PDF Summary:Good Energy, by Casey Means

Do you struggle with fatigue, brain fog, or unexplained health issues? In Good Energy, Dr. Casey Means explains that these symptoms often stem from metabolic dysfunction—when your cells can't efficiently convert food into energy. She argues that this "Bad Energy" is the root cause of many chronic diseases, from heart disease and diabetes to depression and infertility.

Means traces metabolic dysfunction to the mismatch between our modern lifestyle and our evolutionary biology. She explains how processed foods, sedentary habits, and environmental stressors damage our cells' energy-producing mitochondria. The guide then outlines practical interventions to restore metabolic health, including dietary changes, movement strategies, sleep optimization, and temperature exposure techniques. You'll also learn how to use tracking tools like continuous glucose monitors to understand your body's responses and make informed decisions about your health.

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(Shortform note: A 2016 meta-analysis by Ulf Ekelund et al. found that sitting for more than eight hours a day was associated with a higher risk of death, but only among people who did less than five minutes of moderate-to-vigorous exercise per day. For those who exercised for about an hour a day, sitting time didn't seem to affect their risk of death. This suggests that the negative effects of sitting can be offset by regular exercise. The study included over a million people from 16 different studies, making it one of the largest analyses on this topic. The authors concluded that "high levels of moderate intensity physical activity (about 60–75 minutes per day) seem to eliminate the increased risk of death associated with high sitting time." This challenges the idea that sitting is harmful regardless of activity level.)

The real villain is sitting, even if you exercise. For exercise to have a substantial effect on metabolism, it must differ significantly from the modern fitness industry. Instead, it'll involve weaving consistent activity into our daily routines again. Our musculoskeletal system operates harmoniously, enabling us to perform actions like running, jumping, climbing, and raising objects with extraordinary accuracy and effectiveness. We're wasting these incredible abilities. Moving frequently matters because the physiology of a body with muscles contracting often—even at low intensities and for short periods—differs entirely from a body whose muscles are exercised in a single one- to two-hour block each day, regardless of that block's intensity.

(Shortform note: The idea that sitting is the real villain, even if you exercise, is supported by research showing that prolonged sitting can have detrimental effects on your health, regardless of your exercise routine. When you sit for extended periods, your large postural muscles are almost completely inactive, which can lead to a significant decrease in the activity of enzymes like lipoprotein lipase that help clear fats from your bloodstream. This means that even if you hit the gym for an hour, the other 23 hours of inactivity can still negatively impact your metabolism. On the other hand, frequent muscle contractions throughout the day, even at low intensities, can keep these molecular systems switched on, creating a very different physiological state.)

The act of contracting muscles is incredibly beneficial. Exercise encourages the production of more mitochondria, and healthier ones, to produce Good Energy, enhancing antioxidant defenses and reducing inflammation over time. Increasing movement frequency leads to ongoing blood glucose clearance throughout the day. Getting up and walking for five minutes or doing thirty air squats signals your body to relocate glucose channels to the membrane, maintaining the removal of glucose to create ATP. This contrasts with a person who sits for hours and then works out for sixty minutes at night. Throughout the day, the muscles don't receive a cue to absorb and utilize excess glucose, so it continues to flow in the bloodstream and needs insulin to move into the cells. To be effective, you should move frequently throughout the day, but it doesn't have to be intense.

(Shortform note: When Means says that movement causes muscles to “relocate glucose channels to the membrane,” she’s referring to a process that exercise physiology researchers have studied in detail. In a research article, they explain that when you contract your muscles, it triggers a process that moves glucose channels (called GLUT4) from inside the cell to the cell’s surface. This creates extra gateways for glucose to enter the cell, independent of insulin. This process is different from how insulin normally works to move glucose into cells. The researchers note that this insulin-independent pathway is especially important for people with insulin resistance, as it provides an alternative way for their muscles to absorb glucose.)

