Book Review: Outlive
Peter Attia, MD on fighting the "Four Horsemen" of chronic illness
Dear Readers,
Believe it or not, I don’t have a burning desire to live as long as possible. My background in veterinary medicine makes me prioritize quality of life over quantity. So when I first heard about Outlive, I wasn't particularly interested. However, my wife started reading it and suggested it was right up my alley, so I gave it a chance.
I'm glad I did!
Within a few pages, it became clear that the title Outlive is a bit of a misnomer; the book focuses as much on maintaining a good quality of life in your later years as it does on longevity per se. Initially skeptical, I was convinced by the end to implement some of Attia's strategies for a healthier lifestyle. Today, I’ll walk you through the book’s claims, compare them to current research (including for pets), and address some criticisms.
—Eric
Who is Dr. Peter Attia?
(…and why do I care what he thinks?)
Before listening to anyone’s claims, I always consider their background and qualifications. Dr. Peter Attia’s credentials are impressive: undergrad degree in applied math and mechanical engineeing, Stanford M.D., general surgery residency at Johns Hopkins, and a surgical oncology fellowship at the National Cancer Institute. Despite his skill and accolades, he became disillusioned with medicine, frustrated at how many of his cancer patients died despite heroic efforts, and he left practice for several years.
During his hiatus from medicine, Dr. Attia worked as a consultant focusing on quantitative finance and risk management. This experience later informed his preventative medicine approach, emphasizing a cost/benefit analysis of any intervention. He eventually returned to medicine and founded a bespoke primary care practice called Early Medical. Besides his medical practice, Dr. Attia is a prolific content creator with a newsletter, The Drive podcast, and his book, Outlive.
I find Dr. Attia credible because he is essentially the opposite of the many “Red Flags of Quackery” I previously wrote about. He…
✅ … has relevant scientific training and medical experience
✅ … is transparent about the pros and cons of various interventions
✅ … provides tons of context around his findings, linking & critiquing studies
✅ … does not write in an inflammatory or conspiratorial manner
✅ … happily changes his mind in response to new information
✅ … is not opposed to medications, but also does not rely primarily on them
✅ … doesn’t do ads or sell supplements
Medicine 3.0
How would I sum up Outlive for people who are too busy to read this post, let alone the book? It essentially boils down to one graph:
“Lifespan” measures how long someone lives, while “Healthspan” indicates their level of function, with 100% being the peak performance of one's teens and 20s, and decreasing from there.
The “No Intervention” line represents the natural course of untreated diseases, which he considers “Medicine 1.0,” since for most of human history, medical care was ineffective quackery. Modern medicine, or “Medicine 2.0,” excels at treating acute conditions like broken bones and bacterial infections but poorly manages chronic illnesses, often adding a few extra years without significantly improving quality of life.
“Medicine 3.0” is Dr. Attia’s term for a proactive approach emphasizing early and aggressive prevention to combat the major killers of the developed world: heart disease, diabetes, cancer, and Alzheimer’s. This idea is not mere wishful thinking. Studies indicate that succumbing to these diseases early is not inevitable; some people develop them much, much later in life, referred to as “compression of morbidity”. Note how these figures closely match the conceptual diagram above:
The “Four Horsemen” of chronic disease
Dr. Attia refers to heart disease, diabetes, cancer, and Alzheimer’s as the “Four Horsemen” of aging and chronic disease, and the first third of Outlive is devoted to understanding their development and progression. Several of them hold personal significance for me, as I have a family history of heart disease and diabetes, including a grandparent who sadly died of a heart attack before I was born. Attia offers detailed yet accessible explanations of key problems like insulin resistance, fatty liver disease, and plaque build-up in vessels, and how a wayward cell becomes cancerous. Like Atul Gawande and Siddartha Mukherjee, he is an excellent storyteller, weaving in fascinating science history anecdotes like the discovery of rapamycin in soil fungus on Easter Island. Even though I have a medical background and a PhD in cancer biology, I still found myself learning new details.
The rest of the book is devoted to strategies and tactics to combat the “Horsemen.” He delves into the pros and cons of simple caloric restriction, different types of fasting, and specific dietary guidelines, emphasizing the necessity of finding a sustainable long-term eating plan. Attia debunks common nutritional myths and highlights the significance of maintaining muscle mass and balance through regular exercise to prevent falls in old age. His recommendations span various types of cardio, strength training, and flexibility exercises, supplemented with detailed diagrams and videos.
