undo eight to ten hours of daily sitting.
Research into the underlying mechanisms has identified several pathways. A sedentary lifestyle accelerates aging-related decline in motor, metabolic, and cognitive function through chronic subclinical inflammation, mitochondrial dysfunction, and insulin resistance, all of which operate across multiple tissues including the brain and contribute to hippocampal atrophy and cognitive impairment (Ukropcova, 2025).
The practical implication is a shift from thinking about exercise as a weekly box to check to thinking about consistent movement throughout every single day. Breaking up extended periods of sitting with short walks, standing intervals, and regular physical activity is not just good for cardiovascular health. It is one of the most direct, evidence-based strategies available for protecting long-term cognitive performance and reducing dementia risk.
Mistake #3: Ignoring the Gut
This is the mistake that surprises people most, and it is the one that separates the brands, practitioners, and individuals who are genuinely serious about brain health from those who are only addressing the surface of the problem.
The gut-brain axis, the bidirectional communication highway between the gut microbiome and the brain via the vagus nerve, is one of the most significant and fastest-moving areas of neuroscience research right now. And the findings are reshaping what it means to support cognitive health at a foundational level.
A landmark study published in Nature in March 2026, led by researchers at Stanford Medicine and the Arc Institute and funded by the NIH, found that age-related changes in the gut microbiome directly disrupt signaling from the gut to the brain via the vagus nerve, reducing activity in the hippocampus, the brain region responsible for short-term memory, and contributing to measurable cognitive decline. When researchers stimulated the vagus nerve in older mice, memory improved significantly. "What we learned is that the timeline of memory decline is not hardwired; it is actively modulated in the body, and the gastrointestinal tract is a critical regulator of this process," said Dr. Christoph Thaiss, PhD, assistant professor of pathology at Stanford (Thaiss et al., 2026).
A comprehensive systematic review published in Nutrients in January 2026 synthesizing the most recent human research found that current evidence indicates the gut microbiota is linked to cognitive function in both healthy and diseased states, with numerous studies suggesting a potential causal relationship between the two. Alterations in gut microbiota composition among older adults, even in the absence of a diagnosis for cognitive impairment, may act as preliminary biological indicators for Alzheimer's disease or other forms of dementia prior to the onset of mild cognitive impairment (Bagheri et al., 2026).
A 2025 review published in Frontiers in Immunology confirmed that gut bacteria produce metabolites including short-chain fatty acids that affect immune responses and directly influence cognitive functions, with the gut-brain axis now identified as a key pathway in the pathogenesis of neurodegenerative disorders (Zhang et al., 2025).
Roughly 90 percent of the body's serotonin is produced in the gut, not the brain. When the gut microbiome is imbalanced or the gut lining is compromised, inflammatory signals travel via the vagus nerve to the brain, driving brain fog, cognitive fatigue, and mood dysregulation from the inside out. Most brain health conversations, and most brain health supplements, ignore this entirely. They address the brain without addressing the gut that feeds it.
Where Thumos Comes In: A First Step Toward Optimization
Correcting these three mistakes creates the conditions your brain needs to perform and protect itself long term. Sleep and movement are the behavioral foundation. Gut health is the biological one. And supporting all three with targeted, clinical-dose nutritional input is where Thumos Daily Brain + Gut Support enters as a meaningful first step in your cognitive optimization protocol.
Thumos was built by veterans who understood that real performance demands real ingredients at real doses. Every one of the eight ingredients in the formula is grounded in peer-reviewed research, and every dosage is clinical, not cosmetic.
L-Glutamine at 1,000mg fuels the intestinal cell lining that protects gut barrier integrity, directly supporting the gut-brain axis that the latest Stanford research identifies as a primary regulator of cognitive aging. Inulin from Agave at 1,000mg feeds the beneficial bacteria responsible for producing serotonin, GABA, and the short-chain fatty acids that regulate both mood and cognitive function. Together, these two ingredients address the gut-brain foundation that 90 percent of brain supplements never touch.
