HoldsUp

Ben Greenfield

Ben Greenfield is a biohacker and performance coach with a background in bodybuilding and Ironman triathlons. His work focuses on exercise, health, and moving away from extreme physical strain toward balanced workout approaches.

31 claims checked on air: 5 context 4 contradicted 4 overstated 15 supported 3 unverified

What they said on air - context

0:05:57needs contextmoderateWhy I Stopped 'Biohacking' and Started Living | Ben Greenfie

Excessive carbohydrate restriction combined with excessive exercise impairs thyroid function, testosterone production, and joint proteoglycans.

"if you excessively restrict carbs, you just don't have enough for thyroid, for testosterone, for the, you know, proteoglycans and joints. I think you can basically destroy yourself with excessive carb restriction married to excessive exercise." (said at 0:05:57)

The speaker claims that excessive carbohydrate restriction combined with excessive exercise impairs thyroid function, testosterone production, and joint proteoglycans. In sports physiology, the combination of high exercise energy expenditure and low energy/carbohydrate availability (part of the Relative Energy Deficiency in Sport, or RED-S, spectrum) is well-documented to suppress the hypothalamic-pituitary-gonadal and thyroid axes. Research reviews confirm that energy and carbohydrate deficits relative to exercise demand lead to reduced testosterone in males and altered thyroid hormone signaling pathways (including reductions in total or free triiodothyronine [T3]). However, attributing these endocrine impairments specifically and exclusively to carbohydrate restriction rather than total low energy availability (LEA) remains nuanced, and evidence linking carbohydrate restriction directly to joint proteoglycan degradation in exercisers is preliminary/indirect.

0:42:16needs contextvery lowWhy I Stopped 'Biohacking' and Started Living | Ben Greenfie

The HeartMath Institute published research showing that the electromagnetic signals produced by the human heart or brain can affect the energy of people around them.

"You've got the, you know, you look at like the research by the HeartMath Institute on the electromagnetic signal produced by the brain or produced by the heart that can actually affect the energy of those around you." (said at 0:42:16)

The HeartMath Institute and its researchers (e.g., Rollin McCraty) have published several papers and narrative reviews proposing hypotheses and preliminary observational studies regarding heart-generated electromagnetic fields and physiological synchronization (such as heart rate variability synchronization) between individuals. For example, a publication in *Frontiers in Public Health* discusses the hypothesis that biomagnetic fields produced by the human heart may mediate heart rate variability (HRV) synchronization between people. However, these reports represent early-stage theoretical frameworks, exploratory correlations, or uncontrolled observational findings rather than established physiological proof that heart or brain electromagnetic fields directly transmit energy to alter the energy of surrounding people. High-quality controlled experimental evidence confirming such energetic field-mediated interactions is lacking.

0:42:51needs contextlowWhy I Stopped 'Biohacking' and Started Living | Ben Greenfie

Dunbar's number is 150, representing the approximate limit of people with whom a human can maintain stable social relationships.

"beyond just, you know, Dunbar's number is 150, right? The the the approximate network of people that we're able to to interact with and stay in touch with." (said at 0:42:51)

The speaker accurately defines the theoretical concept of 'Dunbar's number' as approximately 150 individuals, which evolutionary anthropologist Robin Dunbar proposed as the cognitive limit for stable human social relationships based on primate neocortex-to-brain size scaling. Observational research (such as analyses of personal social networks and card-sending exchanges) has reported mean network sizes clustering around 125 to 153. However, the empirical and statistical validity of 150 as a cognitive ceiling remains debated; modern phylogenetic re-analyses of primate and human group-size datasets found wide 95% confidence intervals (e.g., 2–336 and 4–520), indicating substantial uncertainty in deriving a precise cognitive limit.

1:11:54needs contextmoderateWhy I Stopped 'Biohacking' and Started Living | Ben Greenfie

Consuming evening carbohydrates triggers a serotonin and melatonin response.

"I'll have like 250 to 350 grams of carbs at night, which is great because you sock away a little bit of liver glycogen and muscle glycogen for a great workout the next morning. So with you get that serotonin melatonin response." (said at 1:11:54)

Consuming carbohydrates can stimulate insulin secretion, which promotes the uptake of branched-chain amino acids into muscle tissue and increases the ratio of free tryptophan to large neutral amino acids in the blood. Because tryptophan competes with these amino acids to cross the blood-brain barrier, this shift can facilitate brain tryptophan uptake and subsequent serotonin and melatonin synthesis. However, systematic and narrative reviews note that this mechanism is highly sensitive to macronutrient composition—it is largely blunted by even modest amounts of co-ingested protein—and the actual magnitude of evening melatonin elevation from dietary carbohydrates remains uncertain in real-world diets.

1:12:55needs contextmoderateWhy I Stopped 'Biohacking' and Started Living | Ben Greenfie

Digestive bitters can act as glucose disposal agents before a meal.

"I have some bitters with dinner, which kind of act as glucose disposal agents." (said at 1:12:55)

Administration of bitter tastants prior to a meal can lower postprandial blood glucose levels by activating gastrointestinal bitter taste receptors, which stimulates insulin and glucagon-like peptide-1 (GLP-1) secretion. A randomized controlled trial in healthy men demonstrated that pre-meal intragastric administration of the bitter tastant quinine significantly reduced postprandial glycemic response and stimulated insulin release. However, while the physiological mechanism for bitter receptor activation in glucose regulation is supported by research, evidence is largely based on specific bitter tastants or purified compounds rather than standardized commercial dietary 'digestive bitters.'

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