unit 1 quiz 1: nutrition and health Flashcards Preview

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Flashcards in unit 1 quiz 1: nutrition and health Deck (34)
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why do we eat food?

we need to

our brains and appetite

physiological reasons

physical influences and needs

Psychological Influences and Needs

social influences

emotional influences


why do we simply need to eat food

Food provides the fuel/energy/calories the body needs to survive.
Calories = energy we get from food, When people talk about the calories in food, what do they mean? A calorie is a unit of measurement — but it doesn't measure weight or length. A calorie is a unit of energy. When you hear something contains 100 calories, it's a way of describing how much energy your body could get from eating or drinking it.
Sugar is the easiest way to give your body energy, ex. Refined sugars, white sugar, corn syrup = high energy really fast.

Fatty foods = energy reserves, used to help when starving

Multiple bodily systems, like the circulatory, respiratory, neurological and endocrine systems, run automatically, and need energy to function.

So we are genetically programmed to eat when food is available as protection against starving, which would cause these systems to shut down.

Humans are hard-wired to eat fatty, sugary, high calorie foods because they have the most energy

More energy = a better chance of survival.


what does eating have to do with our brains and appetite

Neural receptors in the brain receive hormones like ghrelin & leptin into the brain which can regulate appetite.

Ghrelin, produced in the stomach that tells us when to eat.
tends to be released on a schedule
can be triggered by smells
blood levels of ghrelin tend to be highest before mealtimes, and return to low levels after mealtimes.
Leptin - hormone made by adipose cells

Cholecystokinin (CCK) is produced in the stomach and upper intestine to alert the brain to feeling full.
Triggered by sensors/receptors in the stomach, goes to the brain and other parts to say to start digesting food.

It sends a short term message to the brain telling us to stop eating through stimulates the vagus nerve

The vagus nerve extends from the brainstem and is involved in the control of several bodily functions, including digestion.

Leptin is produced by adipose tissue, or body fat.
helps regulate the body’s energy, in the form of fat stores, over the longer term.
does not have as direct of an impact on food intake from meal to meal as ghrelin
Counters ghrelin (as it can suppress appetite)
Hungry- Ghrelin (high) Leptin (low) Full- Ghrelin (low) Leptin (high)


why do we eat for physiological reasons

Genetics- We are programmed to eat!
maintain health
genetic preferences (sensitivity to taste)
Lifestage - Nutrient needs vary at particular stages in life
Body of the mother produces fats and sugars in breast milk for babies.
Really old people need calcium, fibre.
Adolescents need diversity of fats and nutrients for the brain.


why do we eat for physical influences and needs

Availability of resources
Availability of food
Geography, climate, soil, water
farming technology
transport & storage of food
political stability
store location
Income level/education level
Time (for food prep.)
Skill level (comfort in preparing food)


why do we eat for Psychological Influences and Needs

Sense of security
comforting to know you have food
can create a feeling of being cared for
Someone wanting to eat with you, dates, parties, etc.

Sense of belonging
creates a social bond between people
welcoming visitors, celebrations, life events

Sense of providing/taking care of others
sense of contributing to the family or group
enjoyment in fulfilling other people’s needs (nourishing people)
making others feel happy and welcomed/belonging
Bringing bottles of wine, food, gift cards, etc.


what do social influences have to do with why we eat

Culture → Beliefs & customs of a group of people
Religious influence
Traditions (historical & seasonal)
Ex. pumpkin spice lattes, seasonal corn, large meals for special occasions
Ethnicity-common blood, land, race
Food norms (eggs & bacon for breaky)
Food taboos (not eating certain foods)
Ex. health reasons, mental health reasons, religious reasons, certain diets

Family (which is influenced by the culture)
Values, beliefs, attitudes & traditions
Lifestyle (single parent? Working?...)
Preferences (of members)

Peers - eat similar foods
good & bad influence
often socializing includes food

Media - ads, TV, internet, social media, coupons, samples


what do emotional influences have to do with why we eat

mood and stress levels connecting to food
Memories (positive/negative connected to food)
Comfort food


eating is a ____ experience

multi sensory


what senses are involved with food?

