deeilna

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all of nutrition science

13 min read

source link: https://www.youtube.com/watch?v=QVgeB5iWcBc | Dabby

surprisingly such a complete resource!

“Nutrition explained from first principles. This video breaks down digestion, macronutrients (carbs, fats, protein), micronutrients (vitamins and minerals), gut health, metabolism, hormones, and why ultra-processed food breaks biology. All of this, without the BS.”

Table of content

What even is nutrition

  • nutrition = your body extracting nutrients and using them
  • nutrients = things your body cannot produce by itself
    • = “molecular building blocks”
    • such as, carbs, proteins, fat, AND vitamins, minerals

Your body is a food-processing factory

  • your body = machine running the food-processing factory : )

Digestion explained: mouth to stomach

  • starts with mouth = built-in grinder + salivary enzymes = digestion step 1 (demolition pt1)
  • mouth → stomach = acide tank = digestion step 2 (demolition pt2)
    • protein and fat get broken down by enzymes, bacteria get killed, and basically food turns into “usable mush” that you gut can use to absorb mineral, nutrients

Small intestine, absorption, and villi

  • stomach → small intestine = absorption zone
  • pancreas releases biochemical scissors (enzymes) that cut nutrient (carbs, prots, fats) into absorbable pieces
  • this is where your body absorbs the nutrients, w/ the villi and micro-villi = microscopic absorption carpet (see it as the micro-fiber towel that absorbs water)
  • absorbed nutrients go to the liver

The liver: nutrient control center

  • nutrients → liver = command center for nutrients
    • every molecule reports to the liver first before entering the blood stream
    • 4 options: burn it, store it, detox it, send it elsewhere

you are not what you eat,
but you are what you absorb

Macronutrients overview

  • 3 macronutrients = carbs, fats, proteins
    • = body needs them in LARGE QUANTITIES
  • vs. micronutrient = vitamins and minerals
    • = body needs them in small quantity

Carbohydrates and glucose

carbohydrates = body’s preferred fuel

  • every carb is transformed into the same molecule = glucose
    • carbs → glucose
  • with glucose, there are only 2 options for the body
    1. immediate energy
    2. glycogen storage (= stored glucose in the liver and muscles, for a later use)
  • however, glycogen tanks are small
    • the extra glucose that cannot be stored in the tanks ⇒ converted into body fat
  • but there are different types of carbs
    • depends on how they are built, ie their molecular structure,
    • thus how fast they enter your bloodstream
Simple vs complex carbs and fiber
  • simple carbs = tiny chains ⇒ instantly digested ⇒ fast blood sugar spike ⇒ fast crash, hunger
  • complex carbs = long and tangled chains (complex duh) ⇒ slow digestion, slow glucose release ⇒ slow energy, keeps you full longer
  • fiber = carbs that body cannot digest, but gut bacteria feed on it ⇒ keep your gut healthy and smooth transit and SLOW DOWN glucose absorption ⇒ prevent blood sugar spike

Fats are not the enemy

  • brain = 60% fat
  • fat is also essential for cells, hormones

fat is not an enemy, it is essential
fat = transport system (logistics) that allows body to absorb nutrients and vitamins (A, D, E, K)

  • but again, healthy fats vs. unhealthy fats depends on molecular structure
  • which determines how body uses them
Types of fats explained
  • saturated fats = eg butter or coconut oil
    • they are solid in room temperature, chemically stable ⇒ high heat tolerance ⇒ good for cooking
    • but fine in moderation only
  • unsaturated fats
    • mono unsaturated fats = eg olive oil
      • liquid, but still stable
      • the standard for everyday fats and heart health
    • poly unsaturated fats = eg omega-3s and omega-6s
      • multiple double bonds, liquid, fragile ⇒ oxidise easily, cannot tolerate high heat or heavy processing
      • they are needed by the body
      • omega 3s: helps reduce inflammation
      • omega 6s: helps create inflammation for healing

tldr; the ratio omega 6 to omega 3 is what matters
a good ratio = 1:1 to 1:4 (ie more o3!)

Why trans fats are harmful
  • trans(formed) fats = artificial and harmful because of their unnatural structure, created by hydrogenating oils ⇒ structure becomes rigid, body cannot process ⇒ messes up with body
    • lowers good cholesterol, increases bad cholesterol
    • increase inflammation
    • promote artery plaque
  • found in transformed and processed food!

avoid trans fats as much as possible

Protein and body structure

  • every cell in your body is made of protein (muscle, organs, skin, hair, nails)
  • there is no storage tank for protein, unlike for carbs and fats
    • so if there is deficiency, your body will steal protein from muscles, hair, nail, etc.
    • to keep your heart beating : O
  • proteins in your body:
    • enzymes = proteins that digest the food
    • hemoglobin = proteins that carries oxygen from lungs to cells
    • antibodies = proteins that fight off invaders (viruses, bateria)

protein = actual structure of your body + repair of body

Essential amino acids and protein quality

protein is built from 20 lego bricks = amino acids
- 9 are essential = body cannot make them
- 11 are non-essential = body can manufacture them

