Dr. Kara Fitzgerald

Dr. Kara Fitzgerald

Aging is the biggest risk factor for ALL chronic diseases

If we can target aging itself, the potential benefits are enormous

Advancements in longevity science are creating new, exciting possibilities

Globally, chronic disease is the leading cause of morbidity and mortality, and the biggest contributor to reduced productivity and quality of life.

You might be surprised to learn that the greatest risk factor for chronic disease is AGING itself. Even ahead of smoking, high blood pressure, and obesity!

But up until recently, it wasn’t thought that we could do much about our pre-programmed aging trajectory, other than practicing basic, healthy living.

Now, we are able to measure biological aging, and scientists – myself included – are learning how to positively influence it


Turning back the hands of time

One of the keys to unlocking these possibilities is in the new study of epigenetics – the layer of “code,” written on top of your genes that regulates their expression and therefore the behavior of your cells and organs. Within this epigenetic code lies the instructions for your aging journey. It’s measurable. And, most importantly, it’s proving to be changeable.

By targeting our internal epigenome, we have the potential to delay chronic illness–and its associated prescription drugs, surgical procedures, reduced productivity, and poor quality of life–and actually slow or reverse biological aging.

Researching age reversal in humans

In 2018 we embarked on a first-of-its-kind human clinical study in men looking at the effect of epigenetically-targeted diet and lifestyle practices on gene expression and biological aging. 

What we discovered far exceeded our expectations. In only 8 weeks, our study participants became on average 3.23 years biologically younger than our control group.

In 2021, we conducted a follow up case series in women using a similar 8-week intervention. This time, our participants averaged a 4.60-year biological age reduction. 


Access the research:

Aging, 2021 – Potential reversal of epigenetic age using a diet and lifestyle intervention: a pilot randomized clinical trial

Aging, 2023 – Potential reversal of biological age in women following an 8-week methylation-supportive diet and lifestyle program: a case series

Older and younger woman

These findings suggest that:

  • We can change gene expression
  • We can change our rate of aging
  • We can live longer, healthier lives.

Do you know how old you are, really?

Younger You Book


This subjective biological age self-assessment (BASA) questionnaire is a useful guide to show you what you’re already doing right and where you can improve. To find your bio age score (in years), simply answer the questions in this quiz and follow the directions at the end of the questionnaire to calculate your score.

When you complete the quiz you’ll also receive four FREE bonus video shorts – my conversations with experts in the field of functional medicine and longevity, who share their tips for staying healthier for longer.

About Dr. Kara Fitzgerald

Dr. Fitzgerald is engaged in clinical research on functional longevity and epigenetics using a diet and lifestyle intervention developed in her virtual and in-person functional medicine clinic. She is the author of Younger You: Reduce Your Bio Age and Live Longer, Better, a ground-breaking work detailing her research and tools for reversing biological age. So far, participants in her first controlled clinical study reduced their biological age by 3.23 years, and in her second case series study by 4.6 years. Dr. Fitzgerald is on faculty at the Institute for Functional Medicine (IFM), and has authored several peer-reviewed scientific papers and textbooks. She regularly lectures internationally and hosts the podcast New Frontiers in Functional Medicine. She received her doctorate in naturopathic medicine from the National University of Natural Medicine in Oregon.


Join our email list to receive carefully, selected content and get instant access to a special gift with practical tips from longevity experts to help you live longer, better.