HoldsUp

Mark Mattson

Johns Hopkins University School of Medicine

Mark Mattson is a neuroscientist, an adjunct professor of neuroscience at the Johns Hopkins University School of Medicine, and the former chief of the Neuroscience Research Laboratory at the National Institute on Aging. His research focuses on the cellular and molecular effects of dietary restriction, intermittent fasting, and metabolic switching on aging, longevity, and metabolic traits. He also studies mechanisms of neuroprotection, synaptic plasticity, neurogenesis, and the principle of hormesis in brain health.

82 claims checked on air: 4 context 2 contradicted 68 supported 8 unverified

What they said on air - unverified

7 citing their own research

0:32:40unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

At least 90% of neurons in the human brain use glutamate as their neurotransmitter and are distributed throughout the cortex, hippocampus, brainstem, and basal ganglia.

"it turns out that at least 90% of the nerve cells in your brain deploy glutamate as a neurotransmitter, and those neurons are distributed in every brain region throughout the cerebral cortex, other brain regions—hippocampus, brainstem, basal ganglia" (said at 0:32:40)

No published record matching the claim that at least 90% of neurons in the human brain deploy glutamate as their neurotransmitter across the cortex, hippocampus, brainstem, and basal ganglia was located; this does not prove the claim false.

1:02:37unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

The human liver produces cytochrome P450 enzymes that rapidly remove potentially toxic ingested plant chemicals.

"The third way, which is interesting from human environmental health standpoint, is we have evolved enzymes in our liver that rapidly remove these potentially toxic chemicals when we eat them; they're called cytochrome P450s." (said at 1:02:37)

No published record matching the claim that the human liver produces cytochrome P450 enzymes that rapidly remove potentially toxic ingested plant chemicals was located; this does not prove the claim false.

1:37:24unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

Male rats subjected to 40% daily calorie restriction maintain their sperm count and lose less body weight than females over several months.

"Oh, then, interestingly, the males, even on the 40% daily calorie restriction, so the males, their sperm count didn't change and they didn't lose as much body weight as the females during over these months." (said at 1:37:24)

No published record matching the claim that male rats subjected to 40% daily calorie restriction maintain their sperm count and lose less body weight than females over several months was located; this does not prove the claim false.

1:42:00unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

Intermittent fasting causes a decrease in glucocorticoid receptor (GR) levels and sustains mineralocorticoid receptor (MR) levels in the mouse hippocampus.

"So we did a study where we measured levels of GR and MR, the two different receptors for cortisol, in the hippocampus of mice that had been on every-other-day fasting or ad libitum control feeding. And what we found is that in contrast to chronic uncontrollable stress, the intermittent fasting caused a decrease in levels of GR and a sustained level of MR." (said at 1:42:00)

No published record matching the claim that every-other-day fasting causes a decrease in glucocorticoid receptor (GR) levels while sustaining mineralocorticoid receptor (MR) levels in the mouse hippocampus was located; this does not prove the claim false.

1:50:11unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

Mice will die if deprived of food for more than three days.

"the mice, they die if they don't have food if you go beyond three days or so, they will die, you know." (said at 1:50:11)

No published record matching the claim that mice will die if deprived of food for more than three days was located; this does not prove the claim false.

1:51:12unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

In rodents, ketone levels increase within 1 to 2 hours of fasting, whereas in humans it takes 10 to 12 hours.

"even with ketones, it's true that in the animals the ketones go up within an hour or two of fasting, whereas in humans it's obviously dependent on 10 to 12, right." (said at 1:51:12)

No published record matching the claim that ketone levels increase within 1 to 2 hours of fasting in rodents compared to 10 to 12 hours in humans was located; this does not prove the claim false.

2:11:17unverifiedlowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

Laboratory rodents typically die from cancers and kidney disease rather than cardiovascular disease or diabetes.

"But the animals don't die from cardiovascular disease typically, or diabetes; they die from cancers, um kidney disease are kind of the two main causes of death." (said at 2:11:17)

No published record specifically quantifying the predominant natural causes of death across standard strains of laboratory rodents (comparing cancer and renal disease against cardiovascular disease or diabetes) was located among the retrieved literature; this does not prove the claim false.

2:20:35unverifiedvery lowDr. Mark Mattson on the Benefits of Stress, Metabolic Switch

Ketone ester administration produced rapid, noticeable improvements in Parkinson's disease symptoms in a patient studied by Richard Veech.

"Richard Veech, he interacted with like he had a friend who had Parkinson's disease, and he took the ketone ester and and claimed that had really clear beneficial effects on his Parkinson's symptoms and that are fairly rapid." (said at 2:20:35)

No published record matching an account or case report by Richard Veech regarding rapid Parkinson's disease symptom improvement in a friend or patient following ketone ester administration was located; this does not prove the claim false. While Veech and colleagues published foundational preclinical work demonstrating that beta-hydroxybutyrate protects against neurotoxicity in cell and animal models of Parkinson's disease, no published clinical case report documenting this specific patient interaction exists in the medical literature.

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