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Pillar 1: Body Science

The foundation — understanding how your body works.

🎯 Overview​

Body Science is the foundational pillar. Understanding how your body works at every level — from cells to systems — enables informed decisions about health and lifestyle.

Key question: "How does my body function?"

## 📖 The Story

Sarah and Jake both wanted to get healthier. They started at the same gym on the same day.

Sarah's approach: She followed whatever was trending on social media. One month it was keto, the next it was intermittent fasting at odd hours, then a new supplement protocol someone swore by. She'd try a workout program for two weeks, see minimal results, and switch to something else. When things didn't work, she blamed her genetics or assumed she was "broken." Three years later, she was frustrated, confused, and no closer to her goals.

Jake's approach: He spent the first month just learning. He read about how his cardiovascular system actually delivers oxygen, how muscles adapt to progressive overload, why circadian rhythms affect energy and recovery. When he tried intermittent fasting, he understood why it might work (circadian-aligned eating, metabolic switching) and could tell if it was working for his body. When he hit a plateau, he didn't panic — he understood adaptation and knew to adjust variables systematically. Three years later, he had a sustainable approach tailored to his physiology.

The difference? Sarah was flying blind, following rules without understanding. Jake had a map of how his body works.

The truth about body science: Understanding your physiology doesn't mean you need a biology degree. It means you can recognize patterns, identify root causes instead of chasing symptoms, and make informed decisions instead of hoping the latest trend works. When you understand why sleep affects muscle recovery, you prioritize it. When you understand how stress impacts digestion, you can troubleshoot gut issues. When you understand what happens during metabolic adaptation, you don't make counterproductive choices.

Body science is your owner's manual. You wouldn't try to fix a car without understanding how engines work. Why treat your body differently?

## 🧠 The Science

Core Concepts​

Body science encompasses the foundational understanding of how human physiology works — from the molecular level of cells to the complex integration of entire organ systems. This pillar provides the "why" behind health recommendations and the mechanisms behind bodily functions.

Key Systems:

  • Cardiovascular system — Delivers oxygen and nutrients throughout the body
  • Nervous system — Controls and coordinates all bodily functions
  • Musculoskeletal system — Provides structure, movement, and metabolic activity
  • Endocrine system — Regulates hormones and long-term processes
  • Immune system — Defends against pathogens and maintains health
  • Digestive system — Processes food and houses the microbiome
  • Respiratory system — Enables gas exchange and oxygen delivery
  • Integumentary system — Protects and regulates temperature

Why Understanding Matters:

  • Foundation for all other health decisions — Knowing how your body works helps you understand why nutrition, movement, and sleep matter
  • Explains how interventions work — Understanding metabolism explains why certain diets work; understanding circadian rhythms explains why timing matters
  • Helps troubleshoot health issues — When you understand the systems, you can identify where dysfunction might be occurring
  • Empowers informed choices — Knowledge of your physiology allows you to critically evaluate health claims and make evidence-based decisions
  • Reveals interconnections — Understanding how systems interact shows why holistic approaches are more effective than isolated interventions

🚀 Start Here​

Recommended reading order:

  1. Cells & Genetics — Start at the smallest unit; understand what you're made of
  2. Metabolism & Energy — How your body produces and uses energy
  3. Homeostasis — How your body maintains balance
  4. Circadian Rhythms — Your body's internal clocks
  5. Optimal Health — What thriving actually looks like

Then explore specific systems based on your interests or goals.

## 🚶 Journey

Your Body Science Learning Path​

Understanding your body is a journey that builds from simple concepts to complex integration. Here's a typical progression:

Month 1: The Basics (Foundation Building)

  • Understand what cells do and how they communicate
  • Learn the major body systems and their primary functions
  • Grasp basic metabolism: how you make and use energy
  • Recognize the importance of homeostasis and balance

Month 2: System Integration (Connecting the Dots)

  • See how cardiovascular and respiratory systems work together
  • Understand the gut-brain axis and immune-digestive connection
  • Learn how the endocrine system orchestrates everything
  • Discover how muscles affect metabolism beyond just movement

Month 3: Rhythms & Regulation (Timing & Optimization)

  • Master circadian rhythm concepts and their widespread effects
  • Understand how the nervous system controls automatic functions
  • Learn about hormonal cascades and feedback loops
  • Grasp how stress affects multiple systems simultaneously

Month 4: Advanced Concepts (Deep Understanding)