- Visual effect of food
- Feel of the food in our mouth - crunchy, smooth
- sound of the food in our mouth - expectation of how something will taste vs. reality
- flavour of the food - taste, smell, feel, surrounding environment/atmosphere
- surrounding environment or atmosphere.


taste and smell are ......

survival mechanisms
– a way to test food or other substances before they enter the body.
Evolution is very prominent in these ideas. When we taste sour or spicy foods enter our mouths, it could be bad for us ex. Plant hormones, sour/spoiled food.
Sugary foods = good source of quick energy, we know it since it tastes sugary and we know what sugar does.
Bitterness -

Bitter and sour = could mean poison
Sweet = high energy carbohydrates
Salty = essential minerals
We need salt, used for electron balancing for neurons
Umami (savoury ex. Meats, cheeses, mushrooms, broths) = protein/ fat (long term energy stores)
We like these because proteins are long term energy storers in case of starvation.


what % of our taste is actually smell?

Smell helps us detect - dangerous odors
- ripe and rotten fruit.
95% of what people describe as “taste” is actually our sense of smell
Our true taste sense happens only in the mouth


how does taste work?

The surface of the tongue is covered with papillae
Papillae contain taste buds - not the bumps on our tongues, but inside our tongues, those are papillae
Taste buds contain taste Taste Receptor Cells (TRC)
TRC have tiny openings called taste pores that contain “taste hairs”
“taste hairs” react to 5 different tastes: they have all taste receptors inside of them
- sweet
- salty
- sour
- bitter
- umami (savory)
Chemicals from food dissolve in our saliva before they enter the taste pores and are detected by the taste hairs
Breaking down food in mouth allows food to communicate with taste hairs.
Taste signals travel through nerve pathways up the brainstem to the gustatory complex (area responsible for perceiving taste, not smell). Taste pathway (TRC to nerves to brain, up the brainstem and to GC).


how does smell work?

Olfactory receptors detect scent molecules in the air and send signals to the olfactory bulb in the front of the bulb.
Not 5 different tastes, like a million scents in our environments
Aromatic - gives off a strong smell, ex. Garlic,
Olfactory bulb is enveloped by the emotional area of the brain, The Limbic System making a very strong connection between scent and memory.
The Limbic system is our emotions and long term memories are. Scent and memory are very closely related.
Can protect us, ex spoiled milk scent.


how does our sense of touch play a part in our tasting experience?

Sensing spice, temperature & texture
Signals are sent along the trigeminal nerves responsible for sensations in the face and mouth.


what happens when taste, smell and touch come together?

The 3 distinct nerve pathways:
Taste smell touch
all meet in the prefrontal cortex where we perceive flavour


what is flavour?

Flavour is a combination of smell, taste, texture, temperature
Other factors that affect flavour are:
taste, smell, spice, texture, temperature setting, your mood, emotional, past experiences with that particular food item, and your genetic sensitivity to tastes.


define digestion

Digestion: the process of breaking down food in the digestive system so the body can use it as energy to maintain systems, functions, grow and fight disease.
There are two types of digestion
Physical digestion → using movement to physically break down food into smaller pieces
Chemical digestion → using enzymes to chemically break down food into simple forms that the body can absorb and use


the digestion process begins in the...

- Food is physically broken down by chewing or mastication.
- Saliva moistens the food and chemically breaks it down with enzymes produced by the salivary glands.
- After being chewed and swallowed the food is now called a bolus.


what occurs in the esophagus?

food is swallowed and enters the esophagus.
- a long tube from the mouth to the stomach.
- uses rhythmic, wave-like muscle movements (called peristalsis) to force food from the throat into the stomach.


what occurs in the stomach?

a muscular pouch on the left side inside the rib cage (holds 4 cups of food)
- Churns the food (using peristalsis) in hydrochloric acid (only in the stomach) & enzymes like protease (chemically break it down).
- Food in the stomach is now called chyme (hydrochloric acid and enzyme smoothie).
Turns food into slushy food juice, then chyme goes into the small intestine.


what occurs in the small intestine?

