Chapter 4; Carbohydrates Flashcards
[..] [..] hype can be traced to the mid-200s, when nutrition guidelines started recommending that consumers eat more [..] [..]
whole grain x2
resulted in;
the food industry responded with an explosion of products marketed as containing whole grains
Rebecca Mozaffarian and her colleagues at the Harvard School of Public Health, the number of new products advertising their “whole grain” status was nearly [..] times higher than the number in 200. but many of these products contain a mixture of [..] grains, [..] grains, and a great deal of added [..]
20
whole, refined, sugars
grains include [..], [..], [..], [..], and other cereal [..] that humans use to make everything from granola bars, breads and breakfast cereals to pasta, crackers, and cupcakes
wheat, barely, rice, corn, grasses
nutrition scientists generally agree that eating “whole” grains is better for out health than eating “[..]” or “[..]” grains
refined
enriched
in a whole grain, all of the edible parts of the [..] plant seed (grains are [..]) are found in the food product, including the energy rich [..], the oil rich [..], and the fiber rich [..] coating
original , seeds
endosperm, germ, bran
whole grains contain the endosperm, germ, and bran in original proportions, and are a better source of [..] and [..]
fiber and nutrients
refined grains are stripped of the germ and bran, leaving only the [..] (starchy)
endosperm
enriched grains are refined grains, some of the nutrients are lost in processing are added back in [..]-vitamins, [..]
B vitamins, iron
carbohydrates provide fiber which is essential for […] (gut) and […] health. adds sweetness and flavor to food
intestinal
cardiovascular
the 2020 dietary guidelines for Americans suggests to consume at least half of all grains as [..] grains, increase whole grain intake by replacing [..] grains with [..] grains and for added sugars to consume less than [..]% of total calories from added sugars
whole, refined, whole, 10
the health and medicine division recommendations (DRIs);
total carbohydrates;
RDA: [..] g/day, AMDR [..]-[..]% of total calories
fiber;
AI: [..] g per [..] kcal/day
added sugars;
-< [..]% of total calories consumed
130, 45-65%
14 g per 1,000
25%
according to health and Medicine division recommendations (DRIs);
age 19-50; women [..] and men [..] g/day
age <-; women [..] and men [..] g/day
age 19-50;
women: 25 g/day
men: 38 g/day
age <- 51:
women: 21 g/day
men; 30 g/day
the World Health Organization (2003) says to consume <- [..]% of energy intake for added sugars
10
American heart association (2009); added sugars
women <- [..] kcal/day ([..] g)
men -< [..] kcal/day ([..] g)
100 kcal/day (25g)
150 kcal/day (38g)
refined grains are stripped of their [..] and the [..], leaving only the [..].
bran, germ, endosperm
- because many of the beneficial nutrients and phytochemical are found in the bran and germ, refined grains are considered to be much less healthful
enriched grains have some [..] and […] added back in, but nutritionally they still pale in comparison with [..] grains
vitamins and minerals
whole
consuming whole grains has been linked to a host of health benefits;
reduced risk of [..] disease, [..], […] - even certain types of […]. the Dietary Guidelines for Americans advise that they should consume at least [..] of their grains as whole grains
heart disease, obesity, diabetes
cancer
half
whole grains are a primary source of the macronutrient […]
carbohydrate
carbohydrates are molecules made up of carbon, hydrogen, and oxygen arranged as one or more [..] units. they are abundant in [..] and other [..] foods, as well as in [.] and some [..] products, and are key sources of fuel for the body, providing [..] kcal of energy per gram
sugar, grains, plant. milk x2, 4
carbohydrates are the dominant source of energy for vigorously […] muscles; they are the exclusive source of energy for [..] blood cells and provide the vast majority of energy needed by the [..] under normal circumstances.
exercising
red
brain
consuming adequate carbohydrate in our daily diet also reduces the use of amino acids to [..] glucose, thereby sparing [..] from being broken down for this purpose
synthesize
proteins
carbohydrates function in the body is being a source of [..] for all cells in the body, indispensable source of energy for the [..], [..] blood cells, and muscles during intense [..], important for [..] health, reduces the use of [..] for energy
energy, brain, red
exercise, intestinal, protein
carbohydrates function in food is being a source of [..] and adding [..] and [..]
fiber
sweetness and flavor
fruits, vegetables, grains, and milk and milk products are sources of carbohydrates
yes
the health and medicine division of the national academy of sciences recommends that adults consume [..]-[…]% of their daily calories from carbohydrates
45-65
the three most abundant monosaccharides are [..], […], and [..]
