FoundMyFitness · 2018-10-01 · Rhonda Patrick (host), Dale Bredesen
Dr. Dale Bredesen on Preventing and Reversing Alzheimer's Disease
47 claims checked against research: 1 contradicted 5 overstated 1 needing context 35 supported 5 unverified
5 Overstated
Elevated homocysteine levels correlate with more rapid cerebral gray matter and hippocampal volume loss, and normalizing homocysteine halts this volume decline.
"And of course, it's been published that you have a more rapid decline in your cerebral gray matter volume and hippocampal volume if you have a high homocysteine... but then if you improved the homocysteine and brought it back to normal... people actually stopped their decline and leveled off." (said at 0:20:50)
In older adults with mild cognitive impairment and elevated baseline homocysteine, randomized trial data (such as the VITACOG trial) show that high homocysteine is associated with faster whole-brain and gray matter atrophy (including within the medial temporal lobe), and that homocysteine-lowering therapy with B vitamins (folate, B6, and B12) significantly slows the rate of accelerated volume loss (by up to 53% for whole-brain atrophy in those with high baseline homocysteine). However, the claim overstates the effect by asserting that brain volume loss completely stopped or leveled off; the treatment slowed accelerated atrophy toward typical aging rates rather than halting volume decline entirely.
- partial: Homocysteine-lowering by B vitamins slows the rate of accelerated brain atrophy in mild co… (PloS one 2010) · cited 814x in the literature
"The mean rate of brain atrophy per year was 0.76% [95% CI, 0.63-0.90] in the active treatment group and 1.08% [0.94-1.22] in the placebo group (P = 0.001). The treatment response was related to baseline homocysteine levels: the rate of atrophy in participants with homocysteine >13 µmol/L was 53% lower in the active treatment group (P = 0.001)." (abstract, results, passage verified)
pubmedfull study (doi) - partial: Preventing Alzheimer's disease-related gray matter atrophy by B-vitamin treatment. (Proceedings of the National Academy of Sciences of the United States of America 2013) · cited 526x in the literature
"In the placebo group, higher homocysteine levels at baseline are associated with faster GM atrophy, but this deleterious effect is largely prevented by B-vitamin treatment. We additionally show that the beneficial effect of B vitamins is confined to participants with high homocysteine (above the median, 11 µmol/L) and that, in these participants, a causal Bayesian network analysis indicates the following chain of events: B vitamins lower homocysteine, which directly leads to a decrease in GM atrophy, thereby slowing cognitive decline." (abstract, results, passage verified)
pubmedfull study (doi)
Patients categorized with type 3 (toxic or cortical) Alzheimer's disease characteristically present with low serum zinc, elevated copper-to-zinc ratios, and low serum triglycerides.
"many of the people with the type 3, the toxic subtype, have low serum zinc, high copper-to-zinc ratios, and low triglycerides." (said at 0:09:48)
In a 2015 paper introducing a proposed metabolic subtyping system for Alzheimer's disease, Dr. Dale Bredesen described 'type 3' (a cortical/toxic subtype) as being associated with 'striking zinc deficiency' (PMID: 26343025). However, this classification framework and its associated biomarker claims—including low serum zinc, elevated copper-to-zinc ratios, and low triglycerides—are derived from small case reports and observational hypothesis-generating work rather than validated clinical trials or established diagnostic guidelines.
- partial: Metabolic profiling distinguishes three subtypes of Alzheimer's disease. (Aging 2015) · cited 81x in the literature
"The third type is a very distinctive clinical entity that affects relatively young individuals, extends beyond the typical Alzheimer's disease initial distribution to affect the cortex widely, is characterized by early non-amnestic features such as dyscalculia and aphasia, is often misdiagnosed or labeled atypical Alzheimer's disease, typically affects ApoE4-negative individuals, and is associated with striking zinc deficiency." (abstract, results, passage verified)
pubmedfull study (doi)
Individuals who are APOE4-positive absorb dietary fat better than those who are APOE4-negative.
"If you are APOE4-positive, you're actually a better fat absorber, as you know, so you want to want to make that 14 to 16 hours." (said at 0:31:00)
The claim that APOE4 carriers absorb dietary fat or cholesterol more efficiently is based primarily on indirect surrogate markers (such as serum plant sterols/phytosterols), where APOE4 carriers often show elevated ratios. However, direct mass-balance and tracer studies measuring intestinal absorption efficiency have demonstrated no significant differences across APOE phenotypes. Elevated postprandial triglyceride-rich lipoproteins (chylomicron remnants) observed in APOE4 carriers are primarily driven by delayed clearance and hepatic processing rather than superior intestinal absorption of dietary fat.
