Bryan Johnson vs Ray Peat

2025-01-15

I think whether @bryan_johnson or Ray Peat is right about metabolism is one of the most interesting questions in longevity & human biology. There are many health communities but very few of them are actively innovating at any point in time, and both Bryan and the peaters are legitimately generative; new ideas every month if not every week

They also take absolutely opposite positions on some crucial topics, which suggests at least one of them is wrong and we’re all going to learn some new stuff if we pay attention. A lot of people have asked about this; the following are what I see as the core differences.

Quick context: Bryan is a tech founder known for trying to live forever, carefully tracking his biomarkers, and creative health interventions (though he’s actually trying to start a new religion); Ray Peat was a bioenergetics researcher focused on metabolism & health.

Bryan and Ray broadly agree on some things, e.g. the importance of sleep & fun, avoiding environmental toxins & food additives, that the defaults of modern life are often bad. Bryan is mostly vegan (save for collagen supplementation), which he says is a mix of (a) animal-based products not being necessary for health and (b) a moral/aesthetic position.

Peat died at 86 — a briefer life than Bryan’s target, but extremely respectable given that Peat’s thyroid was destroyed by a medical accident (radiation from a miscalibrated flouroscopy) when he was a child.

Finally, there’s no “Ray Peat diet” because Peat didn’t think there was a one-size-fits-all solution, but he did offer principles that he believes deeply inform & constrain the search for healthy-for-you foods.

Anyway, to the disagreements — the most interesting differences I see:

1. Total nutrients & ease of digestion vs nutrient-per-calorie

Bryan’s Blueprint diet is mostly vegan and broadly vegetable/legume based; peaters suggest an animal+fruit base, with dairy, eggs, & well-cooked vegetables and potatoes as tolerated.

Bryan’s position seems to stem from two hypotheses: first that meat/dairy are unhealthy in excess (due to e.g. saturated fat) and aren’t necessary for health, and second that “every calorie should fight for its place” — i.e. fruit has lots of sugar / empty calories, whereas vegetables are more nutritionally dense per calorie.

The peater rationale is that meat+fruit lack phytotoxins that downregulate the thyroid (cooking deactivates some but not all, and this is important) and that the nutritional profile of fruits, organ meats, and dairy especially is especially good for humans. And in general eating a high-calorie diet is actively good if you have an active metabolism (more on that below)

I think Bryan’s prediction is that peating will age people due to junk building up faster than normal due to the higher metabolism; the peaters predict Blueprint will age Bryan due to lower energy production leading to lower metabolic capacity, leading to idiosyncratic homeostatic deficits (more on this below)

2. Saturated fat

Bryan strongly believes saturated fat is the worst fat; peaters think it’s the best. Broadly speaking, Bryan seems to believe MUFA>PUFA>SFA whereas the peaters believe SFA>MUFA>PUFA.

Ray Peat was a primary origin for pushback against “seed oils” and wrote extensively about why the chemical structure of polyunsaturated fatty acids (PUFAs) are intrinsically unhealthy (due to the instability of the molecules) and lead to metabolic dysfunction; Bryan has written several detailed threads about why he believes the “seed oil” criticism isn’t supported by the data and why he believes saturated fat is more of a danger (though he prefers monounsaturated fat (MUFA) to polyunsaturated fat (PUFA), partly due to the chemical extraction technologies used to make PUFA).

Important to note here that cows are ruminants and the bacteria in their stomachs saturate the oils they eat; they can eat a high-PUFA diet and turn it into mostly saturated fat. This is not true for pigs, chickens, and humans — the oils they (we) eat mostly go directly into our cells as-is.

