7 Needs context
Athletes following a ketogenic diet did not experience deterioration in physical performance compared to those on a high-carbohydrate diet.
"What we found is that when athletes were either on a ketogenic diet or on a high carb diet, the ketogenic diet did not produce any deterioration in physical performance." (said at 0:00:00)
The claim that a ketogenic diet causes no deterioration in athletic performance compared to a high-carbohydrate diet requires important qualification. Systematic reviews and position stands show that the impact of a ketogenic diet is highly dependent on exercise intensity, duration, and adaptation time. For maximal strength, resistance training, and moderate-intensity endurance (such as VO2 max and time to exhaustion), evidence indicates performance is generally preserved compared to high-carbohydrate diets. However, for high-intensity endurance, exercise economy, and elite-level competition, ketogenic diets frequently result in performance decrements or reduced efficiency compared to carbohydrate-rich diets.
- partial: International society of sports nutrition position stand: ketogenic diets. (Journal of the International Society of Sports Nutrition 2024) · cited 18x in the literature
"A ketogenic diet has largely neutral or detrimental effects on athletic performance compared to a diet higher in carbohydrates and lower in fat, despite achieving significantly elevated levels of fat oxidation during exercise (~1.5 g/min)... All studies involving elite athletes showed a performance decrement from a ketogenic diet, all lasting six weeks or less." (abstract, conclusions, passage verified)
pubmedfull study (doi) - supports: Effects of ketogenic diet on muscle mass, strength, aerobic metabolic capacity, and endura… (Journal of health, population, and nutrition 2025) · cited 3x in the literature
"A total of 33 studies were analyzed, revealing no significant differences between the KD and other diets in muscle mass... muscle power... and strength... The VO 2max and VO 2max relative to body weight, treadmill time to exhaustion, and rating of perceived exertion were not significantly affected by KD." (abstract, results)
pubmedfull study (doi) - partial: Effects of Low-Carbohydrate and Ketogenic Diets on Aerobic Performance in Trained Athletes… (Nutrients 2026) · cited 1x in the literature
"Maximal aerobic capacity (VO 2 max) was preserved in 50.0% of studies, with 11.1% documenting improvements. Submaximal exercise economy showed the greatest sensitivity, with 50.0% documenting impaired efficiency. Time to exhaustion demonstrated context-dependent effects, with 69.2% maintaining performance." (abstract, results, passage verified)
pubmedfull study (doi)
Administration of exogenous ketones without dietary changes improves cognitive retention during acute hypoxic exposure at altitudes between 15,000 and 20,000 feet.
"we've studied just the mere application of ketones independent of diet change and see profound effects in various conditions, including in extreme environments like high altitude hypoxic exposure for special operations command grant looking at the ability to improve resilience against hypoxia exposure. Anywhere between 15 to 20,000 foot altitude immediate exposure and it increased the ability to have retained cognition in these extreme environments." (said at 0:25:30)
Exogenous ketone supplementation (such as ketone monoesters) taken acutely without dietary changes has been shown in controlled laboratory studies to partially attenuate declines in specific cognitive and psychomotor functions—such as reaction time on vigilance tests and code substitution performance—during severe acute hypoxic exposure simulating altitudes of 15,000 to 20,000 feet (4,500 to 6,100 m). However, the evidence is domain-specific and mixed: several randomized trials have found that while exogenous ketones improve blood oxygen saturation or neural signaling under hypoxia, they do not consistently improve broader cognitive test batteries, complex task performance, or real-world field performance during high-altitude operations.