  • Explore epigenetics and how lifestyle affects gene expression
  • Study the hallmarks of aging and what influences them
  • Understand allostatic load and chronic stress effects
  • Learn about body composition beyond just weight

Month 5-6: Practical Mastery (Application & Personalization)

  • Connect body science knowledge to your specific health goals
  • Use biomarkers to track your body's responses
  • Identify your unique patterns and individual variations
  • Apply understanding to troubleshoot health issues

Ongoing: Refinement (Continuous Learning)

  • Stay updated on emerging research in areas relevant to you
  • Deepen understanding of systems most important to your goals
  • Experiment with interventions based on mechanistic understanding
  • Share knowledge and help others understand their bodies
Progression Tip

Don't try to learn everything at once. Master one system deeply before moving to the next. The interconnections will become clearer as your foundation strengthens.

💡 Key Principles​

Core Insights from Body Science

  1. Everything is connected — Your body is an integrated system, not isolated parts. The gut affects the brain, muscles affect metabolism, sleep affects immunity.

  2. You're constantly adapting — Your body responds to every input (food, movement, stress, sleep) by adapting. You're literally building a different body based on your lifestyle.

  3. Homeostasis is the goal — Your body constantly works to maintain balance. Health problems often stem from disrupted homeostasis.

  4. Circadian rhythms affect everything — Nearly every process in your body follows a ~24-hour cycle. Timing matters as much as the action itself.

  5. Aging is modifiable — While aging is inevitable, the rate and quality of aging are influenced by lifestyle choices.

## 👀 Signs & Signals

Body Indicators to Monitor​

Your body constantly communicates its state through observable signs and measurable signals. Learning to read these indicators helps you understand what's working well and what needs attention.

Cardiovascular System Signals​

  • Resting heart rate — Lower is generally better (50-70 bpm for healthy adults); tracks cardiovascular fitness
  • Heart rate variability (HRV) — Higher variability indicates better stress resilience and recovery
  • Blood pressure — Consistently <120/80 indicates healthy cardiovascular function
  • Recovery time — How quickly heart rate drops after exercise; faster = better cardiovascular health
  • Capillary refill — Press fingernail until white, release; should return to pink <2 seconds

Metabolic Signals​

  • Energy stability — Consistent energy without crashes suggests balanced blood sugar
  • Hunger patterns — Regular, predictable hunger indicates metabolic health; constant hunger or no hunger can signal issues
  • Body temperature — Consistently low temps may indicate thyroid or metabolic issues
  • Post-meal energy — Feeling energized (not sleepy) after eating suggests good metabolic flexibility
  • Fat distribution — Visceral fat (around organs) more concerning than subcutaneous

Nervous System Indicators​

  • Stress response — Quick recovery from stressful events indicates resilience
  • Sleep quality — Falling asleep easily and waking refreshed shows good nervous system regulation
  • Grip strength — Predictor of overall health and longevity
  • Balance — One-leg stand time correlates with neurological health
  • Pupil response — Reacts quickly to light changes indicates healthy autonomic function

Digestive & Immune Signals​

  • Bowel movements — Regular (1-3x/day), well-formed, easy to pass indicates healthy gut
  • Skin health — Clear skin often reflects good gut health and low inflammation
  • Wound healing — Fast healing indicates strong immune function
  • Illness frequency — Getting sick rarely (<2 colds/year) shows robust immunity
  • Bloating patterns — Persistent bloating may indicate gut dysbiosis or food intolerances

Musculoskeletal Signals​

  • Morning stiffness — Minimal stiffness (<5 minutes) indicates healthy joints and recovery
  • Muscle soreness patterns — DOMS (delayed onset muscle soreness) 24-48 hours after training is normal; immediate pain is not
  • Posture — Naturally upright posture suggests balanced muscle development
  • Range of motion — Full, pain-free movement in all joints indicates healthy musculoskeletal system
  • Muscle strength — Maintaining or gaining strength over time shows effective training and recovery

Hormonal Indicators​

  • Mood stability — Consistent mood suggests balanced hormones
  • Libido — Healthy sex drive indicates proper hormonal balance
  • Hair & nail growth — Strong, fast-growing hair and nails signal good thyroid function
  • Body composition changes — Difficulty losing fat or gaining muscle may indicate hormonal issues
  • Menstrual regularity — Regular, predictable cycles indicate hormonal health (for menstruating individuals)

Circadian & Sleep Signals​

  • Wake time consistency — Waking naturally at the same time indicates aligned circadian rhythm
  • Energy peaks — Clear morning energy peak suggests proper cortisol rhythm
  • Appetite timing — Hunger aligned with meal times shows good circadian regulation
  • Body temperature rhythm — Lower in morning, peaks afternoon, drops evening
  • Sleep latency — Falling asleep within 10-20 minutes is ideal
Tracking Tip

You don't need to monitor everything. Pick 3-5 key indicators most relevant to your current health goals and track those consistently. Patterns over weeks and months matter more than day-to-day variations.

