PDF Summary:Outlive, by Peter Attia

How do you want to spend the last decade of your life? Do you want to be weak, bedridden, and mentally foggy? Or busy doing whatever brings you joy, flexing the body and mind of someone decades younger? According to physician Peter Attia, you can extend the active and fulfilling part of your life by building the right healthy habits—and the earlier you start building these habits, the better chance you have of circumventing mental and physical decline.

In this guide, you’ll learn Attia’s recommendations for how best to eat, exercise, and otherwise take care of your body and mind. You’ll also understand how one chronic condition, metabolic dysfunction, can cause four of the most deadly diseases known to man. In our commentary, we’ll supplement Attia’s explanations of human biology and modern medicine with information from recent research. We’ll also use additional health and fitness tips to paint a broader picture of the current consensus in the complex field of wellness.

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(Shortform note: Attia’s recommendation of three hours a week is slightly higher than the 150 minutes (2.5 hours) recommended by the US Department of Health and Human Services. This may be because Zone 2 exercise is slightly less intense than what most experts prescribe—therefore, you’d need to spend longer doing it to reap the same benefits. If this demand—or the lesser demand of two 30-minute sessions a week—feels so daunting that it’s difficult to motivate yourself to do it, experts recommend spreading this exercise time throughout the day so each session feels more manageable. Even short three-minute exercises can add up to substantial health benefits.)

Stretch Your Physical Limits Through VO₂ Max Training

Second, Attia recommends increasing your VO₂ max: the volume of oxygen that your body can effectively transport and utilize to create energy while you’re pushing yourself to your physical limits. This number, more than any other, precisely reflects your overall physical fitness. The higher your VO₂ max, the more physical activities you’ll be able to perform and enjoy.

Why do you need a high VO₂ max to be physically fit? Attia explains that your cells need oxygen to convert glucose and fats into energy. Exercise increases the demand for oxygen throughout your body, and the more intensely you exercise, the more likely it is that your oxygen demand will exceed your VO₂ max. At this point, your cells lose oxygen and must resort to less efficient means of energy generation. You’ll hit your physical limit and won’t be able to complete whatever physical activity you’re trying to do.

(Shortform note: Since your cells need oxygen during exercise, you may assume that you should inhale as much oxygen as possible to raise your VO₂ max. However, in The Oxygen Advantage, Patrick McKeown argues the opposite: Breathing less is the key to increasing VO₂ max. He asserts that your blood needs carbon dioxide to pass oxygen on to the cells that need it. Often, people breathe too heavily while exercising and exhale all their CO₂. They then lose the ability to utilize oxygen and become exhausted. Instead, if you habitually breathe less, you can train your body to tolerate more CO₂, increasing your VO2 max—thereby helping you accomplish more physical activities as you age.)

VO₂ max declines sharply as you age, so to do all the physical tasks you want to in your elderly years, compensate for this decline by training your VO₂ max as much as possible. Attia adds that aside from enabling an active lifestyle, a high VO₂ max will reduce your risk of disease—research shows that VO₂ max is strongly correlated with a longer lifespan.

(Shortform note: Attia doesn’t specify why a higher VO₂ max in old age would reduce your risk of disease. One simple possibility is that more oxygen to your organs results in better overall health. A low VO₂ max might slightly reduce the oxygen supply to various organs throughout your body—not enough to cause any easily detectable symptoms, but enough to increase your vulnerability to chronic disease.)

To improve your VO₂ max, Attia recommends a high-intensity interval exercise rhythm: Warm up, then perform four-minute spurts of aerobic exercise at the fastest pace you can steadily maintain for those four minutes. Take four minutes of recovery by exercising at a slow, easy pace. Repeat this sprint-rest cycle four to six times, then cool down. Doing this once a week is enough to gradually raise your VO₂ max.

(Shortform note: The rhythm Attia describes here is a form of fartlek. Fartlek is Swedish for “speed play,” and it refers to any exercise in which you alternate between timed periods of strenuous activity and slower recovery. Fartlek is different from typical interval exercises, which require you to cover a certain distance with every rep—for instance, running 12 200-meter sprints with recovery in between. If you’re struggling with Attia’s rhythm, you can work your way up to it with a fartlek that includes more recovery time—two-minute spurts of intense activity followed by four minutes of recovery. As long as you’re pushing yourself to your physical limit, you’re raising your VO₂ max.)

Build Muscle Through Strength Training

Finally, Attia recommends building as much muscle as possible. Research shows that the bigger and stronger your muscles are, the longer you’ll live and the healthier you’ll be.