Eleven people participated in research testing four different activity schedules: no exercise; jogging for twenty minutes before meals; jogging for twenty minutes after meals; and brief, three-minute jogging intervals every thirty minutes. Each of the three exercise regimens totaled an hour of daily jogging. Brief, three-minute runs every thirty minutes led to a notable decrease in glucose spikes after meals, unlike the longer runs before and after meals. Running isn't necessary to get this benefit—walking also has an impact.

(Shortform note: The study Casey Means cites here was conducted on healthy adults. For people with diabetes who use insulin, unplanned exercise can cause dangerous drops in blood sugar. The authors of a 2023 review on exercise and diabetes note that unplanned activity is a common trigger for hypoglycemia in insulin users. They recommend adjusting insulin doses and/or eating extra carbohydrates before exercise to prevent low blood sugar. This means that the routine in the study—three-minute jogs every thirty minutes—can’t be copied directly by people with diabetes who use insulin.)

Research on seventy adults of healthy, normal weight examined three comparable situations: nine hours of sitting, a single thirty-minute walk per day followed by sitting, and taking regular breaks to walk for 100 seconds each half hour. Both groups accumulated a half-hour of walking each day, but the research revealed that those who took short walks at thirty-minute intervals experienced the smallest glucose spikes and insulin responses after meals.

(Shortform note: This study was not the first to examine the effects of breaking up long periods of sitting with short walks. In 2012, researchers found that overweight or obese adults who took short walks during long periods of sitting had lower glucose and insulin levels after meals. This research article was one of the first to show that breaking up sitting time with short walks can help control blood sugar and insulin levels, which is important for preventing diabetes and other health problems.)

Means likens movement to consuming water. If your body requires approximately 90 ounces of water daily to function optimally, it doesn't make sense to consume all of it within a half-hour, then not drink for the remainder of the day. It’s clearly more beneficial to sip the 90 ounces over the course of a day. The same goes for movement. Although frequent "stand up" notifications on devices such as smartwatches might be bothersome, these suggestions are supported by strong scientific evidence and could be the most valuable nudges wearables provide.

(Shortform note: Randomized trials of smartphone and wearable activity prompts show that these cues reliably break up long sitting bouts, supporting the value of frequent "stand up" notifications on devices such as smartwatches. These interventions, which deliver just-in-time prompts to stand or move, have been shown to significantly reduce prolonged sedentary periods in both laboratory and real-world settings. The evidence suggests that such digital nudges can be an effective tool for promoting healthier movement patterns throughout the day.)

The idea of increasing movement during the day, distinct from exercising, is known as NEAT. NEAT describes all unplanned movement that's not intentional exercise. Before jobs became urbanized and work shifted to desks, NEAT was simply a way of life. NEAT means everyday activities involving physical movement, such as cleaning, buying groceries, gardening, doing house chores, walking from your vehicle to a shop, going upstairs, standing while working, and playing with children—even fidgeting counts. Increasing NEAT could be a key method for managing body weight. A walking desk is one way to incorporate additional NEAT into your daily routine.

The Impact of NEAT on Weight Management

To demonstrate the importance of NEAT, researchers conducted a study in which they overfed participants by 1,000 calories per day for eight weeks. The participants were instructed not to change their exercise routines. The results showed that some participants gained significantly more weight than others, despite consuming the same excess calories. The key difference was in their NEAT levels. Those who naturally increased their daily movements—such as standing, walking, and fidgeting—burned up to 700 more calories per day than those who remained relatively motionless. This study highlights how NEAT can play a crucial role in managing body weight, even when calorie intake is high.

Nutrient & Movement Practices

Means suggests that consuming omega-3-rich foods can help reduce inflammation. Omega-3s are polyunsaturated fatty acids that play a crucial role in cell structure and metabolic and inflammatory pathways. They help reduce inflammation by countering omega-6s, which are fats that cause inflammation when consumed in excess. The typical diet in the West can have a 20-to-1 proportion of omega-6 to omega-3 fatty acids, but it should be nearer to 1:1.