fructose,
glucose, and galactose
fructose, is the sweetest of these sugars, is found [..], some […] and […] also used along with [..] to sweeten foods and beverages by food manufacturers who process corn to create high fructose corn syrup
fruit, some vegetables, and honey
glucose
glucose is the most [..] sugar in our diet because it is part of all disaccharides, starches, and many fibers
abundant
galactose is one of the two […] (the other is glucose) that make up disaccharide found in [..]
monosaccharides
milk
the disaccharides are made up of pairs of monosaccharides and are called […], […], and […]. the mammary glands of humans and other mammals synthesize .., which is incorporated into milk to feed offspring
lactose, maltose, and sucrose
lactose
maltose is composed of two glucose molecules and is produced when […] is broken down in digestion
starch
sucrose, or “table [..]”, is a disaccharide composed of glucose and fructose. we must digest disaccharides into their component monosaccharides before they can be [..] by cells of the intestines
sugar
absorbed
humans and other animals break down som complex carbohydrates into [..] monosaccharides during the process of digestion. these molecules are [..] by the cells of the intestine and dumped into the […] for all body cells to pick up and use for […]
individual
absorbed, blood, energy
oligosaccharides contain […]-[…] linked monosaccharides, where’s polysaccharides are chains (or polymers) of more than [..] monosaccharides
3-10
10
most complex carbohydrates in our diet come from […]. polysaccharides in plants may function as a source of stored […] (starch) or as a […] material (fiber)
plants
energy
structural
starches are polysaccharides that serve as stored […] for the plant and include amylose and amylopectin, which are found in grains, legumes, and starchy vegetables such as peas, potatoes and corn
energy
fibers include polysaccharides cellulose and hemicellulose which make up plant cell walls and impart structure to the plant. fiber rich foods are numerous and include whole grains and vegetables such as winter squash and beans and fruits such as raspberries and pears
yes
humans lack the digestive enzymes to break down plant […] so it passes [..] through the digestive tract
fiber
undigested
carbohydrates are found in all [..] foods and some [..] foods
plants, animals
e.g.
- grains, vegetables, fruits, lentils, beans, nuts (starches, whole grains, cereals, sugars)
- milk and dairy products, honey
carbohydrate synthesis in plants;
1. photosynthesis captures [..] energy to convert [..] [..] and [..] into a three carbon sugar from which fructose and glucose can be synthesized
2. plants can stores this glucose as [..], which is an important source of energy for us
light, carbon dioxide and water
starch
humans and other animals also store [..] for later use. the storage form of carbohydrates in animals is called [..]. glycogen is made and stored primarily In the [..] and [..]
glucose
glycogen
liver and muscles
when glucose is needed to maintain proper blood sugar levels, the [..] breaks down the glycogen into [..] and releases it into the [..]. glycogen in skeletal muscles is broken down to supply fuel for [..] muscles during intense exercise
liver
glucose
blood
contracting
basically monosaccharide;
glucose; circulates in the bloodstream,. fruits, vegetables, and honey
fructose; found in fruits, vegetables, and honey
galactose; make up milk sugar
disaccaride;
maltose; large amounts as a product of starch digestion, very little is found in the foods we eat
sucrose; table sugar. found in fruits and vegetables
lactose; milk sugar, found only in milk, yogurt, and other dairy products
the energy found in carbohydrates comes, ultimately, from the [..]
sun
photosynthesis enables plants to capture the energy of […] and convert it into [..] energy in the form of glucose and fructose. plants then link glucose molecules together to form [..] and some dietary [..]
sunlight, chemical, starch, fibers
in grains, most of the starch is contained in the [..], which, if the seed is planted, will provide energy to the growing plant embryo, or [..]. the energy is not readily [..] to humans when they consume the grain [..], however, because the endosperm is surrounded by the non digestible fiber [..] coating. hence, humans have crushed, pulverized, or modified whole grains to expose the inner endosperm. without such modifications , many grains would be unpleasant to eat or would pass largely [..] through the digestive tract
endosperm, germ
accessible, whole
bran
modified, undigested
beginning in the 19th century, “[..]” grains became common practice
refining
sophisticated milling machines allowed humans to operate the starchy endosperm from the touch brain and oily germ. the purified endosperm could then be ground into white flour.
refining grains served two purposes;
1. it helped keep flour from [..] - because if not removed, the oily germ would quickly turn rancid when exposed to air and 2. it provided a desirable [..] - in white bread, a soft and smooth texture
spoiling
consistency
- endosperm contains the highest amount of [..] and […] and is all that remains when grain is refined
- bran contains the majority of dietary [..] and a significant amount of [..] vitamins and [..]