One reason for this is that the more muscle mass you have, the easier it is to be metabolically healthy. Attia states that muscle tissue is better at metabolizing glucose than other parts of your body, so the more muscle you have, the easier it is to keep your blood sugar low and stable. Additionally, building muscle increases your capacity to store glucose as glycogen for short-term energy consumption, rather than storing it as potentially harmful fat.

(Shortform note: Because your muscle mass significantly determines how efficiently you can metabolize and store glucose, gaining muscle can result in major metabolic improvements even if you're still carrying an unhealthy amount of fat. One study of overweight and obese adults found that the third of participants with the most muscle boasted 45% greater insulin sensitivity than the third of participants with the least muscle. This meant that the cells of more muscular participants could more effectively absorb glucose from their blood, warding off chronic disease.)

Unfortunately, around the time someone turns 65, they begin losing muscle at an alarming rate. Unless you build up above-average muscle mass before this time, your muscle mass will drop low enough during your elderly years to leave you significantly more vulnerable to chronic disease and injury. Attia recommends regular strength training (specifically, weightlifting) to prevent this as much as possible.

(Shortform note: Although extreme muscle degeneration typically doesn’t happen until you’re 65, experts note that without conscious intervention, you’ll start losing significant muscle by age 30: 3 to 5% of your muscle mass every decade. Thus, starting your strength training early can yield significant benefits long before “old age.”)

However, Attia emphasizes that if you perform intense strength training exercises poorly, they can do more harm than good—specifically, if they cause you to badly injure yourself. Train yourself to use the proper form when practicing strength exercises, and use lighter weights until you’ve built up the bodily awareness you need to avoid injury when lifting heavier weights.

(Shortform note: In The 4-Hour Body, Tim Ferriss contends that most injuries during strength training are caused by imbalances—when one side of your body (or one half of the same muscle group) is much stronger and more developed than the other. If any of your muscles feel imbalanced in this way, make sure to correct it before attempting any full-strength exercises. Additionally, using weights that are too light can sometimes cause you to develop improper form, so ensure that you’re using weights heavy enough to realistically replicate the strain that the full-strength exercise will put on your body.)

What Should I Eat?

In addition to exercising correctly, eating a healthy diet is key to maintaining your physical and mental capabilities in old age. Attia emphasizes that what you should eat depends on your unique body—there’s no diet that’s universally the “healthiest” for everyone. Everyone’s body metabolizes food differently, so the exact same diet might help one person and harm another.

(Shortform note: Individuals’ widely varying metabolic reactions to the same food have cast doubt on countless widely accepted conclusions from nutritional research. Traditionally, studies have compared an experimental group, who all change their diet in the same way, to a control group whose diet stays the same. However, this setup doesn’t account for differences between the two groups’ metabolisms—even if the groups are randomly selected, they won’t always be identical samples of the population. Instead, some researchers are now running a different kind of study: one in which individual participants stick with one diet for several months, then swap to another. This allows researchers to study the effects of different diets on the same metabolism.)

Although there’s no universally optimal diet, Attia offers broad dietary advice that would improve the health of most people. In modern times, many follow what’s called the Standard American Diet, which is heavy in processed, sugary foods. Consequently, they consume too many calories (which contributes to metabolic dysfunction, as we’ve discussed), yet they still don’t get enough of some key nutrients (especially protein, as we’ll see soon).

(Shortform note: Although experts call it the Standard American Diet (SAD), this unhealthy eating pattern isn’t unique to America. One study found that many European countries, including Sweden, France, and Germany, consume the SAD’s processed foods at a comparable rate to the United States. Additionally, many countries in the Eastern Hemisphere have shifted their diet toward the SAD in recent years. This includes India, where instances of diabetes tripled from 1995 to 2014, and China, where rates of obesity quadrupled between 1995 and 2019.)

As we’ll explore in this section, Attia asserts that most people should do the following:

• Eat more protein
• Eat fewer carbohydrates
• Complete their diet with fats
• Only fast if they have metabolic dysfunction

Finally, as a side note, Attia states that as long as your metabolism is relatively healthy, practicing the ideal exercise routine is more important than consuming the ideal diet. Although fixing your diet is essential if you’re suffering from intense insulin resistance, perfecting your diet yields far fewer health benefits than perfecting your exercise routine.

(Shortform note: This idea contradicts some common wisdom in the field of health and fitness. Some health experts cite the “80/20 Rule”: If you want to lose weight, you need to retain fewer calories. Avoid 80% of those calories by eating less, and burn the other 20% through exercise. This advice disregards the fact that exercise helps you lose weight primarily by improving your metabolism, not by burning calories.)

