Exam 2

What are other names for omega-3 and omega-6 fatty acids and what is the difference between the two?

Omega- 3 is also known as linolenic acid and omega-6 is also known as linoleic acid. Unsaturated fatty acids, such as omega-3 and omega-6, are named after the location of the first double bond (counting from the non-acid end) between carbon atoms in the carbon chain. In omega-3 fatty acids the first double bond is between the third and fourth carbons and in omega-6 the first double bond is between the sixth and the seventh carbons. The difference in structure changes the way these fatty acids are used in the body.

Which function of fats allows a person to ride a mountain bike for many hours without harming their internal organs?

Padding

In the U.S. which group is most likely to get scurvy?

People addicted to alcohol

The text indicated specific reasons why taking massive doses of vitamin C can be dangerous. Based on this information, what group (or groups) should be particularly careful not to take in too much vitamin C?

People with too much iron in their blood People with kidney disorders

Which is true about amino acid supplements?

The body can handle whole proteins better than amino acid supplied in supplements. (body better at breaking down whole proteins into amino acids instead of supplements)

The B vitamins act as part of:

co-enzymes

LDL

combines with cholesterol and transport from liver to cells; bad fat sticks to walls

DRI for Protein

.8 g per 1 kg (2.2 lbs)

What benefit is associated with increasing the proportion of dietary fats coming from omega-3 sources and reducing the proportion coming from omega-6 sources?

- Decreased formation of undesirable blood clots - Lower blood pressure - Reduced inflammation

What is the AMDR for fat intake?

20-35%

What are the health benefits and/or health risks of consuming saturated and unsaturated fatty acids?

A diet high in saturated fats is associated with high risks for cardiovascular disease. Saturated fat causes the body's blood lipids to shift towards an unhealthy profile, whereas a diet high in unsaturated fats lowers the risk of cardiovascular disease and shifts the blood lipid profile to a healthier range.

Who would be most likely to develop pellagra?

A person who eats no meat and eats corn as their dietary staple

According to the textbook, which supplement would be best?

A supplement that has less than the DRI of every nutrient for your gender and age

Which describes a polyunsaturated fatty acid? A. A fatty acid with two or more double bonds B. A fatty acid with numerous hydrogen atoms C. A fatty acid with two or more carbon atoms D. A fatty acid with numerous acid groups

A. A fatty acid with two or more double bonds

What is the function of bile? A. Emulsify fat so it can be more easily digested B. Digest proteins to peptides and amino acids C. Digest glycerol to individual fatty acids D. Transport fat soluble compounds in the GI tract

A. Emulsify fat so it can be more easily digested

Generally speaking for the population, which contributes most to high blood cholesterol? A. Intake of saturated and trans fats B. Intake of polyunsaturated fats C. Intake of cholesterol D. Intake of monounsaturated fats

A. Intake of saturated and trans fats

Which of the following would provide the highest amount of vitamin E? A. Mayonnaise B. Whole milk C. A pork chop D. A grilled chicken leg

A. Mayonnaise

What foods are sources of saturated fats? Monounsaturated fats? Polyunsaturated fats?

Animal fats tend to contribute substantial amounts of saturated fats, with some notable exceptions. Coconut oil is very high in saturated fat, and palm oil also is a contributor. (These are sometimes called tropical oils.) Olive oil and canola oil are notable for their monounsaturated fat content. Other plant seed oils such as safflower, sunflower, corn, soybean, and cottonseed oil all are high in polyunsaturated fats

Which is accurate about food sources of lipids? A. Olive oil is a significant source of saturated fat. B. Beef fat (tallow) is a significant source of saturated fat. C. Legumes are a significant source of omega-3 fatty acids. D. Stick margarine is a significant source of cholesterol.

B. Beef fat (tallow) is a significant source of saturated fat.

Which recommendation is consistent with recommendations for fish or fish oil intake? A. Consume fish oil supplements instead of fish because they are a more concentrated source of omega-6 fatty acids. B. Eat two meals each week of fatty cold water fish. C. Frying fish in vegetable oil improves the fatty acid profile by contributing omega-6 fatty acids.

B. Eat two meals each week of fatty cold water fish.

Which statement is consistent with Dietary Guidelines and USDA Food Patterns recommendations? A. You should eliminate saturated fat completely from your diet. B. It's OK to have 30% of your calories from fat. C. Eat fried fish about twice a week to get enough omega-6 fats. D. Eat mild-flavored cheeses more often to increase intake of omega-3 fats. Fat replacers should be used whenever possible as this will decrease chronic disease risks.

B. It's OK to have 30% of your calories from fat.

Which suggestion is consistent with the Dietary Guidelines and USDA Food Patterns recommendations? A. Minimize intake of nuts, olives, avocados and other fatty plant foods. B. Minimize the use of shortening and other solid fats. C. Keep total fat intake below 10% of calories

B. Minimize the use of shortening and other solid fats.

Which food is most likely a source of trans-fatty acids? A. Yogurt B. Stick margarine C. Cheese D. Ground beef

B. Stick margarine (Trans-fatty acids are formed when unsaturated fats are hydrogenated)

Which vitamin deficiency is associated with nerve damage and anemia?