- supports: A Metabolic Intervention for Improving Human Cognitive Performance During Hypoxia. (Aerospace medicine and human performance 2021) · cited 20x in the literature
"Significant hypoxia effects were likewise observed for a code substitution task (Ph2 0.487), indicating that performance on the task was significantly disrupted by the hypoxia stressor. KE consumption had a significant effect on blink duration (Ph2 0.270) and the code substitution task (Ph2 0.309). DISCUSSION: These finding suggest that some effects of acute hypoxia can be mitigated by nutritional ketosis." (abstract, results, passage verified)
pubmedfull study (doi) - partial: Ketone monoester attenuates oxygen desaturation during weighted ruck exercise under acute … (Experimental physiology 2024) · cited 10x in the literature
"The decline in oxygen saturation during hypoxic exposure was attenuated in KME conditions by 2.4%-4.2% (P < 0.05) compared with placebo. Outcomes of cognitive performance tasks, in the form of the Defense Automated Neurobehavioral Assessment (DANA) code substitution task, the Stroop color and word task, and a shooting simulation, did not differ between trials before and during hypoxic exposure." (abstract, results, passage verified)
pubmedfull study (doi) - supports: Effect of Acute Ingestion of a Ketone Monoester on Psychomotor Vigilance During Acute Seve… (Military medicine 2026)
"The hypoxia-induced decline in mean reaction time was attenuated (P = .002) with KME, which resulted in a faster mean reaction time [25.5 (10.7, 40.3) milliseconds] in hypoxia compared to PLA. No significant differences between KME and PLA were observed for the deleterious effect of hypoxia on other outcome measures from the psychomotor vigilance test. Acute ingestion of the R-BD R-βHB KME partially attenuated the decline in sustained attention and vigilance that occurred during acute exposure to severe hypoxia, and may support cognitive resilience under environmental stress." (abstract, results, passage verified)
pubmedfull study (doi)
Beta-hydroxybutyrate alters epigenetic gene expression through beta-hydroxybutyrylation and activates FOXO antioxidant genes.
"There's actually something called beta-hydroxybutyrylation, which is an epigenetic change... And one of those genes is is a FOXO gene, which specifically is an antioxidant-producing gene, which so as a way of actually causing anti or scavenging oxidative stress molecules." (said at 0:40:35)
Beta-hydroxybutyrate (βOHB) acts as an epigenetic regulator via both histone deacetylase (HDAC) inhibition and lysine beta-hydroxybutyrylation. In cellular and rodent models, βOHB increases histone acetylation at the Foxo3a promoter (via class I HDAC inhibition), upregulating FOXO3A transcription and conferring protection against oxidative stress. FOXO3A is a transcription factor that upregulates antioxidant enzymes (such as superoxide dismutase and catalase) rather than directly producing antioxidant molecules. While the speaker conflates beta-hydroxybutyrylation with the HDAC-inhibition-driven histone acetylation mechanism originally demonstrated for FOXO activation, βOHB is an established epigenetic regulator that enhances FOXO-mediated antioxidant pathways in preclinical models.
- supports: Suppression of oxidative stress by β-hydroxybutyrate, an endogenous histone deacetylase in… (Science (New York, N.Y.) 2013) · cited 1758x in the literature
"Inhibition of HDAC by βOHB was correlated with global changes in transcription, including that of the genes encoding oxidative stress resistance factors FOXO3A and MT2. Treatment of cells with βOHB increased histone acetylation at the Foxo3a and Mt2 promoters, and both genes were activated by selective depletion of HDAC1 and HDAC2. Consistent with increased FOXO3A and MT2 activity, treatment of mice with βOHB conferred substantial protection against oxidative stress." (abstract, results, passage verified)
pubmedfull study (doi) - context: β-hydroxybutyrate as an Anti-Aging Metabolite. (Nutrients 2021) · cited 139x in the literature
"Besides, it serves as an epigenetic regulator in terms of histone methylation, acetylation, β-hydroxybutyrylation to delay various age-related diseases." (abstract, results, passage verified)
pubmedfull study (doi)
In the 1960s, Jonas Bergström developed the percutaneous muscle biopsy technique and showed that glucose is stored in muscle as glycogen.