(Shortform note: The Office of Dietary Supplements (ODS) at the National Institutes of Health disagrees with Means’s assertion that omega-6s are generally inflammatory and that we should aim for a 1:1 ratio of omega-6s to omega-3s. The ODS states that the idea of an “ideal” ratio is based on the assumption that omega-6s are pro-inflammatory, but clinical trials have not shown that higher linoleic acid intake increases inflammatory markers or cardiovascular risk. As a result, expert groups do not recommend reducing omega-6 intake solely to alter the omega-6:omega-3 ratio.)

This is because people consume a lot of refined oils from seeds and vegetables, which are rich in omega-6s, and eat little whole foods high in omega-3s. The balance between omega-6s and omega-3s in what you eat dictates the proportion of these fats in your cell membranes, such as in immune cells. Omega-6 fats can be utilized by immune cells to create signaling molecules that prolong an inflammatory response. They can also utilize omega-3s to create signaling molecules that reduce genetic inflammation pathways and resolve the inflammatory process. Omega-3s can immediately lower the primary inflammatory pathway's activity following an inflammatory episode.

(Shortform note: Some nutrition researchers argue that the amount of omega-6s in seed and vegetable oils isn’t inherently inflammation-prolonging. For example, a study found that linoleic acid, a major omega-6 fat, doesn’t increase markers of inflammation in healthy people. The researchers concluded that there’s no need to restrict linoleic acid intake to prevent inflammation. However, this research article doesn’t address the impact of omega-6s on immune cell signaling, which is the focus of Means’s argument.)

To get more omega-3s in your diet, Means recommends eating chia and basil seeds, flaxseeds, walnuts, hemp seeds, sardines, mackerel, herring, anchovies, salmon, trout, fish roe or caviar, oysters, and pasture-raised, 100% grass-fed game meats such as venison, bison, beef, lamb, and eggs.

(Shortform note: While the fish and shellfish on this list are generally considered safe to eat, some of them can contain methylmercury, a neurotoxin that can cause long-term health problems. If you’re not used to eating these foods, be careful not to overdo it. Methylmercury is especially dangerous for fetuses and young children, so if you’re pregnant or have young children, be sure to follow the FDA’s guidelines for eating fish.)

Optimizing & Monitoring for Enhanced Energy

Means suggests using food journaling to monitor your intake and identify areas for improvement. This involves keeping a record of everything you eat and drink, including the time, quantities, and the brands of packaged foods. Food journaling helps you understand your relationship to what you eat and identify areas for improvement. It can help you lose weight and stick to nutritious eating habits. It also helps confirm that you're receiving the nutrients necessary for good energy. Research indicates that individuals who keep food diaries shed double the weight of those who don’t.

To start, log each thing you eat in a notebook, digital entry, or food logging app. Examine your food journal each week to assess your eating habits and identify any barriers to healthy eating.

The Potential Downsides of Food Journaling

While food journaling can be a helpful tool for many, it may not be suitable for everyone. For some individuals, keeping a detailed food journal can increase anxiety and obsessive thoughts about food, potentially leading to disordered eating patterns. Research shows that calorie counting and fitness tracking technology can increase the risk of eating disorders in some people. The constant monitoring and quantification of food intake can create a sense of guilt or failure when goals aren’t met, leading to unhealthy restriction or bingeing behaviors. Additionally, the focus on numbers rather than overall well-being can cause people to ignore their body’s natural hunger and fullness cues. If you have a history of disordered eating or find that food journaling causes you stress, it may be best to explore alternative methods for improving your eating habits.

Means also recommends using wearable technology to monitor your physical movement, pulse, and rest. This information can help ensure you’re achieving your objectives.

(Shortform note: To use wearable technology to monitor your physical movement, pulse, and rest, consider the following: Each evening, review your wearable technology’s daily summary to see how your physical movement, pulse, and rest lined up with one objective you care about. Then, jot a brief note about one small change you’ll test tomorrow based on that pattern.)

Additionally, ongoing glucose monitoring can provide valuable insights into your well-being. A continuous glucose monitor is a tiny plastic disk you wear on your arm that automatically checks your blood sugar every ten minutes around the clock, sending that data to your smartphone.