  • if just 1 of the 9 essential amino-acids is missing, protein factory stops, meal = just carbs and fat
    • ⇒ protein synthesis = all-or-nothing
  • so… protein quality matters
    • ⇒ animal protein = complete protein, have all amino-acids ⇒ easier for body to use
    • vs. plant based protein = (usually) incomplete protein ⇒ body doesn’t use as efficiently
  • but diversity also matters!
    • some legumes (peas, beans) can be high in some, and low in other amino-acids
    • ⇒ you can combine them to fill up the gaps
Muscle growth, leucine, and protein timing
  • to activate muscle protein synthesis, not only do you need complete protein…
    • but body needs enough of 1 amino acid specifically = leucine
    • when enough leucine from a single meal ⇒ muscle growth process turns on
    • if not enough leucine ⇒ muscle growth process doesn’t happen
    • enough ~ 30g protein at once >>> smaller amounts throughout the day won’t be enough to activate the process
  • protein has a higher thermic effect
    • ie body spends more energy to digest it, ie burns more calories to digest it
Protein intake: minimum vs optimal
  • recommended protein intake per day depends on body weight and level of activity
    • sedentary = 0.8 - 1.0 grams per kg ⇒ 1.0g/kg
    • active = 1.2 - 1.6 grams per kg ⇒ 1.5g/kg
    • muscle building = 1.6 - 2.2 grams per kg ⇒ 2.0g/kg
    • fat loss (calorie deficit) = 1.8 - 2.4 grams per kg ⇒ 2.2g/kg
    • so if you’re 60kg, and you’re active, aim for 90g of protein per day

How food becomes energy (ATP)

  • food doesn’t become energy instantly, it gets processed

energy in food is measured in calorie = unit

  • carbs and fats enter blood stream directly as raw materials
    • they are delivered to the mitochondria (the powerhouse of the cell)
    • inside the mitochondria: carbs and fats ⇒ converted to ATP (a molecule that carries energy) = literally what your body uses to stay alive, or to move
    • BUT mitochondria needs micronutrients to do that
      • micronutrients = vitamins and minerals

Metabolic flexibility and fat burning

  • healthy metabolism = hybrid engine that uses 2 sources of fuels, can switch between them depending on what’s available
    • glucose / sugar
    • fat
  • sugar burning mode:
    • when you eat ⇒ glucose / sugar in blood is high, plenty available (but high sugar is also damaging)
    • ⇒ body burns this sugar first
  • fat burning mode:
    • only when no more sugar ⇒ the switch is flipped
    • ⇒ body burns stored body fat

⇒ metabolic flexibility = body switches between those 2 sources of fuel ⇒ GOOD

  • but if snack all day ⇒ sugar tank replenished all day ⇒ body never switches to fat burning mode ⇒ BAD!

Vitamins and minerals explained

  • micro-nutrients = vitamins and minerals, which are non-caloric nutrients
    • ⇒ they do not provide energy, cannot be converted to ATP (eg salt or water doesn’t give you energy)

micro-nutrients don’t provide energy, but they allow the production of energy to happen

  • non-caloric nutrients = water and micro-nutrients
    • water = 2L per day, no questions
  • vitamins: there are 2 types, depending on how long your body keeps them
    • fat soluble vitamins = A, D, E and K
      • they stick around in your liver and fat for weeks, or months ⇒ you can store them for a longer term, no need to refuel everyday
      • they all handle different jobs
        • vitamin A: night vision & eye health, fights infections, keeps skin healthy
        • vitamin D: helps absorb calcium & phosphorus for bone density, immune support
        • vitamin E: powerful antioxydant that protects cells from damage, stops blood clots from forming
        • vitamin K: puts calcium in your bones (not your arteries), clots the blood when you get a cut
      • they need FAT to be absorbed!!!
    • water soluble vitamins: B-complex and C
      • they come in, do their jobs and leave through pee ⇒ you need to refuel regularly
      • they also handle different jobs
        • B-complex vitamins: help cells turn food into ATP, keeps nerves working fast, make chemicals that control mood and sleep, make new red blood cells and gut lining
        • vitamin C: build strong collagen to keep skin firm and body from falling apart
  • minerals: raw elements from the earth
    • electrolytes: sodium, potassium, magnesium
      • control electrical signal and fluid balance
      • keeps muscle contraction + nerve communication
    • builders: calcium, phosphorus
      • = materials used to build bones and teeth
    • catalysts: iron, iodine, zinc
      • body’s specialised tools
        • iron = carries oxygen in the blood
        • iodine = fuels thyroid hormones
        • zinc = triggers reactions that help cells grow and heal

