Eat for the body you actually have.
No single diet wins for everyone. What moves performance and longevity is food quality, enough protein, the right energy balance, and proof that it works for you. Here is what the evidence supports, what to skip, and how to find your own answer.
- ✓ Evidence-graded
- ✓ Anti-dogma
- ✓ Test it on yourself
The reality
The gap between eating and eating well.
Most people argue about diets while the real damage hides in the food itself. The modern plate has been quietly reformulated over a century, and your body is keeping the receipts.
Your fat is not what it was
Linoleic acid intake rose almost 15-fold between 1865 and 2008, from about 2 grams a day to 29, as seed oils replaced traditional fats across the food supply (Outliyr: toxic seed oils).
It bioaccumulates for years
The linoleic acid stored in human body fat climbed from 9.9% in 1960 to 23.4% by 2008, so the oils you ate years ago are still shaping your physiology today (Outliyr seed oil research).
Sugar is the silent default
Most people now eat roughly five times more sugar than the consensus considers healthy, a constant metabolic tax that no clever diet label cancels out (Outliyr: how to biohack your diet).
How to think about it
Stop picking a diet. Start fixing the inputs.
Performance and longevity are downstream of a few inputs you control: food quality, enough protein, an energy balance that fits your goal, and a metabolism flexible enough to handle real food. Get those right and the label on the diet barely matters.
Quality before macros
Whole, nutrient-dense food, enough protein, and cutting the industrial oils and added sugar move health more than any macro split. These are the inputs that compound, and they work on every diet.
Strongest impact · Diet-agnostic
Score it before you buy it
Run every supplement, peptide, and protocol through BioHarmony, our framework for rating any intervention on evidence, effect size, safety, and cost, so marketing does not earn a place in your kitchen.
Downsides weighted as heavily as upsides
No diet wins for everyone
Keto, carnivore, Mediterranean, and a prometabolic plate all work for some people and fail others. Genetics, gut, activity, and goals decide. Treat any diet claim as a hypothesis to test, not a verdict.
Context over dogma
Assess, don’t guess
The most compelling nutrition research describes the average eater. The diet that transformed a study group may do nothing for you, and the influencer thriving on carnivore may have a metabolism nothing like yours. So if you decide to test something here, don’t guess whether it is working. Run a personal n=1 experiment in Outliyr, test it against your own baseline, and get a keep-it-or-drop-it verdict graded by how strong the evidence is for you specifically. That is the whole point of the platform: verification instead of description.
Start your free profile →Go deeper
Explore diet by sub-topic
Nutrition breaks into a handful of levers. Pick where you want to go deeper.
The complete diet system
How to build a way of eating around food quality, not dogma.
Start here → 🥩Protein, done right
Why most people under-eat it, and how much you actually need.
Get the targets → 🛢️Seed oils & food quality
The industrial fats quietly reshaping the modern body.
See the evidence → ⏱️Fasting & meal timing
What fasting really does, and when it helps or hurts.
Learn the rules → 🔥Prometabolic eating
The bioenergetic, Ray Peat-inspired case for fueling your metabolism.
Explore the model → 🔄Metabolic flexibility
Train your body to burn both fuels and stop riding the blood-sugar rollercoaster.
Get flexible →Scored, not marketed
BioHarmony scores for diet & nutrition interventions
Each one rated on evidence, effect size, safety, and cost. Tap any to read the full report.
Field notes
Diet pro tips
The high-impact principles I come back to, distilled.
Get the foundation right
- Prioritize food quality first. Whole foods, pastured animal products, and ripe produce beat any clever macro split on a base of junk.
- Hit your protein. Most people under-eat it. Roughly one gram per pound of your ideal weight is a sane starting target for body composition.
- Cut the industrial oils and added sugar before anything else. They are the two inputs doing the most quiet damage.
- Read labels. Hidden sugars and seed oils hide under dozens of names, even in foods marketed as healthy.
- Don’t fear a diet because it is unfashionable. Judge it by what it does to your energy, labs, and body, not its reputation.
Tune it to your body
- Match your energy to your goal. Fat loss, maintenance, and muscle gain are different intakes. There is no single right number.
