Nutrition Chapter 4: Carbohydrates
lactose
"milk sugar" found in dairy products
sucrose
"table sugar" most abundant disaccharide found naturally in sugar cane and sugar beets
after carbs are digested into monosaccharides, then what?
-absorbed through the intestinal cell mucosa -transported to liver via h. portal vein -depends on metabolic needs
glycocemia
-blood glucose level < 70 mg/dl -occurs with excess insulin production -signs: hunger, dizziness, feeling light-headed, confused, weak, or beginning to sweat -symptoms: Eat or drinking carbohydrate-rich foods • Eating smaller, well-balanced meals throughout the day
epinephrine and norepinephrine
-both raise blood glucose -stimulates gluconeogenesis and glycolysis -released from the adrenal glands
benefits of low-fat and fat-free dairy products
-contain 1 to 17 grams of lactose
4 other hormones that help regulate blood glucose
-epinephrine -norepinephrine -cortisol -growth hormone
Three nutritionally important monosaccharides
-glucose -fructose -galactose
prediabetes
-impaired glucose tolerance • Fasting blood sugar between 100 mg/dl and 126 mg/dl • High risk of developing diabetes and heart disease
insulin
-lowers blood glucose levels -essential for glucose to enter the bloodstream liver, kidneys and brain cells do not need insulin to use glucose -stimulates glycogenesis and lipogenesis, inhibits lipolysis
best carb choices
-nutrient dense -low in saturated fat -high in fiber -higher amounts complex carb
type 2 diabetes
-produces insulin but have become insulin resistant due to increase adipose cells -90-95% of diabetics -pancreas overproduces insulin and eventually decreases production due to overuse -damages vital organs -screening: once/3 years after age 45; overweight kids 10 years and on
four functions of carbohydrates in the body
-provides energy -maintains blood glucose level (cannot use muscle glycogen): glycogenolysis occurs 4 hours after a meal -spare protein -prevents ketosis
examples of artificial sweeteners
-saccharine (sweet-n-low) -aspartame (equal, nutrisweet) made from 2 amino acids PHENYLALANINE + ASPARTIC ACID -acesulfame (sweet one) -sucralose (splenda) stable under heat, good for cooking -neotame -advantame: processed foods -truvia: 3 carbs from sugar alcohol
gluten
-the protein part of wheat, rye and barley -recommended for treatment of celiac disease -
glycogen
-the stored form of glucose in animals
what to focus on when consuming fruits and vegetables
100% fruit juice, whole fruits and vegetables
functional fiber
ADDED TO FOODS. EX.)CELLULOSE, PSYLLIUM,GUAR GUM, PECTIN
Type 1 diabetes
Autoimmune disease where the immune system destroys beta cells of the pancreas. No insulin is being produced. -begins in early childhood -5-10% of diabetics -requires daily insulin injections and blood glucose monitoring
How are carbs produced?
By plants during photosynthesis
resistant starch
TYPE OF FIBER FERMENTED IN INTESTINE, FORMS BUTYRATE( FATTY ACID THAT MAY REDUCE CANCER RISK).Also acts as prebiotic. Found in oats, asparagus,bananas
what makes up the foundation of diets around the world?
carbohydrate-rich plant foods
constipation
caused by sluggish muscle contractions in the colon that move the stool too slowly leading to excessive water absorption • Causes formation of hard, dry stool that are painful to expel • Treatment: consume insoluble and soluble fiber
growth hormone
conserves blood glucose -stimulates fat breakdown for energy -reduces uptake of glucose by muscle cells -increases glucose production in the liver
dietary recommendation for lactose maldigestion
continue to consume common dairy products
what is lactose intolerance?
deficiency of lactase, the enzyme that digests lactose
monosaccharides + glucose =
disaccharides
how are carbs digested and absorbed?