The peater oil tier list is something like:

S-tier: coconut oil, tallow, butter/ghee
A-tier: olive oil
B-tier: avocado oil, lard
F-tier: everything else
F-minus-tier: fish oil (fish in general is considered okay, but fish oil supplements are high in PUFA & probably oxidized: actively harmful)

If I had to guess the Bryan Johnson oil tier list, it’d be something like:

S-tier: olive oil (mostly MUFA), nuts (especially macademia, which is mostly MUFA), EPA/DHA/DPA (similar to fish oil but from algae, due to purity concerns / vegan preference — PUFA), seeds (PUFA)
B-tier: vegetable oils
C-tier: saturated fats

I think Bryan’s prediction is that peating will lead to more cardiovascular events; the peaters predict that the medium levels of PUFA that Bryan eats will slowly lead to an impaired metabolism (and in particular a fatty liver; Bryan’s latest tests do show a spike here). One near-universal anecdote from the peaters is that switching to low-PUFA makes one very resistant to sunburn. Whether this is “kinda cool but irrelevant” or “a very important thing that says much about the effects of PUFA vs SFA on the stability of cellular lipids” is an open question.

3. High vs low metabolic rate

Bryan is intentionally throttling his metabolism; the peaters try to maximize theirs. (Both think body temperature is a good proxy and proudly tweet temperature readings)

Bryan has experimented with calorie restriction and currently eats a ~10% caloric deficit (up from 20%); his rationale seems to be that (a) empirically, caloric restriction has produced substantial results in animal longevity trials, and (b) according to theory, reducing metabolism will reduce the byproducts of metabolism, which many longevity models (e.g. SENS, turn.bio) believe are substantially responsible for aging.

Ray Peat’s expectation is different: ”as energy flows through tissue, order accumulates” and “energy and structure are interdependent at every level” — Peat argues that we maintain structure through metabolism, and the more energy we have flowing through our tissues the more order-preserving and order-generating processes can be supported. I.e. life is powered by energy gradients and maintaining these gradients is crucial; aging happens as the machinery that powers these gradients degrades and the gradients become shallower.

An important Peat hypothesis here is the desirability of “metabolic uncoupling” — that mitochrondria have two modes of operation, coupled (efficient but dirty) vs uncoupled (inefficient but clean). Essentially, if mitochondria operation is “coupled” to energetic input, cells become very efficient at wringing every bit of energy out of food, but produce some unhealthy byproducts due to this optimization. Whereas if they’re “uncoupled” they care less about energetic efficiency and also ‘wastefully’ burn excess calories as heat, but this “waste” is relatively clean and produces fewer total byproducts.

In this view, insulin resistance happens when mitochondria lose their ability to handle large influxes of calories (i.e. their capacity for operating in an ‘uncoupled’ mode) and start to refuse to allow energy to enter the cell. Peat thought that PUFA was perhaps the biggest contributor to this loss of capacity, and the peater critique of Bryan’s approach to metabolism is it may lead to a more fragile metabolism in general; he may shift from avoiding extra calories by choice, to avoiding excess calories by necessity. (Of note, Bryan has historically been hypothyroid and iirc supplements thyroid — not a knockdown of his argument but relevant for people following his protocol)

The maximal point of departure between Bryan and the peaters may be sugar — Bryan lists it as a primary substance to avoid, whereas the peaters think it’s actively healthy — fruit is good not despite its sugar, but partly because of it. Honey is healthy; even white table sugar is healthy, as long as your metabolism is sufficiently uncoupled. https://x.com/takethiamine/status/1878335393218924759?s=61&t=5VQTNkNIZXWdL93vB-TH3A

Cards on the table, I think Bryan is demonstrably healthy, but I agree with Peat on these three topics and I worry Bryan’s in the process of getting himself into metabolic trouble (perhaps due to a preference for a vegan solution, and perhaps animal-based diets being right-coded / traditional masculinity coded). That said I think Bryan’s doing an amazing public service, I’m very grateful he exists and is doing what he’s doing, and I think it’s an incredible aesthetic.

Something @nickcammarata has mentioned is we really need a Peat version of Bryan Johnson; someone charismatic who extensively tracks peating-inspired biomarkers so we can get some parallax on Bryan’s progress.