Cognizin Citicoline at 200mg, one of the most clinically researched nootropics available, supports neuronal membrane integrity and brain energy metabolism, the cellular infrastructure that determines how well the brain sustains cognitive performance under daily demands. L-Tyrosine at 500mg fuels the production of dopamine and norepinephrine for sustained focus and mental drive. L-Theanine at 200mg promotes the calm, alert alpha brainwave state associated with peak cognitive performance. Coenzyme Q10, nano-emulsified at 100mg, powers the mitochondria inside every brain cell. Taurine at 500mg provides neuroprotection at the cellular level. And Natural Caffeine from Green Tea at 50mg delivers clean, sustained mental energy without the cortisol spike that undermines long-term cognitive health.
The three mistakes outlined above each accelerate the neurological decline that robs people of their sharpest years. Thumos is designed to give the brain the biological support it needs to fight back against that process, starting on day one.
Your brain is the most important asset you will ever own. Start protecting it at livethumos.com.
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Works Cited
Alzheimer's Association. 2026 Alzheimer's Disease Facts and Figures: Brain Health in America. Alzheimer's Association, 2026. www.alz.org/news/2026/facts-figures-report-brain-health.
AARP. "Is Age-Related Cognitive Decline Inevitable?" AARP Health, 2025. www.aarp.org/health/conditions-treatments/cognitive-decline-aging.
Bagheri, Soghra, et al. "Gut Microbiota Impact on Cognitive Function in Humans." Nutrients, vol. 18, no. 3, 23 Jan. 2026, p. 369. doi:10.3390/nu18030369.
Biswas, Debadrit, et al. "Sleep Deprivation as a Risk Factor for Cognitive Decline Among Middle-Aged Adults." Bioinformation, vol. 21, no. 10, 31 Oct. 2025, pp. 3484-3487. doi:10.6026/973206300213484.
Gogniat, Marissa A., et al. "Sedentary Behavior, Cognition, and Brain Health in Older Adults: A Systematic Review." Frontiers in Aging Neuroscience, vol. 17, 8 July 2025. doi:10.3389/fnagi.2025.1622049.
National Institutes of Health. "Weakened Gut-Brain Connection May Contribute to Memory Loss." NIH Research Matters, 12 May 2026. www.nih.gov/news-events/nih-research-matters/weakened-gut-brain-connection-may-contribute-memory-loss.
Sun, Zhiwei, et al. "The Effects of Sleep Deprivation on Cognitive Flexibility: A Scoping Review of Outcomes and Biological Mechanisms." Frontiers in Neuroscience, vol. 19, 22 July 2025. doi:10.3389/fnins.2025.1626309.
Thaiss, Christoph A., et al. "Intestinal Interoceptive Dysfunction Drives Age-Associated Cognitive Decline." Nature, 11 Mar. 2026. doi:10.1038/s41586-026-10191-6.
Ukropcova, Barbara. "Ameliorating Aging-Associated Cognitive Decline by Physical Exercise: Multi-Organ Integrative Approach." Alzheimer's and Dementia, 23 Dec. 2025. doi:10.1002/alz70860_102754.
University of Pittsburgh. "Study Reveals Sedentary Behavior Is a Risk Factor for Alzheimer's." UPMC News, 13 May 2025. www.upmc.com/media/news/051325-sedentary-risk.
Younas, Aimen, et al. "The Impact of Sleep Deprivation on Brain Fog, Cognitive Decline, and Cardiovascular Risk in Young Adults." Cureus, vol. 17, no. 5, 8 May 2025. doi:10.7759/cureus.83757.
Zhang, Rui, et al. "The Gut Microbiome, Immune Modulation, and Cognitive Decline: Insights on the Gut-Brain Axis." Frontiers in Immunology, vol. 16, 22 Jan. 2025. doi:10.3389/fimmu.2025.1529958.