(Shortform note: While continuous glucose monitoring can provide valuable insights into your health, it may also have some downsides. Some researchers argue that turning your body’s sugar dynamics into a constantly updated metric can erode your intuitive self-trust and create a sense of being perpetually under surveillance.)

A CGM can notify you of initial dysfunction, guide you on eating and living to foster good energy, and encourage accountability. It shows precisely how your body responds immediately to all of your actions, such as eating, exercising, walking, having a bad night’s sleep, or dealing with stress. These elements can affect your glucose almost instantly. A CGM can help you improve glycemic variability, reduce cravings and anxiety, learn your reaction to individual foods and meals, learn ways to keep glucose stable, catch metabolic dysfunction earlier, and motivate behavior change. It can also help you understand the impact of exercise and sleep on your glucose levels.

(Shortform note: Some people who don’t have diabetes and use a CGM become fixated on the numbers, which can lead to unnecessary worry. For example, some people may become overly concerned about minor fluctuations in their glucose levels, even though these are normal and not harmful. Others might start to restrict their diet excessively to keep their glucose levels within a narrow range, which can lead to unhealthy eating habits.)

Let’s take a closer look at how you can optimize and monitor your well-being for enhanced energy.

Active Optimization

Means explains that exposing oneself to hot and cold conditions can benefit metabolism. Cold exposure can activate brown fat, a special type of fat that burns calories to generate heat. This type of fat is brown due to its mitochondria content and its expression of a protein named uncoupling protein one. The brown fat–specific UCP1 protein enables the fat to generate heat rather than ATP. Mitochondria are less stimulated in our current lives, which are thermally neutral. These structures generate heat, but if we don’t activate them to perform the work of creating heat and ATP, they won’t do as much.

(Shortform note: The idea of leaving thermally neutral comfort to stimulate brown fat and mitochondria for metabolic benefits emerged from research on cancer patients. In the early 2000s, researchers noticed that PET–CT scans of cancer patients revealed unexpected areas of high metabolic activity in the neck and upper chest regions. These areas were initially thought to be tumors, but further investigation revealed that they were actually deposits of brown adipose tissue (BAT). This discovery challenged the long-held belief that BAT was only present in infants and small mammals. Scientists began to explore the potential of BAT in adult humans, leading to a study published in 2009 that confirmed the presence of metabolically active BAT in adults.)

Our mitochondria have become so neglected and mistreated that our species seems to be getting colder. Over the past two centuries, body temperature appears to have declined by up to 1.06°F, perhaps due to a widespread decrease in metabolic rate. Recent research highlights that reintroducing significant temperature variations into our routines can benefit metabolism by enhancing vascular function, boosting the capacity of cells to produce their own heat, and improving antioxidant capacity. When we experience cold, our bodies use various methods to maintain internal temperature. Shivering is one method; the muscles quickly contract, which breaks ATP molecules to produce warmth.

(Shortform note: The idea that our body temperature has declined over the past two centuries comes from the work of 19th-century German physician Carl Wunderlich, who measured the body temperature of over 25,000 patients and established the “normal” body temperature as 98.6°F. However, researchers have since found that the average body temperature has decreased by about 1°F since Wunderlich’s time. This decline has been confirmed by a research article that analyzed three large datasets of body temperature measurements from the 19th, 20th, and 21st centuries.)

Another method is non-shivering thermogenesis, where a person creates and uses a unique form of metabolically beneficial fat, known as brown fat, to help maintain warmth. In the colder months, as the body adjusts to maintain warmth, brown fat levels rise. HbA1c levels (a marker of average glucose levels) tend to be lower in the winter, when temperature is colder and brown fat levels are higher, although a causal relationship between HbA1c and brown fat has not been established. Research indicates that brown fat easily absorbs and uses glucose, and that individuals with a greater amount of it often have reduced body mass and glucose concentrations. Research conducted in 2021 showed that people with obesity who had brown fat were almost half as likely to develop type 2 diabetes as those with obesity who lacked brown fat, with the respective rates being around 8% and 20%.