📚 Topics​

Cellular Foundation​

TopicDescription
Cells & GeneticsHow cells function, DNA basics, epigenetics — how lifestyle affects gene expression
Tissues & StructureThe four tissue types and how they form organs and systems

⚡ Quick Wins​

Immediate takeaways you can apply today:

  1. Get morning light — Sunlight in the first hour sets your circadian rhythm for better energy, sleep, and hormone function

  2. Move throughout the day — Your body adapts to positions held for hours; break up sitting every 30-60 minutes

  3. Prioritize protein — Muscle is metabolically active tissue; adequate protein supports muscle maintenance and metabolic health

  4. Respect your sleep window — Your body has an optimal sleep time based on your chronotype; fighting it disrupts multiple systems

  5. Inflammation is a signal — Chronic low-grade inflammation underlies most modern diseases; anti-inflammatory lifestyle choices compound

## 📸 What It Looks Like

Real-World Applications of Body Science Knowledge​

Understanding body science isn't just theoretical — it directly informs practical decisions. Here's how this knowledge shows up in everyday life:

Scenario 1: Morning Energy Crash​

Without body science knowledge:

  • "I need more coffee to wake up"
  • Reach for sugary breakfast for quick energy
  • Wonder why energy crashes by 10am

With body science knowledge:

  • Recognize cortisol should naturally peak in morning (circadian rhythm)
  • Understand that morning light sets the circadian clock (photoentrainment)
  • Know that protein breakfast supports stable blood sugar (metabolism)
  • Action: Get sunlight within 1 hour of waking, eat protein-rich breakfast, delay coffee 90 minutes

Scenario 2: Plateau in Strength Training​

Without body science knowledge:

  • "I guess I've hit my genetic limit"
  • Keep doing the same routine expecting different results
  • Consider giving up or extreme measures

With body science knowledge:

  • Understand muscles adapt through progressive overload (muscular system)
  • Know that protein synthesis requires adequate stimulus and recovery (metabolism)
  • Recognize sleep is when muscle repair happens (circadian rhythms)
  • Action: Increase weight/volume gradually, ensure 0.8g protein per lb bodyweight, prioritize 7-9 hours sleep

Scenario 3: Persistent Digestive Issues​

Without body science knowledge:

  • "Some foods just don't agree with me"
  • Randomly eliminate foods based on trends
  • Treat symptoms with antacids

With body science knowledge:

  • Understand gut microbiome affects digestion and immunity (digestive & immune systems)
  • Know that food intolerances can indicate gut permeability (intestinal barrier)
  • Recognize stress affects gut motility via vagus nerve (nervous system)
  • Action: Food diary to identify patterns, stress management, consider probiotic foods, potentially work with professional for testing

Scenario 4: Difficulty Losing Fat Despite "Doing Everything Right"​

Without body science knowledge:

  • "My metabolism must be broken"
  • Cut calories even lower
  • Do more cardio

With body science knowledge:

  • Understand constrained energy model: body adapts total expenditure (metabolism)
  • Know that muscle mass affects metabolic rate (muscular system & body composition)
  • Recognize stress and poor sleep raise cortisol, affecting fat storage (endocrine system)
  • Action: Focus on strength training to build muscle, ensure adequate protein, prioritize sleep, manage stress, don't over-restrict calories

Scenario 5: Always Getting Sick​

Without body science knowledge:

  • "I just have a weak immune system"
  • Accept frequent illness as normal
  • Stock up on cold medicine

With body science knowledge:

  • Understand immune system requires adequate sleep for function (immune system & circadian rhythms)
  • Know that chronic stress suppresses immune response (endocrine system)
  • Recognize gut health directly affects immunity (digestive & immune connection)
  • Action: Prioritize 7-9 hours sleep, stress management practices, support gut health with fiber and fermented foods, ensure adequate vitamin D