Diet is a huge topic and I haven’t touched on many core peater topics, e.g. calcium/magnesium/thyroid/aspirin, high-dose thiamine, iron overload, CO2, estrogen dominance, prolactin, serotonin as a stress hormone, the role of sunlight, starch & persorption, progesterone & pregnenolone, coffeemaxing, the carrot salad, etc… maybe in the next Peat thread. As @natelawrence_ has suggested, a good place to start with any health topic is just searching “[topic] ray peat”

Resources

Blueprint protocol/diet (Bryan’s core protocol): https://blueprint.bryanjohnson.com/pages/blueprint-protocol

Bryan’s threads on vegetable oils (“seed oils”):

Ray peat articles: https://raypeat.com

Ray Peat on vegetable oils https://raypeat.com/articles/articles/unsaturated-oils.shtml

Ray Peat obituary by @LandsharkRides: https://im1776.com/2022/12/14/ray-peat-obituary/

Peating & peat-adjacent accounts

Apologies if I missed you!

@anabology — very smart, careful & generative thinker, always doing interesting things

The anabology honey diet: a fascinating protocol for losing weight & maintaining high energy with extreme amounts of sugar https://longestlevers.com/fat-loss/honey-diet.html

Example anabology honey diet report: https://x.com/integratedalex/status/1878185328822862304?s=61&t=5VQTNkNIZXWdL93vB-TH3A

@pikeypilled — general peating, dangers of iron overload

@TakeThiamine — thyroid, thiamine, general peating

@JulianaLung — entrepreneurial peater building @verasaltco

@celestialbe1ng — Eastern European feminine peater vibes, good supplement list, veteran of the Great Foid War of 2024

Modern challenges to metabolism https://x.com/celestialbe1ng/status/1862296828328268205?s=61&t=5VQTNkNIZXWdL93vB-TH3A

Peating supplement list https://x.com/celestialbe1ng/status/1876650008415445116?s=61&t=5VQTNkNIZXWdL93vB-TH3A

@haidut and @dannyroddy — great podcast history on peating

@natelawrence_ — OG peater, general peating & thyroid

How to improve thyroid function https://x.com/natelawrence_/status/1878187204201033789?s=61&t=5VQTNkNIZXWdL93vB-TH3A

Intro to Ray Peat’s thinking https://x.com/natelawrence_/status/1680974204101877761?s=61&t=5VQTNkNIZXWdL93vB-TH3A

@T3MaxxiAlt — thyroid supplementation, general metabolism

@lowmegatron — peating neurochemistry; serotonin critic

@BradCohn — OG peater, trybloo.com

@LandsharkRides — OG peater and immaculate poaster, upstream of most of the internet

@cynomaxxx @cynomel @RayPeatHeadShop @fishdrinkmilk @PeatPill @Outdoctrination @CO2_O2_Synergy @Thermobolic — peating (all different all good)

@KruseYouri — evils of fish oil

Peat-adjacent

@paulsaladinomd — low-toxin animal-based diet

Saladino on seed oils: https://x.com/paulsaladinomd/status/1729606439524548968?s=61&t=5VQTNkNIZXWdL93vB-TH3A

@jessicaalanas — environmental toxins, peptides

@BioavailableND — environmental toxins, fertility

@SolBrah — believes some crazy things but does so in a beautiful way; good vibes, often peat-adjacent

@VanceE — high-quality methylene blue @ merakimedicinal.com

@Helios_Movement — lots of great peat-compatible content although some tyranny-of-small-differences feuds with peaters

Sample diet for good micronutrient coverage https://x.com/helios_movement/status/1878807145900392653?s=61&t=5VQTNkNIZXWdL93vB-TH3A

@AbudBakri — light therapy, good takes

@ChrisMasterjohn — excellent original research on nutrition; separate generator from the peaters but often gets to the same places

Historically there was a big divide in peating between “Mexican peating” (Ray himself) which prioritized sunshine, low stress rural life, and natural high-sugar foods, vs “Bulgarian peating” (e.g. @haidut @landsharkrides) which prioritized metabolically-relevant research chemicals for dealing with high-stress faster-paced urban environments. I think there might be another speciation event just starting

Bonus

Carrot Salad Ballad: https://x.com/banay_john/status/1789807590551191578?s=61&t=5VQTNkNIZXWdL93vB-TH3A

Peating not for the weak: https://x.com/schizo_freq/status/1792874427794801082?s=61&t=5VQTNkNIZXWdL93vB-TH3A

Originally posted on X/Twitter: Bryan Johnson vs Ray Peat.