In addition to physical health, Attia underscores the critical role of sleep in cognitive function and overall well-being, sharing his personal journey from exhausted workaholic to dedicated sleeper. In the last chapter, he tackles emotional health with a poignant account of his traumatic childhood and mental health struggles during the COVID-19 pandemic that resulted in inpatient treatment. Attia candidly discusses the detrimental effects of neglecting mental health and advocates for addressing emotional issues, regardless of whether they fit diagnostic labels. One of the most impactful lines in the book is a question from his therapist:
“Why would you want to live longer if you’re so unhappy?”
Counterpoints
Clearly, I’m a fan of Dr. Attia’s work and his book, but they are not above critique. Some of his recommendations are extremely aggressive, often involving non-standard biomarkers like ApolipoproteinB, Lp(a), continuous glucose monitors in non-diabetics, and genetic risk factor panels. While some of these practices—such as colonoscopies for people in their 40s—are becoming more mainstream, most insurance plans do not cover these tests. This highlights a core issue with this style of practice: it reflects the inequality in the US medical system, where the wealthy can afford the best care while others go without basic needs.
The effectiveness of this hyper-aggressive preventative approach on longevity remains an open question. Early intervention before long-term organ damage sets in makes intuitive sense for chronic diseases of aging, but there is scant data from clinical trials to prove it. While tightly managing LDL-cholesterol and other cardiovascular risk factors has shown promise for atherosclerosis, for other “Horsemen” like cancer and Alzheimer’s, the evidence is more speculative. High-quality, long-term studies are challenging due to the need for large cohorts and specific lifestyle adherence over decades. Despite Attia’s admirable shift of the longevity conversation away from supplements and “biohacking” towards lifestyle changes and emotional health, implementing his recommendations can be challenging. The book sometimes overlooks the socioeconomic barriers many people face in accessing quality nutrition, sleep, and exercise resources, often legacies of entrenched discrimination and inequality.
What about our pets?
Outlive presents copious experimental data showing that long-term dietary restriction extends lifespan in lab animals. Numerous clinical studies have found the same in dogs, cats, and other companion animals. In a groundbreaking lifetime study that lasted nearly 15 years, researchers at Purina followed 48 Labrador Retriever puppies from 8 weeks of age until they died. One group was randomized to eat 25% fewer calories of a balanced diet while the control group was fed normally. The results were astounding:
“The study revealed that the median life span of the lean-fed dogs was extended by 15 percent or nearly two years. Median life span (the age at which 50 percent of dogs in the group died) was 11.2 years for the control group versus 13 years for the lean-fed dogs.
By age 10, only three lean-fed dogs had died, compared to seven control dogs. At the end of the twelfth year, 11 lean-fed dogs were alive with only one control dog surviving. Twenty-five percent of the lean-fed group survived to 13.5 years, while none of the dogs from the control group lived to 13.5 years.”
In addition to living longer, these dogs had lower lipid and glucose levels, and developed chronic diseases like osteoarthritis, cancer, and hypothyroidism much later in life. These findings have been replicated in dogs and cats in numerous studies.
Wow!
If there was a drug shown in clinical trials to extend life by 15% and improve all of these health parameters without adverse effects it would be a multi-billion dollar blockbuster. Fortunately, it is not a drug and it does not cost any money; managing your pet’s weight is one of the single best ways to maximize the amount of time you can spend with them, yet many of us overlook it.
Final thoughts
Overall, I thoroughly enjoyed reading Outlive by Peter Attia. It’s not your typical self-help book touting the latest fad diet or miracle supplement. Instead, it serves as a guide to understanding aging and how we can slow it, though there are no easy solutions—it requires time and effort. This book is perfect for anyone curious about biology and medicine who wants to improve their health.
While some conclusions are obvious—like losing weight is good for your health, duh—Attia’s detailed descriptions of the mechanisms behind the “Four Horsemen” were enlightening. For someone like me, understanding the “why” behind recommendations makes it easier to stick with them. The book offers actionable insights, not just generic advice like “eat better” or “sleep more.” Since reading Outlive, I’ve increased my strength training and protein intake, started taking an EPA/DHA-rich fish oil supplement for my mildly high LDL-cholesterol, and I’m working on getting at least an hour more sleep each night.
If you would like to dip a toe into the water of Dr. Attia’s work, his podcast The Drive is entertaining and informative. Here's a great free episode to start with:
Attia an incredible communicator. Great review! I wasn’t going to read but will put it on my list.
Great inputs, Eric! Thanks. Attia's book has been on my to-read list for a while.