Without body science knowledge:

  • "This is just what happens when you get older"
  • Accept declining energy, strength, cognitive function
  • Reduce activity to match perceived limitations

With body science knowledge:

  • Understand aging hallmarks are modifiable (aging)
  • Know that muscle loss (sarcopenia) accelerates without resistance training (muscular system)
  • Recognize that neuroplasticity continues throughout life (nervous system)
  • Action: Increase strength training, continue learning new skills, optimize sleep and nutrition, maintain social connections

Scenario 7: Afternoon Energy Slump​

Without body science knowledge:

  • "I need an afternoon nap or more coffee"
  • Push through with stimulants
  • Accept it as normal

With body science knowledge:

  • Understand natural circadian dip occurs early afternoon (circadian rhythms)
  • Know that large, high-carb lunches spike then crash blood sugar (metabolism)
  • Recognize that breaking up sitting improves energy and metabolic health (multiple systems)
  • Action: Smaller, balanced lunch; 10-minute walk after eating; brief movement breaks; strategic timing for cognitively demanding tasks
Pattern Recognition

The key skill body science teaches is pattern recognition: connecting symptoms to underlying systems, understanding root causes rather than just treating symptoms, and making informed interventions based on mechanisms, not just trends.

## ✅ Quick Reference

Body Science Essentials​

TopicKey Insight
HomeostasisBody constantly balances internal conditions (temperature, pH, blood sugar, etc.)
AdaptationBody changes in response to demands — you literally build yourself through lifestyle
Systems integrationAll systems work together; rarely does one system act in isolation
Individual variationGenetics and lifestyle create unique responses; what works varies by person
Circadian regulationNearly every process follows ~24-hour cycles; timing affects outcomes
Energy balanceMetabolism governed by intake, output, and efficiency; constrained energy model applies
Cellular foundationEverything starts at the cell level; epigenetics shows lifestyle affects gene expression
Use it or lose itMuscles, bones, brain all adapt to use; disuse leads to atrophy
InflammationAcute inflammation heals; chronic inflammation damages and underlies disease
Aging is modifiableRate and quality of aging influenced by lifestyle; hallmarks can be addressed
## ❓ Common Questions

Frequently Asked Questions About Body Science​

Q: Where should I start if I'm completely new to body science?

A: Start with three foundational concepts that underpin everything else:

  1. Metabolism & Energy — Understand how your body produces and uses energy. This explains why you feel tired or energized, how weight change happens, and why "calories in, calories out" is oversimplified.

  2. Homeostasis — Learn how your body maintains balance. This explains why extreme approaches rarely work long-term and why your body "fights back" against drastic changes.

  3. Circadian Rhythms — Discover how timing affects everything. This explains why when you eat, sleep, and exercise matters as much as what you do.

These three concepts explain the "why" behind most health recommendations and give you a framework for understanding the other systems. Once you grasp these, exploring specific systems (cardiovascular, digestive, etc.) based on your goals or symptoms makes much more sense.

Q: Do I really need to understand all this biology to be healthy?

A: You don't need to know every detail, but understanding the basics provides substantial benefits:

What you gain from body science knowledge:

  • Better decision-making — Understand why certain interventions work (or don't) for you specifically
  • Critical thinking — Evaluate health claims and fads based on mechanisms, not just marketing
  • Troubleshooting ability — When something isn't working, identify potential root causes rather than guessing
  • Personalization — Recognize that your unique physiology means you need individualized approaches
  • Long-term thinking — Make choices based on how your body actually works, not short-term fixes

The minimum effective dose: Understanding just the key concepts from each major system (cardiovascular, metabolic, hormonal, nervous) and how they interconnect gives you 80% of the practical benefit. You don't need a biology degree — you need enough understanding to make informed choices about your own health.

Think of it like driving a car: you don't need to be a mechanic, but understanding basics (how the engine works, why oil matters, what different dashboard lights mean) makes you a better, safer driver who can identify problems early.

Q: I don't have a science background. Will I be able to understand this?

A: Absolutely. These guides are written for general audiences, not scientists or medical professionals.