(Shortform note: One justification for the link between higher brown fat levels and lower glucose levels is that brown fat acts as an endocrine organ, releasing signaling molecules that influence how the liver produces glucose and how the pancreas secretes insulin. This means that brown fat could directly affect how the body manages blood sugar, potentially lowering the likelihood of type 2 diabetes. This idea is supported by research articles, scientific papers, and academic papers that discuss how brown fat releases various signaling molecules, known as “batokines,” that can influence the function of other organs. For example, researchers have found that brown fat can release batokines that affect the liver’s production of glucose and the pancreas’s secretion of insulin. This suggests that brown fat could play a role in regulating blood sugar levels and reducing the risk of type 2 diabetes.)

Cold exposure can stimulate brown adipose tissue, helping control blood sugar levels. According to studies, men who are in good health may see their insulin sensitivity rise and brown fat that is twice as active and voluminous if they sleep for a month in a room set to 66°F. Brief cold exposure can boost how the body reacts to insulin and disposes of glucose, particularly for those who have brown fat. Research found that individuals who have brown fat experienced a 15% rise in resting energy expenditure after wearing cooling vests for five to eight hours.

(Shortform note: In a research article, biomedical researchers explain how they used a special imaging technique to see how the body uses glucose in different tissues. They found that when healthy men were exposed to mild cold, a small area of fat near the neck and shoulders started burning fuel at a much higher rate than almost any other tissue in the body. This area of fat, called brown adipose tissue, acts like a focused sink for glucose, helping the body manage blood sugar levels more effectively.)

The entire body's glucose disposal increased by roughly 13% in individuals who had brown fat, but there wasn't a notable change in those who lacked it. Acclimating to the cold can also benefit metabolic health, even for individuals with a low level of brown fat. Ten days of cold acclimation increased insulin sensitivity by 43% in men with type 2 diabetes compared to when they were at regular temperatures. The program also boosted the function of the GLUT4 glucose channel.

(Shortform note: While researchers have observed that cold acclimation increases insulin sensitivity and GLUT4 activity, the exact mechanisms behind these effects are still being studied. One research article suggests that repeated exposure to mild cold temperatures activates the sympathetic nervous system, which in turn triggers molecular changes in skeletal muscle fibers. These adaptations may include increased production and improved mobilization of GLUT4 transporters to the cell surface, allowing muscle cells to respond more effectively to insulin and remove more glucose from the bloodstream.)

Research has shown that greater levels of brown fat are linked to reduced glycemic variability, which aids in keeping whole-body glucose levels stable even without cold exposure. A 2016 study published in Cell Metabolism had subjects consume a drink containing 75 grams of glucose in a 75°F setting. The study observed increased brown fat activity and resting energy use, despite the absence of cold exposure, because the way the brown fat absorbed and used glucose produced heat. The study indicated that low levels of brown fat might clinically signify the beginning of blood glucose regulation issues. To put it plainly, we need a lot more brown fat, and the most effective way to increase it is to subject your body to cold so it adapts. Means says that intentionally exposing yourself to heat can benefit metabolic health.

(Shortform note: While Means suggests that exposing yourself to cold and heat can benefit your metabolic health, it’s important to note that extreme temperatures can also pose health risks. Spending time in very hot or very cold environments can put a strain on your cardiovascular system, potentially leading to heart and circulation problems. When you’re exposed to cold, your blood vessels constrict to conserve heat, which can increase blood pressure and make your heart work harder. This can be particularly dangerous for people with existing heart conditions or high blood pressure. On the other hand, extreme heat causes your blood vessels to dilate, which can lead to dehydration and a drop in blood pressure. This can also put stress on your heart and potentially lead to heat-related illnesses like heat exhaustion or heat stroke.)