Gut health and the microbiome

  • everything gets processed in the gut = tube from mouth to butt = your second brain in fact
    • contains millions of neurons and constantly chats with actual brain
    • influences mood, craving, immune system
  • inside the gut (this tube) is the microbiome = trillions of micro-organisms (bacteria)… both good and bad
    • good gut: goal is to maximise the good bacteria, through environment and food
      • namely with fermented food = contains probiotic = live beneficial bacteria = they are the seeds
      • prebiotics = fiber that probiotic (bacteria) consumes! it’s the fertiliser
      • the probiotic bacteria will make SCFAs (short-chain fatty acids) = lower inflammation and keep colon cells alive = basically gut fuel and protection!
    • bad gut: if you starve the good bacteria, or constantly irritate the gut with stress or processed food
      • gut layer (protective mucus wall) becomes weak ⇒ bad bacteria and toxins can penetrate into your bloodstream ⇒ “leaky gut”, your immune system goes to war
      • can also trigger cellular breakdown… damage

Cellular damage: inflammation, oxidation, glycation

  • cellular breakdown happens in 3 distinct ways
    1. inflammation = fire
      • can be acute: first responder to heal a cut, or repair a muscle
      • can be chronic: wild fire that never goes out, slowly burning down healthy tissue
    2. oxydation = rust
      • your body produces oxydation naturally, but without antioxydants to filter them ⇒ your cells literally rust ⇒ damages DNA
    3. glycation: gunk
      • this happens when excess sugar binds to protein or fat ⇒ “caramelises” them by creating a toxic, sticky compound called AGEs (Advanced Glycation End-Products) that makes tissues stiff and brittle
      • ⇒ main cause of winkles and stiff joints

Hormones: insulin, dopamine, cortisol

  • how does the body repair cellular damage???
    • depends on your hormones, such as insuline
  • insuline = pancreas releases this hormone, this lets sugar to penetrate your cells
    • when you eat ⇒ insuline switch flips on, insuline is high ⇒ body focuses on storing energy >>> clean up process is blocked
    • when you don’t eat for a while aka FASTING ⇒ insuline drops ⇒ body switches to autophagy mode ⇒ clean up process activated, cells eat their own broken parts
  • the problem nowadays: insuline switch is stuck ON
    • … normally, it shouldn’t because your body has a fuel gauge to tell when you’re full vs. hungry
    • but dopamine (reward) highjacks that sensor
      • → ignore stop signals (= Leptin & GLP-1 = “stop eating” signals)
      • → make you hunt for rewards (junk food, or just food)
    • and cortisol = stress alarm
      • → stress = body thinks you’re in danger (like running from a predator)
      • ⇒ body literally melts down your muscle tissue to dump massive energy into your blood for you to sprint
      • so… you just loose your muscles, while that unused sugar settles in your fat tissues (your tummy)

Ultra-processed food and modern biology

  • modern food engineering overpowers ancient biology nowadays :(
  • in nature, macronutrients are usually separated
    • fruits = sugar, but not fat
    • meat = protein and fat, but not sugar
  • but ultra-processed food are different,
    • they are industrially formulated to hit a mathematically perfect bliss point (processed fats, refined sugar, intense salt)
      • flavour persistence, reward spike, fast energy + creamy texture
    • ⇒ this structure short-circuit the brain stop signal, mimicking the rapid dopamine hit of a drug vs. slow satisfaction of a meal
  • even more (further “engineered”):
    • injection of sneaky substances into the food:
      • preservatives: stop bacteria from multiplying to extend shelf life → consumed, they also suppress your good bacteria in your gut :(
      • emulsifiers: binding agents to keep food from separating → consumed, they act like gut soap and damage your gut lining (protective wall), reduce the SCFAs (gut fuel) ⇒ leaky gut

simple rule to remember and follow:
if a food didn’t exist 200 years ago, try to avoid it

The 4-step nutrition strategy

  • now how to actually eat healthy and fix the machine? : D
  • 4 steps:
  1. cut the crap (focus on real food intake)
    • basically remove the processed food from your diet following

the 1 ingredient rule: the best food don’t have ingredients, they are ingredients

  1. lock in the foundation (ie focus on protein)
    • once the junk is out, define the new goal = shut down hunger and protect muscles
    • why this goal? because protein = most satiating nutrient, if you focus on that you’ll have less room for junk, you’ll feel full longer
    • how? don’t count calories <<< count protein and aim for solid portion at every meal based on your body size
  2. adjust the energy dials (adjust carbs/fats based on activity)
    • protein = foundation, should stay fixed
    • carbs + fats = dials you turn based on lifestyle
      • sedentary → lower carbs, and rely on healthy fats for stable power
      • active → turn up the carbs
  3. fill the holes (supplements only when necessary)
    • ie optimisation with supplements = in addition to your diet >>> not substitute or replacement
    • in fact, bioavailability matters:
      • natural food = packages nutrients + food your body needs to absorb them efficiently
      • pills = isolated chemicals → not easy to absorb
    • need blood work to identify what is needed, not just random pills