How we make body science accessible:

  • Plain language — Complex concepts broken down without jargon (and jargon explained when necessary)
  • Analogies — Abstract processes compared to familiar experiences
  • Visual aids — Diagrams, charts, and mermaid graphs illustrate relationships
  • Practical focus — Emphasis on "what this means for you" rather than technical details
  • Progressive complexity — Start simple, add detail gradually as understanding builds

Real example: Instead of "The hypothalamic-pituitary-adrenal axis mediates the stress response through cortisol secretion," we say: "When you're stressed, your brain signals your adrenal glands to release cortisol — a hormone that helps you respond to threats. Short-term, this is useful. Chronic stress keeps cortisol elevated, which disrupts sleep, increases fat storage, and suppresses immunity."

The goal isn't to make you a physiologist — it's to give you enough understanding to take control of your health decisions. If you can understand how a smartphone works at a basic level, you can understand how your body works.

Q: How does learning body science connect to actual health improvements?

A: Understanding mechanisms transforms how you approach health by revealing the "why" behind recommendations.

Concrete examples:

Scenario 1: Sleep struggles

  • Without body science: Try random tips from the internet (warm milk, counting sheep, sleep apps)
  • With body science: Understand that circadian rhythms are set by light exposure, cortisol should drop in evening, and core temperature needs to decline for sleep. Result: Get morning sunlight, dim lights 2-3 hours before bed, cool room temperature, avoid late caffeine. Actions based on mechanisms, not guesses.

Scenario 2: Weight loss plateau

  • Without body science: Assume "metabolism is broken," cut calories further, add more cardio
  • With body science: Understand constrained energy model (body adapts total expenditure), metabolic adaptation, and role of muscle mass in metabolic rate. Result: Focus on strength training to build metabolic tissue, don't over-restrict calories, prioritize protein and sleep. Sustainable approach based on how the body actually responds.

Scenario 3: Low energy

  • Without body science: Rely on caffeine and sugar for quick fixes
  • With body science: Investigate potential root causes — poor sleep quality (circadian misalignment?), blood sugar dysregulation (metabolic inflexibility?), thyroid issues (hormonal?), chronic stress (HPA axis dysfunction?). Result: Address root causes rather than symptoms.

The pattern: body science knowledge helps you identify mechanisms, which leads to targeted interventions rather than trial-and-error or treating symptoms while ignoring causes.

Q: Which body systems should I prioritize learning about?

A: Follow your symptoms, goals, or curiosity. Here's a decision framework:

Priority by symptom/concern:

If you're experiencing...Start with these systems...
Low energy, fatigueMetabolism, Circadian Rhythms, Endocrine (thyroid)
Difficulty losing fatMetabolism, Endocrine (hormones), Body Composition
Digestive issuesDigestive, Immune, Nervous (gut-brain axis)
Poor sleepCircadian Rhythms, Nervous (autonomic), Endocrine
Frequent illnessImmune, Digestive (gut microbiome), Sleep
Stress, anxietyNervous, Endocrine (HPA axis), Circadian Rhythms
Joint painSkeletal, Muscular, Immune (inflammation)
Exercise plateauMuscular, Cardiovascular, Metabolism
Brain fogNervous, Circadian Rhythms, Metabolism
Aging concernsAging (hallmarks), Cells & Genetics, all systems

Priority by goal:

  • Longevity → Start with Aging, then Cardiovascular, Muscular, Metabolism
  • Athletic performance → Muscular, Cardiovascular, Metabolism, Circadian Rhythms
  • Weight management → Metabolism, Endocrine, Body Composition, Digestive
  • Overall optimization → Start with foundational concepts (Metabolism, Homeostasis, Circadian) then explore systems based on your weak points

The interconnected reality: While you might start with one system, you'll quickly see how everything connects. Digestive issues relate to immunity; metabolism relates to circadian rhythms; hormones affect everything. Let your initial focus be a doorway, then follow the connections.

Q: How can I tell if my body's systems are working well?

