The Path to 150M+ Daily Roblox Users, Ketogenic Therapy for Brain Health, and More — CEO of Roblox

David Baszucki joins Tim Ferriss for a wide-ranging conversation that opens with his family's deeply personal story: his son Matthew's 8-9 year struggle with bipolar disorder through college, hospitalizations, and homelessness, which finally improved on a ketogenic diet after 20-plus failed medications. They go deep on the mechanisms and practicalities of ketosis, including ketone monitoring, sleep, breath holds, exogenous ketones for Alzheimer's relatives, and ketosis resolving Tim's post-Lyme symptoms. The second half pivots to Roblox: its scale, the pivotal decision to build the Robux digital economy, mobile/3D bets, creator-revenue philosophy, copycat games, child safety, and AI. Baszucki frames much of his strategy around recognizing technological inevitabilities and playing the long game.

• After 20-plus medications failed over 8-9 years, Baszucki's son saw progress on a ketogenic diet within 3-4 weeks, which Baszucki calls 'a miracle' and the catalyst for the family's whole metabolic-health mission.
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• In December 2017 his son ran away full-blown manic, flushed his meds, streamed himself on social media, bused to San Diego and slept in a lifeguard shack; Baszucki recounts an elaborate rescue tricking him into a hospital via a fake steak-dinner and hand-injury checkup.
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• On a family trip to Mexico, avocados carried more carbs than expected and nudged Matt out of ketosis within days, bringing back manic symptoms; switching to just fish and butter popped him right back in, showing how tight the correlation is.
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• Roblox had great user/hours growth but lagging revenue under an old $5/month membership model; the team eventually committed to building a full Robux digital economy and knew within four hours of shipping that it worked.
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• Within four hours of launching the Robux economy, 22 of the top 100 creators had already integrated Robux features and users were already buying and spending, confirming the bet.
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• Baszucki says one of Roblox's best decisions was optimizing creator revenue over company profit, leaning cash back to developers rather than being a 'ridiculously profitable company.'
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• By end of year, Roblox plans to use AI age estimation via phone cameras to know users' ages and cluster people by age, blocking communication between users of widely different ages.
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• Ketones are a 'more primitive' second energy pathway the body enters during fasting or very-low-carb eating; Baszucki ties bipolar symptoms to the brain not getting consistent energy amid glucose spikes and crashes.
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• Matt's diet is under 20g of carbs per day and higher in fat than protein; Baszucki notes a quarter of a Coke has roughly 20g of carbs.
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• Continuous ketone monitors (CKMs) are sold in Canada but not yet approved in the US; Baszucki jokes he's in a 'smuggling ring' bringing them across the border.
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• After Wim Hof-style breathing at roughly 3 millimolar ketones, Ferriss extended a breath hold from about 45 seconds to 2 minutes 50; on day nine of a 10-day fast in a hyperbaric chamber he reached 9 minutes.
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• Ferriss gives Alzheimer's relatives 25-30 mL of BHB exogenous ketones and sees noticeably longer sentences and improved verbal acuity within 20-30 minutes; Alzheimer's is sometimes called 'type 3 diabetes.'
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• Ferriss credits 3 weeks of strict ketosis with resolving his post-Lyme cognitive symptoms, and reports a 4-5 out of 5 success rate with friends' documented Lyme cases.
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• Roblox has about 120 million daily users, roughly 9 billion hours of engagement per month, peaks over 40 million concurrent users, and accounts for about 3% of all gaming worldwide.
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• Roblox creators earned more than $1 billion in the past year, with thousands able to make a living and at least thousands earning over a million dollars.
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• Roblox gives every employee a CGM and labels all office snacks on two axes (whole-food and 'good energy'), inspired by Casey Means' book.
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• Baszucki's billboard message is 'Feed your head' (a Surrealistic Pillow reference), and he closes recommending heavy cream in coffee as an easy entry to ketosis.
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