"It wasn't until the 1960s where a physician named Jonas Bergström discovered the ability to actually stick a syringe into the muscle and do something called a muscle biopsy, so, they called the Bergström muscle biopsy, where they actually suctioned out a piece of muscle. And what they were finding is, oh wow, lo and behold, when we pull out muscle and analyze that muscle tissue, glucose was being stored as something called glycogen." (said at 0:54:05)
The speaker accurately describes Jonas Bergström's introduction of the percutaneous needle muscle biopsy technique in the 1960s, which used a specialized needle and suction to obtain skeletal muscle samples in humans, revolutionizing the study of human exercise physiology and glycogen dynamics in vivo. However, the claim that this led to the initial discovery that glucose is stored in muscle as glycogen is historically inaccurate; glycogen and its role as a stored carbohydrate in liver and muscle had been established more than a century earlier (initially isolated by Claude Bernard in the 1850s and extensively characterized in muscle throughout the early 20th century). Bergström and colleagues used the biopsy technique to demonstrate how human muscle glycogen content fluctuates, depleting during exercise and supercompensating with dietary carbohydrate.
- supports: Human Skeletal Muscle Biopsy Procedures Using the Modified Bergström Technique (Journal of Visualized Experiments 2014) · cited 119x in the literature
"This video describes the percutaneous biopsy technique using a modified Bergström needle to obtain skeletal muscle tissue samples from the vastus lateralis of human subjects. The Bergström needle consists of an outer cannula with a small opening ('window') at the side of the tip and an inner trocar with a cutting blade at the distal end... Next, suction is applied to the inner trocar, the outer trocar is pulled back, skeletal muscle tissue is drawn into the window of the outer cannula by the suction, and the inner trocar is rapidly closed, thus cutting or clipping the skeletal muscle tissue sample." (abstract, results, passage verified)
openalexfull study (doi) - context: Postexercise muscle glycogen resynthesis in humans (Journal of Applied Physiology 2016) · cited 232x in the literature
"Since the pioneering studies conducted in the 1960s in which glycogen status was investigated using the muscle biopsy technique, sports scientists have developed a sophisticated appreciation of the role of glycogen in cellular adaptation and exercise performance, as well as sites of storage of this important metabolic fuel." (abstract, results, passage verified)
openalexfull study (doi) - context: A century of exercise physiology: key concepts in regulation of glycogen metabolism in ske… (European Journal of Applied Physiology 2022) · cited 40x in the literature
"Glycogen is a branched, glucose polymer and the storage form of glucose in cells. Glycogen has traditionally been viewed as a key substrate for muscle ATP production during conditions of high energy demand and considered to be limiting for work capacity and force generation under defined conditions... Thus, despite the extensive amount of knowledge accrued during the past 100 years, several critical questions remain regarding the regulation of glycogen metabolism and its role in living muscle." (abstract, results, passage verified)
openalexfull study (doi)
In the medical literature, 70 mg/dL (3.9 mmol/L) is typically defined as the threshold for hypoglycemia because the majority of individuals experience symptoms at or below that level.
"in the medical literature 70 mg/dL or 3.9 mmol is usually the threshold for hypoglycemia. Why is it used as a threshold for hypoglycemia? Because the vast majority of people will experience symptoms at or below that level." (said at 1:03:34)
While 70 mg/dL (3.9 mmol/L) is widely established in clinical practice guidelines and consensus statements as the alert threshold for hypoglycemia, the physiological rationale given is inaccurate. Experimental clamp studies establishing the hierarchy of glycemic thresholds show that autonomic counterregulatory hormones (epinephrine, glucagon) begin to release at approximately 65–68 mg/dL, whereas autonomic symptoms (such as sweating, tremor, and palpitations) do not typically occur until glucose drops to approximately 55–58 mg/dL (and neuroglycopenic symptoms below ~50 mg/dL). The 70 mg/dL cutoff is selected as a safety threshold because it approximates the upper limit of physiological counterregulation, providing an early margin of safety to prevent symptomatic or neuroglycopenic hypoglycemia, rather than because symptoms occur at 70 mg/dL.
