PhySci 5 Midterm 1 - UCLA Esdin

Lifestyle diseases examples

heart diseases, diabetes, blood pressure, certain forms of cancer, digestive and respiratory disorders, etc.

What are lifestyle diseases?

Related to a specific behavior we are doing.

How do we know if someone has a lifestyle disorder?

Not just one problem. Spills over to become not just diabetes but multiple diseases

#1 killer disease in US and worldwide

Cardiovascular diseases

Obesity

excessive accumulation of body fat. Not a disease. A marker, indication of disease. Tells us if someone is at risk of CVD, diabetes, hypertension

How do you measure obesity?

Waist circumference, body fat percentage, BMI, DEXA

Body fat percentage

Amount of body fat person has in relation to muscle. Talking about excessive fat in certain locations

BMI

weight (kg) / height (m^2)

DEXA

dual-energy x-ray absorptiometry. Measures visceral (correlated w health problems) vs subcutaneous fat (fat stored just beneath skin)

Measures bone density and measures fat. Gives you visceral fat % and breaks fat % down for each body part

Obesity defined by waist circumference

Males: 102cm or 40 inches

Females: 88cm of 35 inches

Obesity defined by body fat percentage

Simple scale w metal that sends electrical current through body. Electricity travels well through water but not through fat. Based on this, you get a percentage.

Males: 25%+ is considered obese

Females: 30%+ is considered obese

If you are dehydrated you will have a ______ body fat %

higher

if you drink a lot of water before measuring body fat % you have ______ body fat %

lower

Obesity defined by BMI

18.5-24.9 = normal

25-29.9 = overweight

30+ = obese

Obesity in Children

At risk for overweight: BMI of 85-95th percentiles

Actually overweight children:

BMI for age is greater than or equal to 95th percentile (2+ yrs old)

Is waist circumference or BMI a better indicator of obesity?

Waist circumference. High WC ratio is assoc. w diabetes, hypertension, dyslipidemia

Dyslipidemia

High amounts of fat in blood

Why is obesity not easily controllable?

It is a hormonal imbalance. Our appetite is controlled by our hormones. Not necessarily something people can control

Complications of diet and exercise

Economic and convenience

Leading causes of death in 2020

Heart disease, cancer, COVID-19, Accidents (unintentional injuries), stroke, chronic lower respiratory diseases, Alzheimer's disease, diabetes, flu and pneumonia, nephritis, nephrotic syndrome, and nephrosis

What is the correct formula to measure BMI?

weight in kg/height in m^2

Which of the following is the most accurate method to measure fat composition?

DEXA

3 multiple choice options

Nutrition

The science of food, the science of digestion, the science of absorption, the science of metabolism, the science of storage

the science of digestion

Breaking down the food. When you swallow food, it becomes inside your body a lot later, when energy from food is available to every cell in the body. Digestive organs are like temporary holding spots for food. Purpose of digestion is to break food down from large to small-sized molecules. How long is takes is determined by the types of food we are eating. Rule: something that will take longer to be digested will keep you full for longer

the science of absorption

when your cells have access to the food you ate. when food molecules are in blood circulation. dependent on digestion. slower digestion --> slower absorption

the science of metabolism

is this molecule involved in a chemical reaction that will make it harmful or beneficial for me?

the science of storage

we constantly need food energy. we store stuff in liver, muscles, and fat cells. It is more advantageous for us to store stuff in our muscles.

Food

whatever you are eating. different from nutrition

Wellness

the absence of disease

Osteoporosis

Disease partially affected by nutrition. weakening of the bones. Throughout their lives, the elderly with this did not consume enough vitB or calcium. However, not everyone with these deficiencies gets osteoporosis/not everyone who consumes these sufficiently doesn't get osteoporosis

Diseases Highly Affected by Nutrition

Heart diseases, diabetes, lifestyle diseases in general

Diseases affected by nutritional deficiency or toxicity

consuming too little or too much vitamins. Anemia, pellagra

Anemia

low iron

pellagra

Niacin deficiency

Healthy People 2030 Goals and Objectives

Pricing strategies and edu interventions in schools may help people lmit foods and drinks with added sugars

Veggies are recommended as a key part of a healthy diet, and eating vegetables is linked to a lower risk for many diseases

Essential Nutrients

Macronutrients & micronutrients & water

Macronutrients

carbs, lipids, proteins

micronutrients

no calories. vitamins & minerals

Carbohydrates

Energy: 1g=4cal

Some are good, some are bad

Many types

Source of short-term energy

We can technically get by without consuming these, but the problem is that carbs are in pretty much everything and they are your cells' preferred energy source

Come from plants and animals

Lipids

1g=9cal

Good and bad

Many types

Longer energy source (digestion takes longer --> absorption takes longer)

We cannot get by without consuming these

Proteins

1g=4cal

Good

Many types

Many functions

Cannot get by without consuming these

Pellagra is due to

Niacin deficiency

T or F: Movement of the food from the digestive organ into the blood is called digestion

False

Vitamins

Not an energy source. Important for metabolism.

Fat soluble vitamins

A, D, E, and K. Stored in the body

Water soluble vitamins

Bs and C. Not stored in the body

Minerals

Sodium (does not raise bp but for ppl with high bp, sodium can negatively influence), Potassium, Magnesium, Zinc, Iodine (very important for metabolism - lack of iodine assoc. w disease)

Water

inorganic essential nutrient. Involved in many body processes including fluid balance, nerve impulses, body temperature, muscle contractions, nutrient transport, excretion of waste products

What % of your body is water?