Most People Should Eat More Protein

According to Attia, most people consume far less protein than their body needs for optimal health. The body uses protein for countless essential tasks, converting it into important enzymes, hormones, and muscle mass. (As we’ve discussed, building muscle is necessary to increase health and longevity.)

(Shortform note: Because the enzymes and hormones your body creates with protein are so vital to survival, severe protein deficiency, or kwashiorkor, disrupts basic biological processes, causing much more serious problems than diminished muscle mass. Kwashiorkor can result in a weakened immune system, permanently stunted physical and mental development, coma, and death.)

Although US government agencies recommend consuming 0.8 grams of protein per kilogram of body weight a day, Attia asserts that most people need at least double that—1.6 grams per kilogram. If you’re active and trying to gain muscle (as almost everyone should be), Attia recommends 2.2 grams per kilogram (or 1 gram per pound of body weight) of protein.

Whereas excess calories from glucose are sometimes stored in unhealthy ways, your kidneys will filter out any excess protein and you’ll excrete it through urine. Therefore, it’s very difficult to eat too much protein—3.7 grams per kilogram of body weight will strain your kidneys, but the vast majority of people never come close to consuming that much.

(Shortform note: It’s rare for people to contract kidney disease by eating too much protein. Rather, two out of every three cases of chronic kidney disease are caused by diabetes and high blood pressure (both signs of metabolic dysfunction). Attia would likely argue that increasing your protein intake will almost always reduce your risk of kidney disease, as building muscle improves your metabolic function.)

The Risks of Eating Too Much Meat

After hearing Attia’s argument that most people fail to eat enough protein, you may decide to add significantly more meat to your diet. However, excess meat consumption can cause a number of health issues: Both red and white meat are high in saturated fats, which (as we’ll discuss in more detail later) increases some individuals’ risk of heart disease. Additionally, processed meats such as ham, bacon, and sausage are particularly high in sodium, which research indicates may increase your risk of high blood pressure, bowel cancer, and stomach cancer.

This means that getting the amount of protein you need solely from meat may trigger adverse health effects. For example, if you weigh 170 pounds and want to gain muscle, Attia recommends consuming 170 grams of protein per day. To reach this target by eating nothing but ground beef with taco seasoning for one day, you’d consume over 1.5 pounds of beef containing an unhealthy 41 grams of saturated fat (209% of the FDA recommendation) and 5,800 milligrams of sodium (256% of the FDA recommendation).

Instead of increasing your protein intake solely through meat, it would likely be healthier to balance your diet with other protein-rich foods like nuts, beans, and quinoa.

Most People Should Eat Fewer Carbs

Most people consume too many carbohydrates, asserts Attia. Although the body uses carbohydrates as its main source of energy, when you consume too many, they raise blood glucose and trigger the overproduction of insulin. This is because your body converts carbohydrates into glucose more readily than any other food group.

That said, Attia notes that carbohydrates in moderation are healthy—and they’re healthier for some people than others. For instance, although it would be atypical, you may find that cutting carbohydrates out of your diet doesn’t help you burn fat or reduce your blood sugar.

(Shortform note: Carbohydrates are particularly healthy for endurance athletes, who need a high-carb diet to maintain their physical performance. Unlike most people, endurance athletes nearly deplete the glycogen stores in their liver and muscles, the human body’s primary source of short-term energy, on a regular basis. To them, carbohydrates are valuable for the same reason they’re unhealthy for others: The body converts them directly into vast amounts of glucose, which can replenish these glycogen stores. Experts assert that most athletes don’t eat enough carbohydrates—a 175-pound endurance athlete needs upwards of 3,800 calories every day just from carbs to replenish their glycogen.)

The only way to know for sure how your unique metabolism processes carbohydrates is to experiment with your diet until you’ve found one that helps you reach your health goals.

To help you do this, Attia recommends using a continuous glucose monitor (CGM), an implantable device that allows you to stay aware of your blood sugar levels at all times. Spikes in blood glucose after you’ve eaten something high in carbohydrates indicate times when your body will produce extra insulin in response. By observing what quantities of specific foods cause your glucose (and insulin) to spike, you can learn to avoid or reduce your intake of those foods in the future. Over time, this helps you keep your blood glucose low and avoid insulin resistance.