disaccharides and starches are broken down to monosaccharides, then the monosaccharides are absorbed by the small intestine -fiber is not digested in the GI tract
added sugars
empty calories sugars added to processed foods and sweets
glucose is used as
energy converted to glycogen through glycogenesis to be stored
how does fiber reduce blood cholesterol levels
fiber in the small intestine binds with bile that is made of cholesterol, preventing it from reentering into the liver. it turns to feces
benefits of the flesh and skin of fruits and the benefits of vegetables
flesh of fruits: contains simple sugars (monosaccharides and disaccharides) and pectin skin of fruits: contains cellulose vegetables: starch and fiber
the most abundant carbohydrate
glucose
fiber cautions
should be introduced into a diet slowly and high fiber can cause flatulence and bloat -may reduce the absorption of minerals such as iron and zinc if the diet is low in these minerals.
how are ogliosaccharides and monosaccharides similar?
similar in length
what type of carbs do fruits and vegetables offer?
simple sugars, fiber and sugar
#1 source of added sugars in the US
soda, energy drinks and sports drinks. Uses high fructose corn syrup
two types of fiber
soluble and insoluble
waht kind of food is most likely to cause dental cavities?
sticky foods like hard candy or dried fruits
glyogen
storage form for humans
starch
storage form for plants
amylose
straight chain of polysaccharides found in starch; makes up 40% of starch
fiber
structural form, not digested
fructose + glucose =
sucrose
3 disaccharides
sucrose lactose maltose
sweeteners
sugar- naturally occuring carbs- increases blood sugar levels; HONEY, SYRUP, DEXTROSE, SUCROSE MALTOSE, AGAVE NECTAR,
what reduces dental caries?
sugarless chewing gums
simple carbs
sugars
fructose
sweetest of natural sugars found abundantly in fruit part of high fructose corn syrup
major differences between type 1 and type 2 diabetes
type 1: under age 30, lack of insulin produced by pancreas, requires external insulin, IDDM, child onset, brittle type 2: above age 40, insulin resistant, case by case, NIDDM, adult onset
condensation
when two monosaccharides join together to form a disaccharide
what is the best source of carbs?
whole foods (grains, vegetables, fruits, beans)
can packaged foods be a good source of carbohydrate? if yes, are there precautions?
yes; yes, good sources of starches but can also contain high amounts of added sugars, fat, sodium, and kilocalories • Consume in moderation.
Acesulfame-K
• About 200 times sweeter than sucrose • Used as a tabletop sweetener and in chewing gum, candy, desserts, yogurt, and alcoholic beverages • The body does not metabolize acesulfame-K and it's excreted intact in the urine.
how does fiber help prevent cancer?
• Decreases the amount of time cancer- promoting substances spend in contact with the intestinal lining • Encourages the growth of colon-friendly bacteria and their fermentation by-products • Reduces concentration of bile acids in the colon
gestational diabetes
• Diagnosed when a woman develops it during pregnancy with no previous diagnosis of diabetes. • The cause is the ineffectiveness of insulin, most likely due to the influence of pregnancy-related hormones. • Uncontrolled glucose can cause a larger newborn baby and complications during pregnancy.
soluble fiber
• Dissolves in water • Easily fermented by bacteria in the intestine • Examples: Pectins, mucilages, beta-glucans • Health benefits: Lowers cholesterol, Lowers blood glucose, Appetite control
insoluble fiber
• Does not dissolve in water • Not easily fermented by bacteria in the intestine • Examples: Cellulose, lignins, some hemicelluloses • Health benefits: Increases stool bulk, Relieves constipation
why is physical activity important for diabetics?
