DavidPerlmutterMD · 2019-03-02 · David Perlmutter (host), Sara Gottfried

Weight Loss and the Brain - with Dr. Sara Gottfried | The Empowering Neurologist EP. 82

37 research-tied claims examined: 2 contradicted 4 overstated 7 context 19 supported 1 corroborated online 4 unverified

Contradicted by research

Women tend to have a larger hippocampus up until a certain age, while men tend to have a larger cerebellum.

"in general, we know that women tend to have a bigger hippocampus, at least up until a certain age, and men tend to have a larger cerebellum, which is responsible for movement and coordination and other things." (said at 0:09:20)

The claim that women tend to have a larger hippocampus (up to a certain age) is contradicted by meta-analytic MRI evidence. Meta-analyses of structural brain imaging show that uncorrected absolute hippocampal volume is larger in men across all age groups, primarily reflecting larger overall brain size in males. When adjusted for total brain volume or intracranial volume, there is no statistically significant sex difference in hippocampal volume.

contradicts: The human hippocampus is not sexually-dimorphic: Meta-analysis of structural MRI volumes. (NeuroImage 2016) · cited 196x in the literature
"We found that uncorrected HCV was reliably larger in males, with Hedges' g values of 0.545 for left hippocampus, 0.526 for right hippocampus, and 0.557 for bilateral hippocampus. Meta-regression revealed no effect of age on the sex difference in left, right, or bilateral HCV... studies reporting HCVs corrected for individual differences in TBV or ICV revealed no significant sex differences in left and right HCVs... The frequent claim that women have a disproportionately larger hippocampus than men was not supported." (abstract, results and conclusions, passage verified)
pubmed full study (doi)
contradicts: Dump the "dimorphism": Comprehensive synthesis of human brain studies reveals few male-fem… (Neuroscience and biobehavioral reviews 2021) · cited 371x in the literature
"Males' brains are larger than females' from birth, stabilizing around 11 % in adults. This size difference accounts for other reproducible findings: higher white/gray matter ratio, intra- versus interhemispheric connectivity, and regional cortical and subcortical volumes in males." (abstract, results, passage verified)
pubmed full study (doi)

0:47:40 Sara Gottfriedcontradictedhigh

Only about 10% to 15% of the risk for chronic disease is genetic, while 85% to 90% is determined by environmental and lifestyle factors.

"And when it comes to something like Alzheimer's disease, or if you look at chronic disease in general, only about 10 to 15% of your risk of chronic disease is related to your genes. The rest, which is what we have a fair amount of control over, the 85 to 90%, is your environment, much of which is determined by your lifestyle choices, how you architect your day." (said at 0:47:40)

The claim that genetic factors account for only 10% to 15% of the risk of chronic diseases such as Alzheimer's disease is contradicted by genetic epidemiological evidence. In the largest population-based twin studies, the heritability of late-onset Alzheimer's disease is estimated to be between 58% and 79%, with non-shared environmental factors explaining the remainder. While environmental and lifestyle factors play important, modifiable roles in chronic disease progression and risk reduction, genetic liability accounts for a substantially larger proportion of disease risk than 10% to 15% across many major chronic conditions, particularly Alzheimer's disease.

contradicts: Role of genes and environments for explaining Alzheimer disease. (Archives of general psychiatry 2006) · cited 1876x in the literature
"Heritability for AD was estimated to be 58% in the full model and 79% in the best-fitting model, with the balance of variation explained by nonshared environmental influences." (abstract, results, passage verified)
pubmed full study (doi)
contradicts: Alzheimer disease is (sometimes) highly heritable: Drivers of variation in heritability es… (PLoS genetics 2025) · cited 6x in the literature
"While numerous studies have established substantial genetic contribution for LOAD, the interpretation of heritability estimates remains challenging." (abstract, background, passage verified)
pubmed full 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.