- Germ, the embryo of the seed that germinates and grows and contains essential fatty acids and number of B vitamins and mineral
starch, protein
fiber, B, minerals
side note; the vast majority of vitamins, minerals, and phytochemical are found in the germ and bran of whole grains
the whole grain stamp is found in front of package icon that tells consumers that a product contains at least [..] grams of a whole grains per serving
8
50%+ contains minimum 8g
100% all of its grain ingredients a re whole grains 16g
the American heart association said to look for products with a total carbohydrate to fiber ration of less [..]:[..] - the approximate ratio of carbs and fiber in whole wheat flour. most white all purpose flour has a ratio of over 20:1. the carb to fiber ratio is intended to help consumers identify healthier whole grain food
10:1
Dietary guidelines for American nutrition guidelines recommend looking for whole grains as the [..] ingredient in food products, smaller portions on plate [..]
first
1/4
- Begins in the mouth
– Mechanical digestion:
chewing
– Chemical digestion: Salivary
amylase breaks starch into
shorter links - Carb digestion pauses in
stomach - Carb digestion resumes in
small intestine
– Pancreatic amylase
– Enzymes within the microvilli
(brush border) complete
digestion of starch into
monosaccharides - Absorbed into bloodstream
- Undigested fiber and resistant
starch move to large intestine
– Fuel gut bacteria
– Fiber = happy gut
yes
only monosaccharides, such as glucose, can be absorbed but he cells of the small [..]
intestine
- pancreatic amylase breaks oligosaccharides into [..] + [..]
- maltose breaks maltose into [..] + [..]
- sucrase breaks sucrose into [..] + [..]
- lactase breaks lactose into [..] + [..]
- maltose + glucose
- glucose + glucose
- glucose + fructose
- glucose + galactose
monosaccharides are absorbed by the [..] intestine, then transported to the [..], glucose used immediately for [..], fructose and galactose must go to [..] first and be converted to glucose
small. energy, liver
insulin is a [..] secreted by [..] in response the elevated blood glucose. it removes glucose from the blood to be be used by cells in [..] muscle, [..] muscle and [..] tissue. it acts as an [..] hormone that stimulates glycogen storage in liver and skeletal muscles and enables conversion of glucose to fat in the liver and adipose tissue
hormone, pancreas
skeletal, cardiac, fat
anabolic
the body uses specific [..] to break down carbohydrates. in the mouth, the enzyme salivary amylase breaks down [..] molecules into shorter [..]. in the small intestine, the enzyme pancreatic amylase digests starch into oligosaccharides and maltose. oligosaccharides are broken down into glucose and maltose by enzymes present on the surface of the [..] in the small intestine
enzymes
starch to polysaccharides
microvilli
then;
maltase is the enzyme that breaks down maltose into two glucose units, sucrase digests sucrose into fructose and glucose, and lactase breaks down lactose into glucose and galactose. these monosaccharides are then absorbed by the cells lining the small intestine and from there travel into the blood for distribution throughout the body
lactose intolerance, is the result of producing low levels of [..] in the intestines
lactase
in most people, lactase levels [increase or decrease] with age
decrease
treatment for lactose intolerance is to cut back on [..] products. there are many lactose free dairy alternatives on the market, as well as milk products such as Lactaid that incorporate the enzyme lactase to improve […]
dairy
digestibility
fructose and galactose are taken up from the blood primary by the […], where they can be converted into [..]. they then may be exported back into the blood for [..] to cells throughout the body
liver
glucose
distribution
after we eat, levels of glucose in our blood [..] this stimulates the pancreas to secrete the crucial hormone [..] which directly stimulates the cells in [..] muscle, [..] muscle, and adipose tissue (but not other tissues) to take up glucose from the [..]. because more glucose may be available than is needed, the body is able to store the [..] energy for later use
rise
insulin
skeletal, cardiac
blood, excess
insulin is a potent [..] hormone in that it stimulates the [..] of a larger molecule from smaller ones, enabling the [..] and [..] muscles to use this [..] glucose to synthesize and store it as the polysaccharide glycogen.