60%

What % of your blood is water?

90%

Causes of death in 1911

Pneumonia and influenza, tuberculosis, diarrhea and enteritis, diseases of the heart, senility and vascular legions, nephritis, cancer, diphtheria (upper respiratory tract)

Acute diseases

Have a clear cut beginning, middle, and end. Amenable to the one shot solution (contamination of water --> sanitation, polio --> vaccination) Used to be more common bc there wasn't good sanitation. When they happen, they affect a lot of individuals in the population.

Chronic diseases

Begin early in life long before clinical symptoms appear. Early detection is needed. Not cured, but managed. We call these lifestyle diseases. Not every chronic disease is a lifestyle disease but every lifestyle disease is a chronic disease

Risk factors of cardiovascular diseases

Tobacco, lipids, hypertension, physical inactivity, diabetes, obesity, diet, alcohol, stress

Tobacco as a Risk Factor

Inflammation. Tobacco products have carcinogens which harm your body. Carcinogens causing inflammation will lead to prolonged inflammation. Overuse of immune system --> major effects on CV system

Carcinogen

any chemical that does not sit well with your body

inflammation

immune system active extensively

Lipids as a Risk Factor

fat is not bad. certain types are bad. main one: Trans fat. Used to be used a lot as a food stabilizer/longer shelf-life inducing product. Vegetable oils - specifically soy oil

Hypertension as a risk factor

Makes blood vessels unstable. High Blood pressure: 140+ systolic or 90+ diastolic

systolic pressure

Blood pressure in the arteries during contraction of the ventricles

diastolic pressure

Blood pressure that remains between heart contractions

Diabetes

Inability for body to manage sugar. Out body has a thermostat: blood has normal level of sugar & typically when you eat sugar, this goes up. when your body has low blood sugar it regulates.

Diabetes has high sugar -> prolonged diabetes have lots of complications

Diabetes complications

effects on heart, kidneys, nerves, eyes (Blindness)

What is alcohol made of?

sugar, carbs

Why is it important to control stress?

Causes hormone release which affects metabolism. Shifts body from burning fat to burning something else. Hormonal negative effect can lead to CVD

High energy density

foods with a high number of calories for their weight

Low energy density

foods low in kcal but weigh a lot. Ex: bags of cut and peeled carrots

What does it mean for a nutrient to be essential?

In the sense that we need to consume it to survive, to function. Anything your body cannot produce, you must consume it in your diet

What happens if we are not getting enough carbs?

Liver gives us ability to convert molecules to carbs

Where do we get carbs from?

Plant source & animal source.

Animal source - dairy/animal milk. Meat does not have carbs in it. Eggs have v miniscule amount

-Majority of carbs come from plant sources (photosynthesis produces glucose)

Where do we store carbs?

Liver, muscles, adipose tissue

Liver as carb storage

stores carbs for whole body. Anatomical. Excess goes to muscles (if physically active)

What does it mean for a structure to be anatomical?

limited size therefore limited capacity

Muscles as carb storage

use a lot of energy. amount they take is exclusive for them. Muscle capacity changes depending on your state (exercise vs no exercise). Excess goes to fat cells

Adipose Tissue

fat cells. These tissues = not anatomical. No limit. The more you give them, the more they take

Problems of carbs and adipose tissue

1. The more you give fat cells, the more they take.

2. Once carbs get into adipose tissue, good luck getting it out. Hard to get rid of.

Types of carbs

monosaccharides, disaccharides, polysaccharides

Monosaccharides

1 molecule. 3 forms exist in nature: glucose, fructose, galactose

glucose

universal monosaccharide. most common. almost everything we consume has some glucose in it

fructose

very unique property - sugar is sweet, but fructose is the sweetest form. more profitable for food companies to use this bc less amount needed to make more sweet

galactose

rarest monosaccharide. don't get this in typical food

Disaccharides

2 molecules. 3 types: sucrose, lactose, maltose

sucrose

2 monosaccharides: glucose and fructose.

Most fruits, table sugar

lactose

glucose and galactose. all dairy products

maltose

least common. glucose & glucose.

wheat, fruit.

Polysaccharides

many glucose molecules. Ex: starch, fiber, glycogen

Starch

corn, rice, etc. 100% digestible

Fiber

Polysaccharide. Not fully digestible. healthy bc gives you false satiety. makes your digestive system busy. poorly digestible.

2 types: insoluble & soluble

glycogen

many glucose molecules that we store in our body. not a dietary source

Once carb is inside your body, no matter what you consume, the only 2 forms of carbs that exist (get converted to) ____. We do 2 things with it:

glucose; either use it to make ATP or if it is excess we store it and convert to glycogen

Sugar alcohols

less sweet and fewer cals vs glucose. naturally found in plants. used to make artificial sweeteners.

most common sugar alcohols

glycerol, sorbitol, mannitol, xylitol. Rate of absorption is low, causing a small rise in glucose and insulin

glycerol

4cal/g

xylitol

2.4 cals/g. used mostly in sugar gum.

sorbitol

2.6cal/g

mannitol

1.6cal/g

erythritol

absorbed and then excreted (body is equipped to handle a small amount)

Insoluble fiber

beneficial for digestive system. slows down absorption.