Chapter 1 - Food for Health - Flashcards
Nutrition
Science of interaxns btwn living organisms and food
Nutrients
Chemical substances in foods that provide energy, form structures in the body (e.g. hair), and help regulate body processes
What is the problem w/ processed foods and fast foods, relative to whole foods?
Processed and fast foods tend to have more kcalories and less vitamins, minerals, and antioxidants than do fresh whole foods.
> Processed = nutrients removed, sometimes replaced
convenience makes it easier for people to overeat
How Healthy is the Typical American Diet?
The typical North American eats too many high-kcalorie, low-nutrient foods
» foods low in vitamins, minerals, and phytonutrients.
Essential nutrients
must be provided in diet bc we don’t make it (you have to eat it)
> either cannot be made by the body or cannot be made in large enough quantities to meet needs
How has diet affected health in North America?
> Incidence of Type II (adult-onset) diabetes is skyrocketing
Heart disease is #1 reason ppl die in the US
Lifestyle and diet interacts w/ genes
Fortified foods
nutrients added artificially, don’t occur naturally in the food
Enriched foods
nutrients are replaced in the food - do occur naturally
E.g. grains - B vitamins and iron added to flour
What are Energy-yielding Macronutrients? What are the 3 types?
Energy-yielding nutrients (provide calories) needed in body in large amounts.
3 types:
>Carbs
>Proteins
>Fat
> Alcohol has calories but not nutritious so NOT a macro
What is the purpose of energy-yielding macronutrients?
To provide energy to body, measured in kilocalories (or kilojoules)
kilocalorie (kcalorie, kcal)
The unit of heat that is used to express the amount of energy provided by foods.
[aside]
>It is the amount of heat required to raise the temperature of 1 kilogram of water 1 degree Celsius (1 kcalorie = 4.18 kjoules).
Phytochemicals (phytonutrients)
decrease risk factors of chronic diseases but are non-essential
Where are phytonutrients found?
Found naturally in all plant products
> Protects the plant, so highest in concentration outside of plant
What are the 3 types of carbs?
- Sugars
- Starches - larger
- Fiber - we can’t digest it
How many calories in carbs?
4 kilocalories/gram
What are 4 food sources of carbs?
Vegetables, fruits, starch, dairy
How does size of carb relate to sweetness?
Smaller units of carbs = more sweetness
> Ripe fruit and unripe veggies have small units
How do we digest fiber?
We don’t. Bacteria digest it; thus we don’t get any energy from fiber.
energy-yielding nutrient
A nutrient that can be metabolized to provide energy in the body.
macronutrient
A nutrient needed by the body in large amounts. These include WATER and the energy-yielding nutrients: carbohydrates, lipids, and proteins.
micronutrient
A nutrient needed by the body in small amounts for proper fxning, provide no energy. These include vitamins and minerals.
Organic molecule
A molecule that contains carbon bonded to hydrogen.
inorganic molecule
A molecule that contains no carbon-hydrogen bonds
Carbohydrates
organic,
energy-yielding (4kcals/gram),
water-soluble;
include starches, sugars, fibers and glycogen
Lipids
organic,
energy-yielding (9 kcalories/gram),
not water-soluble;
include fatty acids, triglycerides, and cholesterol
Proteins
organic,
energy-yielding (4kcalories/gram),
water-soluble;
are made of amino acids
Malnutrition
Any condition resulting from an energy or nutrient intake either above or below that which is optimal.
Undernutrition
a form of malnutrition caused by a deficiency of energy, nutrients or both
Overnutrition
an excess of energy or nutrients.
> Overnutrition of energy can lead to overweight, obesity and a variety of chronic illness such as diabetes;
> overnutrition of vitamins and minerals can lead to organ damage, death, etc.
What determines food choices?
> Availability
Cultural and family background; >prior experience;
Social acceptability;
Personal preference; >Psychological and emotional state;
Health concerns
How to choose a healthy diet
> Eat a variety of nutrient-dense foods
Balance energy in with energy out to avoid overweight
Eat everything in moderation; be aware of portion sizes
What kind of lipid provides energy and how much?
Triglycerides, 9cals/gram
What are 2 names lipids are called and what’s the diff?
Fats = solid Oils = liquid
What do ppl think foods high in fat are fattening?
Bc fats are highest in cals (at 9cals/gram) vs other macromolecules
Two types of fatty acids, major difference
Saturated - solid at room temp
Unsaturated - liquid at room temp
What are food sources of fat?
oils, spreads, animal food
What are proteins and what are they used for?
> Combinations of amino acids
Required for growth, maintenance, and repair of the body
If needed, can supply energy
How much energy do proteins provide?
4 kilocals/gram
Why don’t we usually use it for energy or store it?
Body doesn’t want to use it for energy (we don’t store) bc it has too many important fxns
Food sources of protien
meat, fish, poultry, dairy, legumes, grains/starch, veggies
What we eat is mainly driven by what 3 factors?
Taste, cost, convenience
> TASTE is extremely important
Nutrient Density
A measure of nutrients in a food compared to its energy
Does the body absorb nutrients from different foods the same?
Nope! The same nutrient from one food is not absorbed the same way as the same nutrient from another food
What happens if there’s too much restriction in the diet?
Leads to overeating unhealthy foods
Observational studies
look at health and disease patterns overtime, can’t see cause/effect
Clinical trials
intervention = experiment
The researcher is doing something, not just observing