Researchers believe that consistently using saunas leads to "a broad adaptation response to stress" that's "potentially similar to the...response" exercise responses.” Exposure to heat can also boost the synthesis of the protein HSP70 (heat shock protein 70). HSP70 participates in numerous cellular activities, such as stress responses and inflammatory processes. Research indicates that HSP70 could help enhance the body's insulin sensitivity and decrease inflammation. Heat exposure also boosts nitric oxide, a compound that aids in relaxing blood vessels and enhancing circulation. Improved circulation may help skeletal muscles take in more glucose, potentially boosting insulin sensitivity. Research has shown that these mechanisms link heat exposure to lowered blood pressure, better heart health indicators, and reduced levels of LDL cholesterol, total cholesterol, and fasting blood sugar.

(Shortform note: While deliberate heat exposure may offer health benefits for many people, it may not be suitable for everyone. For example, people with multiple sclerosis (MS) may experience a temporary worsening of symptoms when their body temperature rises. This phenomenon, known as Uhthoff's phenomenon, occurs because heat can temporarily impair the function of already damaged nerves in the central nervous system. While the effects are usually reversible once the body cools down, the temporary increase in symptoms can be distressing and potentially dangerous. Therefore, people with MS should consult their neurologist before engaging in deliberate heat exposure practices like sauna use.)

A study observing Finnish men showed significant declines in metabolic disorders for those who frequently used saunas: sudden cardiac death (63% less) and all-cause mortality (40% less) decreased, as did dementia (66% less) and Alzheimer's disease (65% less), for those using saunas 4-7 times weekly compared to once weekly. Experiencing both hot and cold temperatures can substantially enhance mood. Studies indicate that immersion in cold water may increase dopamine by two and a half times. Research shows that exposure to cold can stimulate the fight-or-flight system and trigger the discharge of brain chemicals such as norepinephrine, potentially enhancing mood and alertness. Frequent sauna sessions have demonstrated a capacity to decrease cortisol, which is the primary hormone linked to stress. Heat seems to boost antioxidant defenses, which can positively influence oxidative stress that adds to Bad Energy.

(Shortform note: The reason Finnish men were the focus of these studies is that sauna bathing has been a central part of Finnish culture for centuries. In Finland, saunas are a common household feature, and the practice of sauna bathing is deeply ingrained in daily life. This widespread and consistent use of saunas across the population provides researchers with a large, culturally uniform group to study, making it easier to observe and compare the health effects of sauna bathing based on frequency of use.)

To incorporate exposure to cold into your routine, Means recommends finishing your showers with a two-minute blast of cold water or plunging into cold water.

(Shortform note: To decide which method is best for you, choose the one that feels uncomfortably cold but still allows you to breathe calmly. This “controlled discomfort” zone is the safest way to adapt to cold exposure. If you find yourself gasping or shivering uncontrollably, the water is likely too cold for your current tolerance level.)

You can also use Meetup, social media, or Google to look for a local group that does cold plunges or uses saunas. Other options include participating in heated yoga sessions, such as Bikram Yoga or Modo Yoga, where the environment is kept at more than 100°F during the session, or exercising outdoors in hot weather (while ensuring you drink plenty of water, eat sufficiently, and avoid sunburn). Find a local facility that has a steam room or hot tub. Dr. Andrew Huberman reviewed the research and suggested spending 57 minutes in a hot sauna weekly, and having 11 minutes of weekly cold exposure, as reliable thresholds to obtain significant advantages in metabolism, insulin, and growth hormone pathways.

What Is Bikram Yoga?

Bikram Yoga is a branded yoga system created by Bikram Choudhury. It consists of a fixed sequence of 26 postures and two breathing exercises, always taught in the same order. The 90-minute classes are held in rooms heated to 105°F with 40% humidity. The sequence includes standing, balancing, and floor postures designed to work every part of the body. The heat is intended to promote flexibility, detoxification, and cardiovascular benefits. Bikram Yoga gained popularity in the 1970s and 1980s, but has faced controversy due to allegations of sexual misconduct against its founder. Despite this, many studios continue to offer the standardized Bikram sequence, often under different names such as "hot yoga" or "26&2 yoga."