key player in digestion, where chemical digestion starts
- has 3 parts: the duodenum, jejunum and ileum.
- food (chyme) enters the duodenum (a little at a time),
- Bile (produced in liver and stores in the liver and in the gallbladder), pancreatic enzymes, and other digestive enzymes produced by the inner wall of the small intestine help in the breakdown of food.
- About 90% of all digestion occurs in the small intestine
-95% of all absorption occurs in the small intestine

- most absorption of nutrients takes place in the small intestine
- lining has many tiny folds containing villi that allow more nutrients to be absorbed because of the increased surface area of the villi.


enzymes and what they do

break down different foods:
Amylase - breaks down carbohydrates into simple sugars like glucose (begins in the mouth)
Protease - breaks down proteins into amino acids (building blocks of proteins) which can be used to make new types of proteins for example new skin cells, hair, etc. (begins in the stomach)
Lipase - breaks down fats into fatty acids and glycerol which are stored in adipose tissue, or body fat (begins in the mouth). Used for energy sources if needed.


what occurs in the large intestine?

(also called the [large] colon) Last chance for the body to absorb stuff before it leaves and make fecal matter less watery, if you don’t have a condition. Too much water - diarrhea, not enough - constipation
- Absorption of some water, vitamins & minerals (eg. electrolytes like potassium and sodium) from the waste.
- Soluble fibre is broken down but not absorbed.
- microbial bacteria help in the digestion process.
- remaining waste is stored in the lower intestine (rectum) until eliminated


how do we process and store nutrients?

Villi in the small intestine absorb the nutrients and carry it through a blood vessel (portal vein) to the liver
- Liver turns nutrients into usable forms for the body
- e.g. amino acids are turned into proteins and carried through the blood
- Some nutrients are stored for later use
- e.g. glucose is turned into glycogen and store in liver and muscles
- if there is more glucose that can be stored as glycogen, it is turned into body fat
- Minerals are stored in various ways
- e.g. iron is stored in liver
- Fat-soluble vitamins are stored in liver and in fat (Vitamins A D E & K)
- Water-soluble vitamins are not stored, if they cannot be used right away then they are excreted as waste


how are nutrients used?

How Nutrients are Used
- Nutrients and oxygen are carried through the bloodstream to cells to provide energy through cellular respiration
- Glucose (chemical energy from food) combines with oxygen to create a new form of energy that can be used to power the cells
- In this process, water and carbon dioxide are also made, but are excreted or exhaled as waste
- Body uses energy for automatic processes (breathing, digesting, circulating blood, creating new cells) and physical activity (work, exercise)


Cellular respiration formula

glucose + oxygen turns into water, co2 and atp

atp is used for energy and the co2 and water are expelled by breathing out and pizzing/shidding


how do our eating habits affect our digestion and how can we fix it?

- Too little food or a diet lacking variety = missing nutrients
- High fat foods take longer to digest (leave the stomach last)
- Lacking a single nutrient affects absorption of other nutrients (eg. vit. C helps absorb iron)
- Eating too fast or too much stresses digestion
- Eating spoiled or contaminated food
- Eat a nutritious diet with lots of variety
- Lots of fruits & vegs, & whole grains with fibre to aid digestion
- Eat moderate amounts, watch portion sizes
- Eat slowly, in an unstressed mode
- Be aware and mindful while eating so not to overeat
-Be aware of food safety


how can our emotions/feelings affect our eating habits and how can we fix them?

We can eat irrationally and unhealthily. Imagine going through a breakup. You probably won't reach for spinach and kale, but maybe a tub of ice cream or some candies. These are all fine in moderation but don't forget to eat in variety and moderation to feel your best.

- Eat slowly
- Eat in a calm, quiet environment
- Use exercise & meditation to reduce stress
- Time management
- Other individual positive coping strategies for negative emotions


how is physical activity good for us and our digestion?

- Helps digestion by moving food through GI tract
- Helps metabolism by increasing rate of waste expulsion through breathing and sweat
- Stimulates appetite
- Strengthens muscles of internal organs
- Makes you feel good - releases endorphins (”feel good” hormone) from the brain