What are carbohydrates?
nutrients that meet the body’s energy needs, feed the brain and the nervous system, keep the digestive system fit, and keep your body lean
What are the monosaccharides?
Glucose, fructose, and galactose
What are the dissaccharides?
Lactose, maltose, and sucrose
Difference between a monosaccharide and disaccharide
-monosaccharides are single sugar rings that are absorbed directly into the blood
-disaccharides are multiple sugar rings linked together that are digested & broken down by enzymes
What is the storage form of CHO in the human body?
glycogen
Which macronutrient do the brain and nervous system prefer as their fuel source?
carbohydrates
What organ releases the hormones that regulate blood glucose? What are those hormones, and when are they released in the body?
The pancreas and it makes insulin and glucagon
Insulin is released when the blood sugar is high
Glucagon is released when the blood sugar is low
Which enzyme in the mouth is responsible for splitting the starch molecules into smaller units for further digestion?
salivary amylase
What does insulin do for the body?
lower the blood glucose when too high
What does glucagon do for the body?
raises the blood glucose when too low
Lactose intolerance
impaired ability to digest lactose due to reduced amounts of the enzyme lactase
How do insulin and glucagon affect blood glucose?
they each keep the blood glucose at a stable range
What nutrients were added to refined grains as a part of the U.S. Enrichment Act?
1942: iron, thiamin, riboflavin, and niacin
1996: folate added to the list
How does the body handle excess glucose?
-Body tissue shift: the liver will turn extra glucose into fat
-carbohydrate and weight management: carb is stored as fat, and weight is maintained through dietary importance and composition
Why does fiber lower your cholesterol?
The more fiber you eat the more cholesterol can exit the body in bile.
Characteristics of Type 1 diabetes
blood glucose styes too high, lacking insulin, immune system attacks and destroys insulin producing cell in the pancreas as if they were foreign cells
Characteristics of Type 2 diabetes
blood glucose stays too high, cells do not respond to normal insulin levels often diagnosed in adulthood, occurs as a consequence of obesity
What is ketosis?
an undesirably high concentration of ketone bodies, such as acetone, in the blood or urine
What is protein-sparing action?
the body's ability to make sure that the proteins that the body acquires through food are not converted into energy molecules
GLUT 4
primarily expressed in adult tissues that exhibit insulin-stimulated glucose transport, such as adipose tissue and skeletal and cardiac muscle.
How does fiber aid in digestion and absorption?
fiber slows down digestion so that the body can absorb more nutrients from the food
3 classes of lipids
triglyceride
phospholipids
sterols
Cholesterol
a member of the group of lipids known as sterols; a soft, waxy substances made in the body and also found in animal-derived foods
What is a triglyceride?
saturated fatty acid
Level of saturation/unsaturation
saturated: no double bonds, solid at room temp.
unsaturated: double bonds, create kinks and results in bent structure
Phospholipids
polar and nonpolar portion to form membranes around the cellular components
What is an emulsifier?
A substance that stabilizes an emulsion is a food additive used to stabilize processed foods.
What is the importance of bile, and what it does it in the body?
Aids with digestion. It breaks down fats into fatty acids, which can be taken into the body by the digestive tract.
What enzyme is released to begin the breakdown of triglycerides?
lipase
How is fat digested and absorbed?
mouth: breaks down TGs with lingual lipase
stomach: acts of TGs with medium chain with gastric lipase
small intestine: main site for fat digestion
Role of CCK
stimulates release of pancreatic lipase and bile
low-density lipoproteins(LDL)
larger, lighter, and richer in cholesterol
high levels trigger inflammation and heart disease
high-density lipoproteins(HDL)
smaller, denser, and packaged with more protein
high levels oppose heart disease and vice versa
Which lipoprotein is considered “bad” cholesterol and why?
LDL: it increases the risk factor for atherosclerosis and cardiovascular disease
Which lipoprotein is considered “good” cholesterol and why?
HDL: decreases the risk factor of atherosclerosis and cardiovascular disease
Omega-3 fatty acids
given dietary linolenic acid, the body can make other members
What do the Dietary Guidelines for Americans say about saturated fat?
consume less than 10 percent of calories per day from saturated fats
What happens when someone is deficient in essential polyunsaturated fatty acids, linoleic, and linolenic acids?
-cause skin abnormalities and poor wound healing
-in infants, growth is delayed, and vision is impaired
-the body stores some essential fatty acids, so deficiencies are almost unknown among healthy adults
What foods contain abundant amounts of EPA DHA?
almon, tuna, mackerel, and pollock