• Increases insulin sensitivity • Reduces body fat • Lowers blood pressure and lipids
how do soluble and insoluble fiber help digestion
• Insoluble fiber helps reduce transit time of foods in the colon. • Soluble fiber helps make stool easier to pass by increasing bulk and softening texture.
characteristics of foods with added sugars
• Keep products moist • Provide brown color to pastries and baked goods • Function as preservatives and thickeners • Works with yeast to make bread rise • Make foods taste sweet
Sucralose
• Known as Splenda and can be used in baking • Developed by slightly changing the structure of the sucrose molecule • It isn't digested or absorbed by the body—it passes through the GI tract and is excreted.
long-term damage from diabetes
• Nerve damage • Leg and foot amputations • Eye diseases • Blindness • Tooth loss • Gum problems • Kidney disease • Heart disease
aspartame
• One of the most-used sugar substitutes in the world • Composed of two amino acids • Modified aspartic acid and phenylalanine • Provides 4 kilocalories per gram • 200x sweeter than sucrose • Individuals with phenylketonuria (PKU) are unable to metabolize phenylalanine and must avoid ingesting aspartame.
sugar alcohols
• Polyols are called sugar alcohols because they have the chemical structure of sugar, with an alcohol component added. • Are found in plants and produced synthetically • Used in chewing gums, candies, and baked goods • Cause diarrhea in excessive amounts
types of sugar substitutes
• Polyols • Saccharin • Aspartame • Acesulfame-K • Sucralose • Rebaudioside A • Neotame
the best way to reduce risk of diabetes is:
• Shed some excess weight • Exercise regularly • Eat a balanced, high-fiber, healthy diet -meeting with a health professional for support may also help
naturally occurring sugars
• Sugars such as fructose and lactose found naturally in foods • Tend to be nutrient dense • Found in fruit and dairy products
how do sugars and starches cause dental caries?
• They provide an energy source for the bacteria in the mouth. • As bacteria grow, the produce acids that erode the enamel of the teeth.
dietary recommendations for lactose intolerance
• Vary depending on the individual's threshold • Consume small amounts of dairy throughout the day. • Eat lactose-containing foods with a meal or snack. • Whole milk tends to be better tolerated than skim milk. • Cheese has less lactose than milk, especially hard, aged cheese such as Swiss, cheddar, blue, and parmesan. • Consume yogurt with live, active cultures. • Consume lactose-reduced products or take lactose pills or drops with foods.
how does fiber help prevent diabetes?
• Viscous soluble fiber helps slow digestion and absorption of glucose, helping control blood glucose levels. • Higher consumption of fibers from cereals has been shown to reduce the risk of developing diabetes.
lactose intolerance
When symptoms of lactose maldigestion result in nausea, cramps, bloating, flatulence, and diarrhea
Diabetes Mellitus
a medical condition in which an individual doesn't have enough insulin or is resistant to the effects of insulin, which results in a rise in blood glucose level
glycemic index (GI)
a rating scale of the likelihood of foods to increase the levels of blood glucose and insulin. CONCERN: does not account for carbohydrates
functional fiber
a type of fiber that has been extracted or isolated from a plant or manufactured by the food industry, and has been shown to have health benefits
which food product does not contain glycogen?
animal products
how is glucose stored?
as glycogen; which is more branched than amyloceptin
glucose
basic carbohydrate unit used by the body for energy -most abundant carb -preferred source of energy for the body
body's desired blood glucose level
between 70 md/dl and 110 mg/dl
how are oligosaccharides and polysaccharides similar?
both make up cellulose in plant cell walls and both escape digestion (like fiber)
amylopectin
branched chain of polysaccharides found in starch; makes up 60% of starch
how does liver glycogen respond to blood glucose levels?
low blood glucose -> breakdown of glucogen -> increase blood glucose
glucose + glucose =
maltose
polysaccharides
many units of glucose
monosaccharide
one unit of sugar
galactose
rarely found on its own commonly occurs as part of the disaccharide lactose
DRI recommendation for carbs
minimum of 130 grams/day (most adults consume more than this)
glucose
most abundant monosaccharide in the body main source of energy for brain and red blood cells
why can't humans digest fiber?
most fiber is in the form of cellulose; a straight chain of glucose units that are bound together by a beta glycosidic bond. Humans lack the enzyme that is needed to break this bond.
critical energy source for...
nerve cells, red blood cells and the brain
DRI fiber recommendation
14 grams per 1,000 kilocalories
what is the estimated medical cost for diabetes in the US annually?
