If You're Looking to Improve Your Health and Age Well, Start Here
Your lifestyle reset: what actually matters and where to start
Let’s face it.
The world of health information has never been noisier.
Every day there’s a new trend, controversial take, or health hack claiming to be the answer.
But even when the information is accurate, knowing what to focus on first - and how to turn it into lasting habits - can feel just as overwhelming.
With the Longevity Code community growing so much recently, this felt like the perfect time to regroup and create a simple foundation we can all come back to before we dive deeper into the science over the coming months.
Today, we’ll cover:
🧬 The 7 biggest factors that influence longevity - and where to start with each one
🧠 How to use Longevity Code as your long-term healthy aging toolkit
✨ An exciting personal update
Whether you’re just starting out or years into your health journey, use this edition as a chance to reset and plant new seeds for your future health.
The 7 biggest predictors of longevity
Let’s start by reminding ourselves what longevity actually means.
Lifespan is the number of years you live.
Healthspan is the number of those years spent in good health - free from major disease and able to live independently.
Together, they shape your overall longevity.
To influence longevity, our focus needs to be on supporting the underlying biological aging process.
Many people think it’s mostly down to genetics.
But research suggests genetics explain only around 20-30% of differences in how long people live. [1,2]
That means many of the biggest drivers are things we can actually influence.
Here are 7 of the most foundational and impactful:
1) Smoking status
Perhaps the biggest modifiable predictor of longevity.
Smoking has clear causal links to cancer, cardiovascular disease, and neurodegenerative diseases.
On average, it shortens life by around 10 years (up to 25 years for heavy smokers). [3]
A powerful first step in caring for your longevity would be to stop smoking if you currently do.
2) Cardiorespiratory fitness
Your VO₂ max (a measure of how efficiently your heart and lungs deliver oxygen during exercise) is one of the strongest measurable predictors of longevity.
People with the highest fitness have about a 53% lower risk of dying early compared with the least fit.
Even moving from unfit to moderately fit can reduce the risk of early death by around 33%. [4,5]
Regular aerobic activity, such as brisk walking (where you feel slightly out of breath), is an effective way to improve this.
3) Healthy body weight
BMI (Body Mass Index) isn’t a perfect measure of health, but it can be useful when looking at trends across large populations.
Generally, the lowest health risks are seen in the leaner part of the healthy BMI range (18.5-22.4).
Health risks generally rise above 25, and a BMI of 35+ is linked with 7-9 fewer years free from chronic disease compared with people in the normal weight range. [6,7]
4) Relationship quality
Your regular catch-ups with loved ones aren’t just good for your mood.
The 80-year Harvard Study of Adult Development found that close, supportive relationships were the strongest predictor of long-term health and happiness - more than money or diet. [8]
Regular connection helps buffer stress and can positively impact immune function and brain health.
Quality > quantity.
5) Blood pressure
Blood pressure is the force of blood pushing against your artery walls as your heart pumps blood around your body.
High blood pressure often has no obvious symptoms, but over time it can damage blood vessels and increase the risk of heart disease, stroke, and dementia. [9]
Keeping your blood pressure in a healthy range is one of the most protective things you can do for your long-term health.
6) Diet quality
Definitely the most debated area of health online.
But the research is actually much simpler.
The biggest benefits consistently come from eating more whole, minimally processed foods and fewer ultra-processed foods.
People eating the most UPFs have around a 20% higher risk of early death. [10]
Find an approach that works for you and that you can sustain. At the core, prioritise fruit, vegetables, legumes, nuts, fish, quality animal protein sources, and plenty of fibre.
7) Sleep
In a large recent U.S. analysis of thousands of counties, insufficient sleep was the strongest behavioural predictor of life expectancy after smoking - stronger than diet or exercise. [11]
Sleep is when inflammation is regulated, DNA repair increases, immune function recalibrates, and the brain clears waste.
7-8 hours at consistent times (ideally aligned with your natural light-dark cycle) is one of the biggest longevity levers you can pull.
Forget the complicated protocols and expensive supplement stacks you’ve seen online. These are the foundations that move the needle most.
Grab a pen and paper, write down these 7 areas, identify where you could improve for each, and use today as your reset point.
Your healthy aging resource
Next, I want to show you how to get the most out of Longevity Code over the months and years ahead.
Starting this newsletter 18 months ago has been a huge learning experience - growing as a researcher while also learning how to effectively turn complex science into simple insights and practical tools you can actually use.
Every other Tuesday, the free newsletter will continue to bring you evidence-backed insights from the world of healthy aging and prevention.
For those who want to go deeper, the paid newsletter (every Tuesday) breaks down the research into practical strategies and lifestyle frameworks you can apply every week to support your health and longevity.
Personal update
I’m excited to say I’ve recently gone full-time as a science communicator, alongside my doctoral research exploring the biology of aging and prevention.
This newsletter and my social platforms are now my main focus and source of income.
If you’d like to help fund this research and support my overall mission, becoming a paid member would mean a lot.
Thanks for reading!
For now, take some time to reflect on the 7 foundations we’ve discussed and think about where you can make small improvements.
See you in your inbox next Tuesday.
— Ollie
Disclaimer: This post provides educational information based on scientific research and is not medical advice. It does not establish a doctor-patient relationship. Always consult a qualified healthcare professional before making lifestyle changes, addressing medical conditions, or starting new treatments.
Number 4 jumped out at me. I've got players in their 60s and 70s who show up to my Meetup group three times a week, and half of what they're getting isn't the exercise, it's the group of people they see every session. Some of them have told me straight out that pickleball is the reason they talk to other humans regularly since retiring.
The VO2 max point tracks with what I see on court too. My students who've stuck with it for a couple years move differently than when they started, lighter on their feet, less winded after a long rally. I don't think most of them are thinking about longevity when they show up, they just want to beat their friend in the next game, but the byproduct is exactly what you're describing.
Curious how you'd rank these 7 if someone could only tackle two at once. Would you push sleep and fitness first, or start with something else?
Great breakdown. Ultra-processed foods are bad in so many ways. Not only do they increase mortality like you mentioned, a study this year that I wrote a breakdown on linked them to fat infiltration in our muscles, regardless of BMI or physical activity (Akkaya et al., 2026).
And that decreased muscle quality is itself linked to weaker muscle strength, greater knee pain, and increased frailty.
So worse quantity and quality of life.