The Letters

What My Dissertation Was Supposed To Be About

By Seçil Sayhan, MSc Clinical Health Psychology & Wellbeing3 min readAugust 18, 2026

What’s in this article

  1. The pattern
  2. The mechanism behind it
  3. What to do with it
  4. The bigger picture
  5. Frequently asked questions

my dissertation was supposed to be about food.

The pattern

I registered a question about nutrition and got an answer about perception. Seventy-four adults, a model that ignored every supplement in it, and the age comparison I have not stopped thinking about since 2022 — including the part where I argued against my own finding.

The mechanism behind it

My master's dissertation was supposed to be about food.

Eating habits, nutrient deficiency, supplements — what people put into their bodies to manage stress and anxiety. That was the registered question, and for months it was the one I believed in. Seventy-four adults, nineteen to sixty-three: what they ate, what they took, the state of their health, and how anxious they had been over the previous two weeks.

The supplements predicted nothing. Neither did whether the person was, medically speaking, healthy.

One variable in the model predicted their stress, and it was how they read their own life. Twelve questions about what someone believed about their life and their health. That score moved, and the anxiety moved with it.

The finding I still turn over is the age comparison. The older participants had more health problems and less anxiety than the physically healthy young ones. Worse bodies, quieter minds.

Seventy-four people measured at a single moment settles nothing about which direction the relationship runs, and I wrote a full section arguing against my own result. That section is still the most honest thing I have put my name on.

But I have built everything since on the possibility that it runs the way the data pointed — that a life is not made well by what gets added to it, and that the thing worth defending is a person's reading of their own days.

Which is why I now build systems that take the work off people rather than programmes that ask more of them.

What to do with it

eating habits, deficiency, what people take to feel less wrecked. that was the question i registered, and for months it was the question i believed in. seventy-four adults, nineteen to sixty-three, all of them telling me what they ate, what they took, what their body was doing, and how anxious they had been for the last two weeks.

the supplements predicted nothing. neither did whether the person was actually, medically healthy.

one thing in the model predicted their stress, and it was how they read their own life. twelve questions about what they believed about their life and their health. that score moved and the anxiety moved with it.

the part i still turn over: the older group had more health problems and less anxiety than the physically healthy young ones. worse bodies, quieter minds.

seventy-four people at one moment in time settles nothing about which direction it runs. i wrote a whole section arguing against my own finding, and it is still the most honest thing i have put my name on.

but i have built everything since on the possibility that it runs the way the data pointed. that a life is not made well by what you add to it, and that the thing worth protecting is a person's reading of their own days.

that is what all of this is. protect the reading. give the rest to the machines.

comment PROTOCOL and i'll send you what the dissertation actually found — free.

The bigger picture

my dissertation was supposed to be about food. eating habits, deficiency, supplements — what people take to handle stress.

seventy-four adults, nineteen to sixty-three, telling me what they ate, what they took, what their body was doing, and how anxious they had been for two weeks.

the supplements predicted nothing. neither did whether they were actually healthy.

the thing that predicted their stress was how they read their own life. and the older group, carrying more health problems, was less anxious than the physically healthy young ones.

seventy-four people at one moment settles nothing about direction — i wrote a section saying exactly that. i have still built everything since on the possibility that it runs that way.

my dissertation was supposed to be about supplements.
Run the numbers on your own week.

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Frequently asked questions

What is the main idea of "What My Dissertation Was Supposed To Be About"?

A study designed around eating habits and supplements returned a result about how people read their own lives — and the honest limits of a finding I have built a company on.

my dissertation was supposed to be about food. eating habits, deficiency, supplements — what people take to feel less wrecked. seventy-four adults, nineteen to sixty-three. the supplements predicted nothing. neither did whether they were medically healthy. the thing that predicted their stress was how they read their own life. and the older group, with more health problems, was less anxious than the healthy young ones. seventy-four people at one moment proves nothing about direction, and i wrote a section saying so. i have still built everything since on the possibility that it runs that way?

my dissertation was supposed to be about supplements.

How do you actually apply this?

Start with the Life Audit at marsa.ai/life-audit — free, and it turns this piece into a concrete first step.

Is this about willpower or systems?

Systems. Willpower is finite and unreliable; the durable lever is changing the system, the environment, and the defaults underneath the behavior.

Who is this for?

Founders, operators, and anyone trying to perform and live well in the AI age — the science applies whether it moves a person, a market, or a machine.

Where can I go deeper?

Start with the free protocols at marsa.ai. Every claim here draws on the clinical literature — see the full bibliography at marsa.ai/research.

About the author

Seçil Sayhan is the founder of MARSA. She spent a decade on one question: what makes a person thrive, instead of just keeping going. Her research tested the obvious answers — nutrition, supplements, physical health — and none of them predicted it; what predicted it was how someone read their own life. Then she built a company of her own and met the same problem from the inside, which is why MARSA has two halves: machines that take the work which repeats, and the training for the person those hours come back to. BA Business Management · MSc Clinical Health Psychology and Wellbeing · Diploma in Neuroplasticity · Lifestyle Medicine, Harvard University. Every method traces to a public bibliography of 190+ peer-reviewed sources: see the research.