A: Your body provides constant feedback through observable signs and measurable markers. Here are key indicators of well-functioning systems:

Signs of good systemic health:

Energy & Metabolism:

  • Stable energy throughout the day (no crashes)
  • Wake feeling refreshed
  • Regular, predictable hunger
  • Maintain muscle mass easily
  • Can go several hours between meals without feeling shaky

Cardiovascular & Respiratory:

  • Resting heart rate 50-70 bpm
  • Blood pressure <120/80
  • Can climb stairs without gasping
  • Heart rate recovers quickly after exercise
  • Good VO2 max for age (cardio fitness)

Nervous System:

  • Fall asleep within 10-20 minutes
  • Quick recovery from stress
  • Good balance and coordination
  • Sharp mental clarity
  • Appropriate stress responses (not overreacting or underreacting)

Digestive & Immune:

  • Regular bowel movements (1-3x daily), well-formed
  • Minimal bloating
  • Get sick <2 times per year
  • Wounds heal quickly
  • Clear skin

Musculoskeletal:

  • Minimal morning stiffness
  • Full range of motion in joints
  • Good posture without effort
  • Maintaining or building strength
  • Can perform daily activities without pain

Hormonal:

  • Stable mood
  • Healthy libido
  • Regular cycles (if menstruating)
  • Can build muscle and lose fat when appropriate stimulus applied
  • Strong hair and nails

Pro tip: You don't need to track everything. Pick 3-5 indicators most relevant to your goals and monitor those consistently. Trends over weeks and months matter more than daily variations. See the Signs & Signals section above for more detailed indicators.

## 🚀 Getting Started

Week-by-Week Learning Path​

Week 1: Foundation

Week 2: Systems

Week 3-4: Integration

Month 2+: Application

  • Apply knowledge to other pillars
  • Focus: Making informed decisions

🔗 Connections to Other Pillars​

PillarHow Body Science Connects
2 - NutritionDigestive system processes food; metabolism determines energy use
3 - MovementMuscular, skeletal, cardiovascular systems enable and adapt to exercise
4 - SleepCircadian rhythms regulate sleep; cellular repair happens during rest
5 - Stress & MindNervous and endocrine systems mediate the stress response
6 - EnvironmentExternal factors (light, temperature, toxins) affect all body systems
7 - GoalsUnderstanding physiology explains what happens during fat loss, muscle gain
8 - PersonalizationGenetic variation creates individual differences in response

🎯 Ready to Take Action?​

Now that you understand the foundations, apply this knowledge to your specific goals:

Your GoalStart Here
Lose fatFat Loss →
Build muscleMuscle Building →
More energyEnergy →
Better performancePerformance →
Improve health markersDisease Prevention →
Age wellLongevity →
Improve moodMind & Mood →

Browse all goals →

For Mo

When users ask about how their body works, physiology, or why something happens biologically:

  1. Start with the relevant system — Direct them to the specific body system involved
  2. Explain the mechanism — Use this pillar to explain the "why" behind recommendations
  3. Connect to their goal — Link body science to their practical objectives
  4. Acknowledge complexity — Bodies are interconnected; rarely is one system acting alone

Example: If a user asks "Why am I always tired?", explore: circadian rhythms, sleep quality, metabolic function, thyroid/endocrine, and how these connect to their lifestyle.

💡 Key Takeaways​

Essential Insights
  1. Your body is interconnected - Every system affects every other system
  2. Homeostasis is the goal - The body constantly works to maintain balance
  3. Stress is cumulative - Physical, mental, and environmental stressors add up
  4. Adaptation takes time - Changes happen through consistent signals over weeks/months
  5. Individual variation is real - Same inputs produce different outputs in different bodies

📖 Sources​

See Pillar 1 Sources for all references used in this section.

📊 Research Progress (click to expand)
TopicStatusNotes
Cells & GeneticsRound 3Enhanced: Epigenetics, epigenetic clocks, lifestyle effects
Tissues & StructureRound 2Basic coverage complete
CardiovascularRound 3Enhanced: VO2 max mortality research
MuscularRound 3Enhanced: Molecular responses, muscle memory
SkeletalRound 3Enhanced: Osteoporosis statistics and prevention
NervousRound 3Enhanced: Neuroplasticity research findings
EndocrineRound 2Basic coverage complete
ImmuneRound 3Enhanced: Trained immunity concept
DigestiveRound 3Enhanced: Microbiome as "virtual organ"
RespiratoryRound 2Basic coverage complete
SkinRound 2Basic coverage complete
Metabolism & EnergyRound 3Enhanced: Pontzer research, constrained energy model
Body CompositionRound 3Enhanced: Muscle mass mortality research
HomeostasisRound 3Enhanced: Allostasis detail, four types of allostatic load
Circadian RhythmsRound 3Enhanced: Molecular clock mechanism
AgingRound 3Enhanced: Epigenetic clocks detail
Optimal HealthRound 2Basic coverage complete
Common DysfunctionsRound 2Basic coverage complete