(Shortform note: CGMs are generally slightly less accurate than traditional blood glucose meters, which read blood drawn from your finger. This is because they don’t directly measure blood sugar. Rather, they measure the amount of glucose in your body’s interstitial fluid—the plasma-like liquid that fills your body outside of your blood vessels—and use that to estimate blood glucose. This inaccuracy makes CGMs more suitable for getting a vague sense of what foods are good for your metabolism rather than determining your exact glucose levels for medical purposes (like helping your doctor know how much supplemental insulin to prescribe).)

Complete Your Diet With Fats

When you reduce your consumption of carbohydrates and eat the necessary amount of protein, the rest of your diet will primarily be made of fats. This is perfectly healthy, according to Attia.

Generally speaking, foods high in monounsaturated fats (like olive oil) are healthier than foods high in polyunsaturated fats (like nuts and fish) or foods high in saturated fats (like beef and butter). Attia estimates based on anecdotal evidence that one-third to one-half of people react badly to a diet heavy in saturated fats—it causes them to produce significantly more LDLs and other unhealthy forms of cholesterol, increasing their likelihood of heart disease. That said, for those whose bodies can process it well, saturated fat is perfectly healthy to eat.

(Shortform note: According to Michael Pollan in In Defense of Food, the main reason people believe that dietary fat is so unhealthy is that lobbyists pressured government agencies into popularizing this idea. In 1977, a US Senate committee reported that eating too much red meat and dairy caused heart disease; however, pushback from the meat and dairy industries caused them to retract their findings and instead blame the saturated fats and cholesterol contained in those foods. This allowed corporations to market “healthier” low-fat processed foods like margarine, which ended up also causing heart disease.)

The Drawbacks of “Healthy” Fats and the Benefits of “Unhealthy” Fats

Because saturated fats are the only fats with a chance of increasing your risk of heart disease, you may assume that a diet of low saturated fats and high poly- and monounsaturated fats would be ideal for anyone. (One such diet would be the Mediterranean diet, heavy in fish and fatty oils and light on red meat and dairy products like butter.) However, this may not be the case—especially for the one-third to one-half of the population that can process saturated fats just fine.

Monounsaturated and polyunsaturated fats have some potential drawbacks. Olive oil, a great source of monounsaturated fat, is surprisingly calorically dense. Just one tablespoon of olive oil contains 120 calories. Similarly, nuts like pine nuts and walnuts (which contain polyunsaturated fats) are lightweight but dense with calories. If you’re not careful, the caloric density of these foods may sneak up on you, causing you to gain weight.

Furthermore, increasing your intake of certain types of saturated fat may yield unexpected health benefits. For instance, the saturated fats caproic, caprylic, and capric acid (known collectively as Medium Chain Triglycerides, or MCTs) have been shown to help your body burn calories, decrease insulin resistance, and prevent seizures. These benefits are potent enough that these saturated fats are sold as dietary supplements.

Fasting Is Sometimes Good for You (But Usually Bad)

Attia notes that in recent years, fasting—restricting your calorie intake for fixed periods of time—has become an incredibly popular health trend. But is it good or bad for you?

Fasting is exactly what some people need. If you find fasting easier than trying to follow strict dietary rules, it can help you reduce your calorie intake to a healthy level. Additionally, within three days of fasting, you’ll trigger starvation ketosis—your body burns fat stores to keep you from feeling hungry, and your cells recycle stray waste materials into functional parts in a process called autophagy.

However, Attia argues that in many cases, fasting can be detrimental to your health. It’s nearly impossible to eat enough protein to support your body during a fast, so you’re likely to lose muscle (which is very unhealthy, as we’ve discussed). For most people, this is too great of a sacrifice to make: Only fast if you have metabolic dysfunction and desperately need to burn fat to avoid chronic disease.

Counterargument: Fasting Is Healthy for Everyone

In The Obesity Code, Jason Fung takes a much stronger pro-fasting stance than Attia, arguing that fasting is essential to reverse insulin resistance. Fung asserts that if you’re metabolically unhealthy, your body believes it needs more food than is healthy, sending signals that make it incredibly difficult to stick to a healthy diet:

• Your metabolism slows, burning less energy and storing more glucose as fat.

• You produce less leptin, the hormone that makes you feel full and satisfied after eating.

• You produce more ghrelin, a hormone that makes you feel hungrier.

This creates a vicious cycle in which you crave and eat more food, raising your insulin and further disrupting your hormones.