- supports: Apolipoprotein E phenotype regulates cholesterol absorption in healthy 13-month-old childr… (Pediatric research 2001) · cited 45x in the literature
"The 16 apoE4 children had 30% to 50% higher cholesterol-adjusted campesterol and sitosterol concentrations in serum than the 20 apoE 3/3 children (p = 0.002 and p = 0.02, respectively)." (abstract, results, passage verified)
pubmedfull study (doi) - contradicts: Efficiency of intestinal cholesterol absorption in humans is not related to apoE phenotype… (Journal of lipid research 2003) · cited 37x in the literature
"Cholesterol absorption did not differ between the three groups of subjects and averaged 38 +/- 2% (mean +/- SEM) in normolipemic E2/2, 37 +/- 4% in type III hyperlipemic E2/2, and 41 +/- 3% in E4/4 subjects, respectively. Dietary intake of fat and cholesterol had no influence on cholesterol absorption efficiency." (abstract, results, passage verified)
pubmedfull study (doi) - context: Prolonged postprandial responses of lipids and apolipoproteins in triglyceride-rich lipopr… (The Journal of clinical investigation 1996) · cited 98x in the literature
"In both groups, TRL apo B48 increased at 3 h but returned to postabsorptive values at 6 h only in the apo E3/3 group; in the apo E4/3 group the concentration of apo B48 at 6 h was 80% higher than postabsorptive values... These observations suggest that clearance of intestinal and hepatogenous TRL remnants is impaired in young men with an apo E4/3 phenotype." (abstract, results, passage verified)
pubmedfull study (doi)
Alzheimer's and cognitive decline patients maintain better outcomes when blood beta-hydroxybutyrate levels are between 1.5 mM and 4.0 mM.
"We're finding that people who have higher ketone levels, 1.5 millimolar to 4 millimolar beta-hydroxybutyrate, tend to do better than those who are down lower, APOE4-positive and APOE4-positive or negative." (said at 0:33:34)
While systematic review and meta-analytic evidence indicates that inducing ketosis or supplementing with exogenous ketones can yield modest overall cognitive improvements (standardized mean difference of 0.29), there is no controlled clinical evidence establishing that a specific blood beta-hydroxybutyrate window of 1.5 mM to 4.0 mM produces superior clinical outcomes compared to lower levels in patients with cognitive decline or Alzheimer's disease regardless of APOE4 status. Targeted ketone levels within multimodal programs (such as the ReCODE / KetoFLEX 12/3 protocol) are based on preliminary observational series and uncontrolled pilot studies rather than isolated, dose-comparison trials.
- context: The effect of exogenous ketone bodies on cognition across health and disease: a systematic… (Frontiers in nutrition 2026) · cited 2x in the literature
"EK supplementation was associated with a statistically significant improvement in cognitive performance compared with placebo (SMD = 0.29, 95% CI 0.16-0.41; p < 0.001). Sub-group analyses did not show statistically significant differences between the type of supplementation ( p = 0.083), study duration (acute vs. intermediate; p = 0.11), population type (healthy vs. Alzheimer's disease; p = 0.077), or the presence of acute cognitive stressors ( p = 0.89)." (abstract, results, passage verified)
pubmedfull study (doi) - context: KetoFLEX 12/3 Diet and Cognitive Health: A Precision-Nutrition Perspective on Mechanisms, … (Nutrients 2026)
"Although much of the current evidence remains mechanistic, observational, or derived from multimodal intervention studies, the framework offers a biologically plausible precision-nutrition model that may inform future research and clinical investigation in cognitive decline." (abstract, conclusions, passage verified)
pubmedfull study (doi)
Research by Stephen Genuis showed that cadmium concentration in human sweat can be over 1,000 times higher than in blood.
"you know, some nice work by Dr. Stephen Genuis from Canada, who showed that if you look at composition of sweat compared to the blood, there are certain toxins that are very high, cadmium being the big one, you know, over a thousand times increase in sweat." (said at 0:53:00)
Research by Dr. Stephen Genuis and colleagues (including the Blood, Urine, and Sweat study and a 2012 systematic review) found that heavy metals like cadmium are excreted through perspiration and can be more concentrated in sweat than in blood plasma or serum. In some participants, toxic elements were measurable in sweat even when non-detectable in serum. However, the claim that cadmium concentration in sweat is 'over 1,000 times' higher than in blood exaggerates the findings published in these studies. Furthermore, the body of evidence relies on small observational samples and descriptive reviews, providing low certainty overall.
- partial: Blood, urine, and sweat (BUS) study: monitoring and elimination of bioaccumulated toxic el… (Archives of environmental contamination and toxicology 2011) · cited 131x in the literature
"Presumably stored in tissues, some toxic elements readily identified in the perspiration of some participants were not found in their serum." (abstract, results, passage verified)
pubmedfull study (doi) - partial: Arsenic, cadmium, lead, and mercury in sweat: a systematic review. (Journal of environmental and public health 2012) · cited 108x in the literature
"Cadmium was more concentrated in sweat than in blood plasma." (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.