170 billion
reduced calorie sweeteners
2 calories/g increase blood sugar levels slightly sugar alcohols: malitol, sorbitol, xylitol sugar free gum and mints
AI recommendation
25 to 38 grams per day
how many Americans does diabetes affect? Of these people, how many are not diagnosed?
28.5 million; 7 million
my plate recommendation for whole grains
3 servings per day
AMDR
45-65% of kilocalories
my plate recommendations
6 servings of grains 3 servings of vegetable 3 servings of dairy 2 servings of fruit
diverticulosis
Diverticulosis is a condition in which increased pressure in the colon causes weak spots along the wall, forming pouches called diverticula.
naturally gluten free products
FRUITS, VEGETABLES, NUTS, SEEDS, MEAT, EGGS, FISH, POULTRY
gluten containing ingredients
HVP( HYDROLYZED VEGETABLE PROTEIN), MALT, SOY SAUCE, FOOD STARC
nutrients of concern regarding lack of gluten
IRON, CALCIUM, B VITAMINS, VITAMIN D, FOLA
lactose maldigestion
Inability to digest lactose due to low levels of the enzyme
dietary fiber
NONDIGESTIBLE SUPPORT STRUCTURE OF PLANTS,SEEDS
symptoms of high blood glucose
Polyuria: excessive urination Polydipsia: uncontrollable thirst Polyphagia: strong desire to eat
saccharin
has been in use for over a century
glycemic load (GL)
he amount of carbohydrate in a food multiplied by the amount of the GI of that food -Adjusts the GI to account for the amount of carbohydrate typically eaten
benefits of dietary fiber
helps to lower the risk of: Bowel irregularity • Constipation and diverticulitis • Obesity • Heart disease • Cancer • Diabetes
cortisol
increases blood glucose -stimulates gluconeogenesis -reduces uptake of glucose by muscle cells
glucagon
increases blood glucose levels -stimulates the release of glucose in the blood -stimulates glycogenolysis -promotes conversion of lactic acid to glucose
how does fiber help prevent obesity?
increases satiety, resulting in reduced food intake
diverticulitis
infection of the diverticula
two hormones that regulate BGL (Blood Glucose Level)
insulin and glucagon
what happens to excess glucose?
it is stored as fatty acid and glycerol for storage in adipocytes (fat cells)
sugar substitutes add sweetness but not
kilocalories
galactose + glucose =
lactose
maltose
least common formed from digestion of starches
benefits of legumes and nuts
legumes provide 4 grams of fiber per serving -nuts and seeds contain little starch but a lot of fiber
sources of oligosaccharides
legumes, beans, cabbage, brussels sprouts, and broccoli found in human breast milk
where is glycogen stored?
liver and muscle
how does fiber help prevent heart disease
• Viscous, soluble fiber helps lower elevated blood cholesterol levels. • Soluble fiber interferes with the reabsorption of bile acids, which contain cholesterol, by sequestering the bile acids. • Fiber and bile acids are excreted in the feces. • Slow-moving, viscous, soluble fiber may reduce the rate at which fat and carbohydrate are absorbed. • Decreasing the level of fat in the blood and improving insulin sensitivity may decrease the risk of heart disease. • Insoluble fiber has been shown to promote heart health.
benefits of whole grains
• Whole grains are abundant in complex carbohydrates, including starch and fiber. • Whole grains are associated with reduced risk of chronic diseases.
examples of whole grains
• Whole-grain breads and cereals with 2 to 3 grams of fiber per serving • Bulgur, brown rice, quinoa, oatmeal, and whole-wheat pasta