- Build metabolic flexibility so you can burn both fat and carbs without crashing between meals.
- Use fasting as a tool, not a religion. It helps some people and harms others, especially the under-fueled and highly active.
- Reach for boring, evidence-backed supports first: protein, electrolytes, magnesium, and omega-3 before exotic stacks.
- Track a baseline before you change anything, then judge any diet on multi-week trends in how you look, feel, and perform.
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The deep dives readers use most, organized by where you are.
Fundamentals
Dietary approaches
Diet & nutrition: common questions
What is the best diet for longevity?
There is no single best diet for everyone, and anyone who tells you otherwise is selling something. The patterns that show up across long-lived populations share traits more than a brand name: mostly whole foods, adequate protein, minimal industrial oils and refined sugar, and an energy intake that matches activity. Mediterranean, prometabolic, and lower-carb approaches can all work when they are built on real food. The honest answer is to start from those shared principles, then test a specific approach against your own labs, energy, and body composition rather than copying someone else’s results.
How much protein do I actually need?
Most people eat too little, especially as they age and during fat loss. A practical starting target for an active person is roughly one gram of protein per pound of your ideal body weight, spread across the day. Older adults and those in a calorie deficit benefit from the higher end to protect muscle. The exact number is less important than consistently hitting a sufficient amount from quality sources, then adjusting based on how your strength, recovery, and body composition respond over a few weeks.
Are keto or carnivore diets worth trying?
They can be, for the right person and the right goal. Keto and carnivore reliably cut processed food, sugar, and seed oils, which is often where the early wins come from. Some people feel dramatically better, while others lose performance, sleep, or thyroid function over time. They are tools, not identities. Treat either one as a time-boxed experiment, track how you actually feel and what your labs do, and keep it only if the data on you specifically supports it. Use the BioHarmony scores above to weigh individual interventions within those diets.
Are seed oils really that bad for you?
The concern is real even if the internet overstates it. Linoleic acid intake has risen roughly 15-fold over the last century as industrial seed oils replaced traditional fats, and that fat bioaccumulates in your body for years. High intake of oxidized, refined omega-6 fats is plausibly linked to inflammation and metabolic problems. The practical move is simple and low-risk: cook with stable fats like butter, ghee, tallow, and olive oil, and cut the fried and ultra-processed foods where these oils hide. You do not need to fear every trace to benefit from reducing the load.
Does meal timing and when I eat matter?
It matters less than total intake and food quality, but it is not nothing. For most people, front-loading calories earlier in the day and avoiding large meals right before bed supports better blood sugar and sleep. Time-restricted eating can help with adherence and metabolic markers for some, while it backfires for the highly active or under-fueled who then under-eat. Get your total intake, protein, and food quality right first. Treat timing as a fine-tuning lever you test on yourself, not the main event.
Do I need to count macros or calories?
Not forever, but counting for a few weeks is one of the most useful things you can do. Most people are surprised by how much or how little they eat, and especially by how little protein they get. Track honestly for a short stretch to calibrate your eye, then transition to portion awareness and consistency. If you have a specific body-composition goal that has stalled, going back to precise tracking temporarily is the fastest way to find the leak. The goal is awareness, not a lifetime of weighing food.
How much sugar is too much?
Most people now eat several times more added sugar than is healthy, often without realizing it because it hides in sauces, drinks, and foods marketed as wholesome. The issue is less a single magic threshold and more the constant metabolic load of refined sugar displacing nutrient-dense food and spiking blood sugar all day. Whole-food sources of carbohydrate like fruit, tubers, and honey behave very differently from refined sugar in processed products. Read labels, cut the liquid sugar first, and let real food carry most of your carbohydrate intake.
Should I take supplements or just eat well?
Food first, always, but a few supplements earn their place when diet alone falls short. Protein powder, electrolytes, magnesium, omega-3, and vitamin D with K2 are the boring, evidence-backed options most people benefit from. The rest of the supplement aisle is mostly marketing, and dose, form, and quality matter enormously. Run anything you are considering through the BioHarmony scores above, which rate each intervention on evidence, effect size, safety, and cost, then test the keepers against your own baseline rather than assuming they work.