According to Fung, fasting is the key to escaping this cycle, as triggering ketosis significantly lowers your insulin levels. This is arguably the reason some people find fasting much easier than sticking to a strict diet (which may explain why fasting is popular). It’s not just that its rules are easier to follow, as Attia claims—it also resets your hunger hormones to reduce feelings of craving. Fung recommends regularly fasting for 24 to 36 hours at a time, and he notes that your insulin levels will fall after just 24 hours. He also argues that you can trigger ketosis in two to three days, rather than the three days Attia contends.

Unlike Attia, Fung believes that fasting is beneficial for everyone. In an episode of Attia’s podcast The Drive, Fung explains why he doesn’t share Attia’s concerns about muscle loss from reduced protein intake. He contends that, when fasting, the body gets much of the protein it needs through autophagy, recycling excess protein such as loose skin rather than breaking down muscle.

How Else Can I Stay Healthy?

Alongside exercising and amending your diet, Attia also highlights a couple of other habits that are important to staying healthy: getting enough sleep and taking care of your emotional health.

Get Plenty of High-Quality Sleep

To improve your health and longevity, get more sleep. Attia notes that sufficient sleep gives your brain time to organize its memories, while insufficient sleep results in short-term damage to memory and mental acuity.

(Shortform note: You can claim these short-term neurological benefits of sleep with a midday nap. Naps that last 30 minutes or more trigger the process of memory consolidation Attia mentions. Further, studies have found that napping can increase your alertness and cognitive performance for up to three hours after waking.)

Additionally, during sleep, your brain cleans away harmful proteins that accumulate between your neurons during the day. If you don’t give your brain time to do this, these proteins will accumulate and cause long-term damage—including neurodegenerative diseases like Alzheimer’s.

(Shortform note: A 2019 study sheds more light into what’s happening inside your brain during this protein-cleaning process that wards off neurodegeneration. The slow electric brain waves that occur during deep sleep reduce blood flow to the brain. This blood movement draws more cerebrospinal fluid up into the skull, where it can wash away harmful proteins. Because this interaction is controlled by brain waves, the cerebrospinal fluid can wash proteins out of the brain repeatedly in a wave-like cycle.)

Furthermore, multiple studies suggest that poor sleep disrupts your metabolism, making metabolic dysfunction and chronic disease much more likely. Although researchers aren’t totally sure why this is, Attia theorizes that it’s because insufficient sleep puts your body into perpetual fight-or-flight stress. The stress hormone cortisol raises blood pressure and triggers the liver to release glucose into the blood. This can lead to insulin resistance and an increased risk of chronic disease.

(Shortform note: It’s likely that the stress response is only part of the reason why insufficient sleep causes metabolic dysfunction. In Why We Sleep, Matthew Walker affirms that sleep deprivation floods your system with the hormone cortisol, and he goes on to describe the other hormonal problems caused by lack of sleep: Your body increases production of the hormone ghrelin and reduces leptin, both of which cause you to feel hungrier. This, in addition to the reduced emotional control you have while sleep-deprived, often leads to overeating—which, as we’ve discussed, is one of the primary causes of metabolic dysfunction.)

Take Care of Your Emotional Health

Finally, Attia emphasizes the importance of taking care of your emotional health. Attia recounts his lifelong journey to overcome feelings of rage toward others and himself, both of which had roots in his childhood trauma.

Often, children who go through traumatic incidents (big and small) adopt emotional coping strategies that hurt them in later adulthood—like how Attia learned to feel angry at himself and others to avoid dealing with the shame from his childhood trauma. Attia recommends using psychotherapy as a tool to uncover how you’ve adapted to past traumas and to develop a plan to repair your unique emotional dysfunction. Doing so, he argues, is the surest way to achieve an emotionally fulfilling life.

Using Internal Family Systems to Resolve Trauma

Attia worked through his childhood trauma in a relatively emotionally detached way—using reason to dissect his past experiences and identify his coping strategies. In contrast, you may prefer the more emotion-driven method of imagining your coping strategies, both healthy and unhealthy, as “subpersonalities” within yourself—a therapy model called Internal Family Systems (IFS). In IFS, each “part” or version of yourself has its own perspective and goals, and they’re all trying to help you in their own ways.

One way you could heal your emotional scars with IFS is by asking yourself what each part of yourself is thinking and feeling about the trauma, listening to what that part of you has to say, and formulating a new plan that all parts of you can agree on. For instance, Attia could have asked the rage-filled part of himself why it was so angry at himself and other people, uncovering some of the emotional logic behind his own behavior. Then, he could have used this information to come up with healthier coping strategies that satisfied the angry part of himself. If this process appeals to you, consider looking for an IFS-certified therapist to work with.