- context: Hierarchy of glycemic thresholds for counterregulatory hormone secretion, symptoms, and ce… (The American journal of physiology 1991) · cited 567x in the literature
"Activation of glucagon, epinephrine, norepinephrine, and growth hormone secretion began at arterialized venous plasma glucose concentrations of 68 +/- 1, 68 +/- 1, 65 +/- 1, and 67 +/- 2 (SE) mg/dl, respectively. Autonomic symptoms (anxiety, palpitations, sweating, irritability, and tremor) began at 58 +/- 2 mg/dl, which was significantly (P = 0.0001) lower. Neuroglycopenic symptoms (hunger, dizziness, tingling, blurred vision, difficulty thinking, and faintness) and deterioration in cognitive function tests began at 51 +/- 3 and 49 +/- 2 mg/dl, respectively" (abstract, results, passage verified)
pubmedfull study (doi)
An analysis of Framingham Heart Study data published in the Journal of Prevention of Alzheimer's Disease found that consuming an average of one serving per day of ultra-processed foods was associated with a 13% increased risk of developing Alzheimer's over a 6-year period.
"A study came out evaluation of Framingham Heart Study uh data in the Journal of Prevention of Alzheimer's—what a journal. Can you imagine? Prevention of Alzheimer's. Indicating that over the 6-year period, averaging one serving a day, just one serving a day of ultra-processed foods, based upon what you and I've been talking about, was associated with a 13% increased risk of developing Alzheimer's during that 6-year period" (said at 1:21:12)
A prospective cohort study of 1,375 Framingham Heart Study Offspring participants published in The Journal of Prevention of Alzheimer's Disease found that each additional serving per day of ultra-processed food was associated with a 13% increased risk of Alzheimer's disease (HR = 1.13, 95% CI: 1.03–1.25) after adjusting for diet quality and metabolic risk factors. However, this association was observed specifically among participants who were under 68 years of age at baseline over a mean follow-up of 12.7 ± 6.0 years (dietary data were collected across examination cycles 5 and 7, approximately 6 years apart), and no significant association was found in older participants. Additionally, the 13% figure reflects an incremental risk per serving per day, not the absolute effect of consuming only a single serving.
- context: Ultra-processed food consumption and risk of dementia and Alzheimer's disease: The Framing… (The journal of prevention of Alzheimer's disease 2025) · cited 22x in the literature
"Among participants who were <68 years of age at baseline, each serving per day of ultra-processed food was associated with 13 % increased risk for Alzheimer's disease (HR = 1.13, 95 % CI:1.03-1.25), and consumption of ≥10 servings/day vs. <10 servings/day of ultra-processed food was associated with a 2.7-fold increase in Alzheimer's disease risk (HR = 2.71, 95 % CI:1.18-6.24), after adjustment for age, sex, education, total energy, metabolic factors and diet quality." (abstract, results, passage verified)
pubmedfull study (doi)
An analysis of Framingham Heart Study data found that consuming 10 or more servings of ultra-processed foods per day was associated with a 2.7-fold increased risk of developing Alzheimer's disease.
"Having 10 or more servings of ultra-processed foods a day, it seems like a lot. You know as well as I do, that's not uncommon when you add in the soft drinks, the flavored yogurts, you name it, was associated with a 2.7-fold increased risk of developing Alzheimer's." (said at 1:21:41)
A prospective analysis of the Framingham Heart Study (PMID: 39863327) did report that consuming 10 or more servings per day of ultra-processed food was associated with a 2.7-fold increased risk of developing Alzheimer's disease (hazard ratio 2.71, 95% CI: 1.18–6.24). However, this specific finding was restricted to participants who were younger than 68 years of age at baseline; no statistically significant association was observed among participants aged 68 years or older, and the findings are observational.
- context: Ultra-processed food consumption and risk of dementia and Alzheimer's disease: The Framing… (The journal of prevention of Alzheimer's disease 2025) · cited 22x in the literature
"Among participants who were <68 years of age at baseline, each serving per day of ultra-processed food was associated with 13 % increased risk for Alzheimer's disease (HR = 1.13, 95 % CI:1.03-1.25), and consumption of ≥10 servings/day vs. <10 servings/day of ultra-processed food was associated with a 2.7-fold increase in Alzheimer's disease risk (HR = 2.71, 95 % CI:1.18-6.24), after adjustment for age, sex, education, total energy, metabolic factors and diet quality." (abstract, results, passage verified)
pubmedfull study (doi)
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.