Means also emphasizes that physical activity is crucial for maintaining a healthy metabolism. All types of physical activity benefit metabolic health and lower the likelihood of metabolic disorders. Walking 10,000 steps a day can reduce the likelihood of dementia by 50%, premature death by 50-70%, type 2 diabetes by 44%, and obesity by 31%. It also decreases the likelihood of cancer, mental health issues, acid reflux, and breathing disorders during sleep. Exercise improves the five fundamental indicators of metabolic health: blood sugar, HDL cholesterol, and triglycerides.

(Shortform note: The other two indicators are resting blood pressure and central obesity (measured at the waist). These five indicators are often grouped together because they’re all related to metabolic syndrome, a cluster of conditions that increase the risk of heart disease, stroke, and type 2 diabetes.)

It also improves the health of these cell structures, which is important for cell immunity and survival. In addition, exercise boosts insulin sensitivity, increases glucose tolerance, and lowers blood pressure. It also reduces body fat, such as belly fat. Insulin sensitivity is linked to muscle mass, so resistance training is important for metabolic health. As we age, our muscle mass decreases naturally, so it’s important to start resistance training early and maintain it as a lifelong practice. To increase your physical activity, Means recommends walking a minimum of 7,000 steps daily and building up to 10,000 daily steps. You should also get your heart rate to at least 60% of its peak for no less than 150 minutes weekly. Additionally, perform heavy lifting exercises several times weekly, targeting all primary muscles.

Federal Guidelines for Physical Activity

The recommendations to walk 7,000 to 10,000 steps daily, get your heart rate to at least 60% of its peak for 150 minutes weekly, and perform heavy lifting several times weekly are similar to the 2018 US federal guidelines for physical activity. These guidelines recommend at least 150 minutes of moderate-intensity activity per week, such as brisk walking, and regular muscle-strengthening activities. The guidelines were developed by a committee of experts who reviewed the latest scientific evidence on physical activity and health. They found that regular physical activity reduces the risk of chronic diseases, improves mental health, and enhances quality of life. The guidelines also emphasize the importance of reducing sedentary behavior and increasing overall movement throughout the day. The recommendations are based on the principle that some physical activity is better than none, and more is better for most health outcomes. The guidelines provide specific recommendations for different age groups, including children, adolescents, adults, and older adults. They also address special populations, such as pregnant women and people with chronic conditions or disabilities. The guidelines have been widely adopted by health professionals, fitness organizations, and public health agencies to promote physical activity and improve population health. They serve as a foundation for developing physical activity programs, policies, and interventions at the community, state, and national levels.

Bio-Observability & Tracking

Means explains that bio-observability lets you grasp your personal biology using technology. This involves using tech, such as wearables, continuous monitoring, and at-home lab tests, to watch your biology's processes. Bio-observability ranks among the top groundbreaking trends affecting the healthcare industry. You shouldn't place blind faith in your doctor. Instead, rely on your own body, which can "communicate" with you via easy-to-access tests and instant information from sensor wearables that enable you to comprehend how separate symptoms are linked to your general metabolic well-being.

Eric Topol’s Vision of the “Medical Selfie”

In 2015, cardiologist Eric Topol predicted that patients would soon be able to create “medical selfies” using their smartphones. He argued that continuous monitoring and at-home lab tests would allow patients to own their test data, eroding doctors’ monopoly on clinical information. Topol’s vision of patients using technology to understand their own biology anticipated Means’s argument that individuals should rely on their own bodies rather than placing blind faith in doctors. Both authors suggest that technology will fundamentally change how people relate to their own biology, empowering them to take a more active role in their health.

Tracking your health data may support living a healthier life, Means says. You can use technology to monitor your glucose levels, food intake, sleep, activity, and heart rate. This data can help you gain insight about your system and how your symptoms relate to your general health. You can use this information to decide what supports your health.

(Shortform note: To make the most of your health data, try this: Each evening, write down a single number from 1 to 10 for how you felt that day. Then, look at your glucose levels, food intake, sleep, activity, and heart rate for that day. At the end of the week, look for patterns in the numbers that line up with your best days. Use those patterns to make small changes to your habits.)