anabolic, synthesis
liver and skeletal
excess
because there is a [..] to how much glycogen can be [..], insulin also promotes the [..] of glucose to fat in the liver and adipose tissue
limit, stored
conversion
hours after you’ve eaten and the levels of glucose in the blood have fallen, the pancreas releases another hormone, [..], which signals [..] cells to release glucose into the blood to maintain blood glucose levels. the liver produces and exports this glucose by breaking down [..], as well as by synthesizing new glucose molecules (primarily from amino acids)
glucagon, liver
glycogen
different foods have different effects on blood glucose, even when they contain the same amount of starch and sugars. specifically, how the body [..] particular carbohydrates dictates how [..] and what [..] glucose will released into the bloodstream and therefore how much [..] is released
processes
much, rate
insulin
liver glycogen is broken down to maintain [..] levels. liver storage ~ [..] g glycogen
muscle glycogen : broken down to provide [..] to do work. skeletal muscle storage ~ [..] g
blood, 100
energy , 500
starches that remain undigested and enter the large intestine are called [..] starches. diets high in […] starches may improve our responsiveness to […] and make people feel full for longer periods
resistant x2
insulin
e.g. beans , underripe bananas, whole grain kernels, and pasta
starches in some foods are digested so quickly that blood glucose [rises or falls] nearly as rapidly as what is seen after an equal amount of pure glucose consumed
rises
e..g boiled potatoes and many breakfast cereals
sucrose, lactose, and fructose and foods that contain these sugars (such as candies, dairy foods, and fruit) often produce a [more or less] dramatic rise in blood glucose than do starchy foods. this is because fructose and galactose have no immediate impact on blood glucose levels until they are converted to glucose in the liver
less
starchy
sugars in the form of syrups and other caloric sweeteners are often added to food products to enhance [..]. these added sugars also have functional roles in [..] foods, [..] baked items, and improving [..] and [..]
palatability.
preserving, browning, texture and appearance
side note; on food labels are listed by a wide variety of names such as brown sugar, corn sweetener, dextrose, fructose, fruit juice concentrate, glucose, honey, invert sugar, lactose, maltose, molasses, raw sugar, sucrose, and table sugar
a common and controversial added sugar is high fructose corn syrup (HFCS)
yes
the best approach is to […] intake of all added sugars, including HFCS. added sugars do not include [..] occurring sugars such as those found in fruit or milk
minimize
naturally
most Americans consume too much added sugar, eating on average about […] calories per day, or [..]% of total calories
270
13
two main issues are associated with excessive consumption of foods with added sugars, the addition of sugars to foods adds substantial calories without adding significant bulk; this increases the energy density of foods and is likely on contributing factor to the increased prevalence of obesity around the world.
added sugars also provide no additional vitamins or minerals and therefore decrease the nutrient density of foods.
the dietary guidelines for Americans recommend consuming less than [..]% of total calories from added sugars
10
eating too much added sugar promotes cavities, also known as dental […]
caries
individuals are especially at risk of cavities if they frequently expose their teeth to [..] by eating sweet snacks and sticky foods, sucking hard candy, or by slowly sipping sugary drinks. the more our teeth are exposed to sugar, the more the bacteria on our teeth metabolize the sugars and produce acids that [..] tooth enamel and decay teeth. and cavities are not just in childhood - [..]% of people have had cavities that developed at 18 years and older
sugar
dissolve
85
because excess sugar consumption is also associated with chronic disease such as […] and […] disease, the food industry has created a handful of sugar alternatives that are regulated by the U.S. Food and Drug administration (FDA), which has deemed them Generally Recognized as Safe (GRAS) for use in foods.
obesity
cardiovascular
there are two main types of safe sugar alternatives;
1. those that are a source of [..], the [..] sweeteners, and
2. those that are not called the [..] sweeteners
calories
nutritive
nonnutritive
nutritive sweetness include the polyols, which are [..] forms of sugars. [..] (the alcohol form of glucose) and [..] (the alcohol form of mannose) are made from naturally occurring sugars in plants, and because they are poorly absorbed by the body, they provide fewer than [..] kcal per gram. because of their poor [..], excessive consumption of sugar alcohols often causes [..] symptoms including diarrhea
alcohol, sorbitol, mannitol
4, absorption
gastrointestinal
nonnutritive sweeteners include the widely used [..] products (such as Nutrasweet and Equal). aspartame is made by linking two amino acids and like protein, it provides [..] kcal per gram. it is intensely sweet (about [..] times sweeter than sucrose) that very little is used to achieve the same level of sweetness as sucrose; consequently, aspartame does not significantly [increase or decrease] the amount of calories in a food.
aspartame, 4
200, increase
another popular nonnutritive sweetener is [..] extract (trivia), made from the sweet [..] of subtropical stevia plants. e.g. of other nonnutritive sweeteners found in foods and in the “sugar” bowl at your restaurant table include Sucralose (Splenda) and saccharin (Sweet’N Low)
stevia
leaves
scientists in both Europe and North America have concluded that aspartame is safe in amounts that are [..] consumed and that there is little health risk for […] use in healthy individuals
commonly
moderate
have studies show that healthy weight individuals or obese individuals consume more diet beverages.
