Compare experts › Gary Brecka vs Jason Fung

Gary Brecka vs Jason Fung

Gary Brecka (wellness entrepreneur (not a doctor)) and Jason Fung (physician, kidney specialist) side by side: how they train, eat, supplement and sleep, how strong the evidence is, and how to build a plan from either or both.

Build a plan from both See the protocols

Words explained (10)

Zone 2: Steady cardio at a pace where you can still talk in full sentences, but not sing.
Intervals: Short hard efforts with easy recovery in between, such as 30 seconds fast, 90 seconds slow.
4 × 4: Four rounds of 4 minutes hard with 3 minutes easy in between. Also called Norwegian intervals.
Loaded carry: Walking while holding something heavy, like shopping bags or dumbbells.
Mobility: Moving your joints freely through their full range.
Creatine: A well-studied supplement that supports strength and muscle.
Omega-3 (EPA, DHA): Healthy fats found mostly in oily fish such as salmon, herring and sardines.
Time-restricted eating: Eating all your meals within a set window of the day, for example 8am to 6pm.
Mitochondria: The parts of your cells that turn food and oxygen into energy.
MTHFR, methylation: A gene and the chemical process it helps with. The common variants are very frequent, and testing them is not recommended for most people.

At a glance

Measure	Gary Brecka	Jason Fung
Background	Wellness entrepreneur (not a doctor)	Physician, kidney specialist
Training split	20% strength · 55% aerobic · 5% intervals · 20% mobility	45% strength · 35% aerobic · 12% intervals · 8% mobility
Signature habit	Sunlight, breathwork, cold	Fasting, less sugar
Protein	~30 g soon after waking	No fixed target
Training style	Morning rituals	Fasting
Overall evidence	Mostly weak	Mostly weak
Following	Instagram 3M · YouTube 63K	YouTube 1.5M

Training splits are our estimates from each expert’s published routine. Following checked October 2026.

The key differences

Fung puts more of the week into strength: about 45% against 20%.
Brecka puts more of the week into aerobic base (zone 2): about 55% against 35%.
Brecka puts more of the week into mobility and stability: about 20% against 8%.
In plans in their style, Brecka's hard sessions are 1-minute intervals; Fung's are 4-minute intervals (Norwegian 4 × 4).
We rate the overall evidence behind both protocols as mostly weak.
Supplements that go into a plan: Brecka, omega-3 fish oil, creatine monohydrate; Fung, none (food first). Prescription items and personal stacks stay out of every plan.
Only Brecka has a mobility or movement routine of their own.

Protocols side by side

Each line is rated for the evidence behind it. “Doctor only” items never go into a plan.

Training

Gary Brecka

About 30 minutes of low-intensity movement in the morning (part of the '30-30-30' idea he promotes)Strong evidence
Stay mobile and active every dayStrong evidence
Exercise while breathing extra oxygen (EWOT)Personal habit
Gives few specific strength-training targetsNote

Jason Fung

No specific guidance in what we reviewed.

Eating

Gary Brecka

About 30 g of protein within 30 minutes of wakingSome evidence
Avoid processed foods; eat whole foodsStrong evidence
Lower-carb or ketogenic plans for weight loss in some clients, guided by blood testsDoctor only

Jason Fung

Cut added sugar and refined grains; eat whole foods with natural fats.Some evidence
Stop snacking: three meals a day, then skip one meal a day.Personal habit
Eat within a shorter window of the day (time-restricted eating).Some evidence
Fasts of 24 hours (skipping two meals in a row) two or three times a week, as used in his clinic's programme.Personal habit
Longer fasts of several days; in 2016 he said fasts of up to a month were fine.Doctor only
For type 2 diabetes: no sugary drinks, fructose or processed food, and more natural fats.Doctor only

Supplements

Gary Brecka

Vitamin D3, ideally guided by a blood testDoctor only
Omega-3 fish oil in the morningSome evidence
Methylfolate and methylated B vitamins based on a methylation gene testPersonal habit
Hydrogen water tabletsPersonal habit
Creatine (sold under his brand)Some evidence
Peptides such as BPC-157 and TB-500 (he is a fan)Doctor only

Jason Fung

No specific guidance in what we reviewed.

Sleep & recovery

Gary Brecka

Morning daylight to set the body clockStrong evidence
Short daily cold water exposureSome evidence
Red light therapy bed, about 20 minutesPersonal habit
Hyperbaric oxygen and cryotherapy at homePersonal habit

Jason Fung

No specific guidance in what we reviewed.

Stress & mind

Gary Brecka

Wim Hof-style breathing: 3 rounds of 5–30 breaths, then a breath hold, always seatedSome evidence
Same routine at the same time each dayPersonal habit
Barefoot grounding outdoorsPersonal habit

Jason Fung

No specific guidance in what we reviewed.

Weak spots to know

Gary Brecka

He is not a medical doctor or a research scientist; McGill University's Office for Science and Society (Jonathan Jarry, 2025) called his expertise questionable and said the health interventions he points customers to run from unproven to pseudoscientific.
His MTHFR claims run against medical genetics guidance: the American College of Medical Genetics and Genomics has advised against routine MTHFR variant testing since 2013 (updated 2020).
Hydrogen water, grounding and red light are presented with more certainty than the research supports; the McGill review described hydrogen research as small and early, and grounding as pseudoscience.

Jason Fung

Red Pen Reviews scored The Obesity Code at 31% for scientific accuracy, and The Diabetes Code at 33%.
His central claim that calories do not matter is contradicted by controlled studies.
Much of his support comes from case reports, small older studies and his own clinic.

Build a plan from Brecka, Fung or both

Your free plan shows a week of gym sessions, cardio, a day of eating, supplements and mobility, fitted to your age, time and health.

Plan in Brecka's style Plan in Fung's style Mix both

Questions

What is the main difference between Gary Brecka and Jason Fung?

Their training split differs most in strength: Brecka about 20%, Fung about 45% (our estimate from their published routines). Brecka's signature habit is Sunlight, breathwork, cold; Fung's is Fasting, less sugar.

How much protein do Brecka and Fung recommend?

Brecka: ~30 g soon after waking. Fung: No fixed target.

Whose advice has stronger evidence?

We rate the overall evidence behind both protocols as mostly weak.

Do Brecka and Fung disagree?

Not directly in what we reviewed. Their differences are in emphasis: fung puts more of the week into strength: about 45% against 20%.

Can I combine Brecka and Fung?

Yes. In Build my mix you choose one expert per area, for example one for strength and another for eating. Your free plan shows the result straight away.

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Full sources are on each profile: Gary Brecka · Jason Fung. Reviewed October 2026.