obese individuals
however, these studies do not demonstrate that diet drink consumption actually causes obesity. (might compensate by eating more calories from solid foods and snacks)
a recent study found that consumption of diet beverages in obese subjects was associated with decreased [..] and cease emerge intake from [..], refined [..], and added [..]
physical
fat, carbohydrates, sugars
the consumption of sugar sweetened beverages is more strongly linked to increased risk of both diabetes and heart disease than is the consumption of diet beverages
yes
the wises approach would be to drink sugar sweetened beverages […], drink diet beverages only [..]. and [..] these drinks with water and unsweetened tea and coffee
rarely
occasionally
replace
many of the benefits of eating whole grain foods likely come from the [..] in them
fiber
the health and medicine division (HMD), the health arm of the US National Academy of Sciences, recommends that men younger than 50 years consume [..] grams of fiber per day and women younger than 50 years consume [..] grams of fiber a day. only about [..]% of Americans meet these goals consuming an average of 17 grams of fiber a day
38
25
5
the average US intake of fiver is [..] grams/day
17
anatomy of a whole grain
outside layer; bran
middle layer; endosperm
small circle inside; germ
fiber includes cellulose and other non starch polysaccharides and oligosaccharides that cannot be broken down by human digestive [..]. fiber is typically found in and around [..] cell walls.
enzymes
plant
e.g. in legumes, nuts and seeds, berries, many vegetables, fruit covering, such as apple peels, and the brain surrounding grains, such as wheat, oats, rice, and rye
there are several ways to categorize fiber. one way is by the […] of the fiber in water. soluble fiber [..] in water, often forming vicious gels, and it is typically readily [..] (broken down) by bacteria in the colon. in contrast, […] fiber does not dissolve in water and is typically poor fermented. it passes through the [..] tract relatively intact
solubility, dissolves, fermented
insoluble , gastrointestinal
dietary fiber is […] carbohydrates that are present [..] in intact plant foods
undigestible
naturally
functional fiber is […] carbohydrates that have been […] to a food product and have health benefits that are similar to those of dietary fiber. e.g. psyllium seek husks and pectin isolated from fruits
non digestible
added
when you add up a food’s dietary fiber and its functional fiber, you get its [..] fiber
total
subtract fiber (dietary fiber e.g.) from total carbohydrates to determine the amount of carbohydrates that can be [..] and [..]
digested
absorbed
the FDA recently implemented new regulations that limit the listing of fiber on food labels to only those that meet its new definition of dietary fiber. this definition states that dietary fiber is fibers that are naturally part of the intact food and certain added synthetic or isolated fibers that [..] human health
naturally
benefit
added fibers on food must demonstrate to have at least [..] beneficial effect, such as lowering blood cholesterol or improving bowel function
one
the daily reference value (DRV) for dietary fiber on food labels was increased from [..] grams to [..] grams
25
28
fiber (particularly [..] fiber) is healthful in part because it softens [..] and thereby maintain regular [..] movements and reduced the risk of hemorrhoids and diverticular disease. insoluble fiber has also been shown to [..] the risk of diabetes
insoluble
stools, bowel
decrease
the higher intake of […] fiber has been shown to reduce the risk of coronary heart disease. diets high in soluble fiber also [..] the emptying of food from the stomach into the small intestines which may extend the sensation of [..] following a meal. many soluble fibers also slow digestion and absorption and reduce the rise in blood glucose following a carbohydrate containing meal, which may improve blood [..] control in those with diabetes. another bonus is that a high intake of foods rich in both insoluble and soluble fibers may reduce risk of some types of cancer. in addition nutrition surveys demonstrate that high fiber diets are more likely to be nutrient dense and Lower in saturated fats, sodium and added sugar
soluble, slow, fullness, glucose
in addition to encouraging consumption of carbohydrate rich plant foods, the Dietary Guidelines for Americans recommend that people consume at least […] of all grains as […] grains and increase whole grain intake by replacing […] grains with […] grains
half, whole, refined, whole
the HMD recommends that people consume carbohydrates within a certain range, the acceptable macronutrient distribution range, the acceptable macronutrient distribution range (AMDR) of [..]-[..]% of total calories, which is associated with a reduced risk of chronic disease while providing adequate amounts of essential nutrients
45-65%
the RDA calls for [..] g/day of total carbohydrates
130
the major source of added sugars in the American diet is [..]
beverages