B12

What is the role of phospholipids in the body?

Because of its structure, phospholipids are soluble in both fats and water. This allows it to act as an emulsifier, or a substance that mixes with both fat and water and permanently disperses the fat in the water. This ability to dissolve in both fats and water is important in cell membranes, to allow fats to travel back and forth across the lipid-containing cell membranes into the watery liquids on both sides.

Which food contains low quality protein? A. Turkey B. Eggs C. Corn D. Fish

C. Corn

Which of these foods would be the best source of Vitamin B12? A. Whole wheat bread B. Red bell pepper C. Cottage cheese D. Legumes

C. Cottage cheese (animal products)

Which diseases will vitamins CURE? A. Cancers B. Hypertension C. Deficiency diseases D. Cardiovascular disease

C. Deficiency diseases

Which statement is accurate about protein digestion and absorption? A. Protein digestion first begins in the acidic environment of the small intestine. B. Polypeptides are much better absorbed by the small intestine than single amino acids. C. Whole proteins are digested and absorbed better than amino acid supplements. D. The nitrogen group is removed before amino acids can be absorbed.

C. Whole proteins are digested and absorbed better than amino acid supplements.

Vitamin C

CCC Function: connective tissue Deficiency: scurvy Toxicity: none Source: citrus, acidic foods

What foods are high in omega-3 fatty acids? In omega-6 fatty acids?

Canola oil is a plant source of omega-3 fatty acids, and fatty fish from cold, deep water are an even richer source. (But fast food fish, fried fish, and many frozen fish products come from varieties of fish that are not particularly rich in omega-3 fatty acids, and frying usually only adds more omega-6 fatty acids from the oils used in frying.) Omega-6 fatty acids come from most vegetable oils.

What are the structural characteristics of cholesterol? What compounds in the body are formed from a cholesterol precursor?

Cholesterol has a completely different chemical structure from triglycerides: it consists of interconnected rings of carbon atoms with side chains of carbon, hydrogen, and oxygen attached. Bile, vitamin D, and sex hormones are all made in the body from cholesterol. Cholesterol is also part of the cell membrane.

What foods are sources of cholesterol? What is the relationship between dietary intake and blood cholesterol?

Cholesterol is only found in foods of animal origin, so it is found in meat, poultry, fish, eggs, milk, cheese, and butter, but not in margarine, nuts, avocados, olives, and legumes. For most people dietary cholesterol has little relationship to blood levels of cholesterol. Except for some people who have a genetic predisposition toward high blood cholesterol, high intakes of saturated and trans fats are much more important in affecting blood cholesterol.

What are the various kinds of lipoproteins? What does each transport, to where?

Chylomicrons deliver recently-absorbed dietary fats to tissues, via the lymph and blood. VLDL (very low density lipoproteins) carry triglycerides and other lipids made in the liver to cells throughout the body. LDL (low-density lipoproteins) deliver cholesterol and other lipids to tissues. HDL (high-density lipoproteins) pick up cholesterol from cells and deliver it to the liver for disposal

What health problems are linked with trans-fatty acids formed during hydrogenation of plant oils? What foods are most likely to contain trans fats?

Consuming trans-fatty acids poses a risk to the heart and arteries by raising blood LDL cholesterol and lowering beneficial HDL cholesterol. It may also increase tissue inflammation. Hydrogenation of unsaturated fats produces some trans-fatty acids, so they are found most often in commercially fried foods and in baked goods and other commercial foods made with partially hydrogenated vegetable oils.

Which vitamins participate in bone growth?

D, K, C

Which is accurate about triglycerides? A. Each triglyceride has one saturated, one monounsaturated, and one polyunsaturated fatty acid. B. Triglycerides are found in plant oils but not in animal fats. C. All the fatty acids in the molecule will be identical. D. The types of fatty acids determine the hardness or softness of the fat.

D. The types of fatty acids determine the hardness or softness of the fat.

How does celiac disease affect the body?

Eating the protein gluten causes autoimmune response that decreases nutrient absorption.

What are the health advantages of increasing the proportion of omega-3 fats in the diet, relative to omega-6 fats?

Eicosanoids are regulatory compounds made from certain fatty acids. The omega -3 fatty acids EPA and DHA, found mainly in fatty fish, make eicosanoids that appear to lower blood pressure, prevent blood clot formation, and protect against irregular heartbeats. These are beneficial effects related to several chronic diseases. On the other hand, if most of the eicosanoids are made from omega-6 fatty acids, they have some negative effects. For health, people need the right balance of omega-3 and omega-6 fatty acids in the diet. The balance between the two fatty acids can be improved by eating fatty fish several times each week.

What are the functions of fat in the body?

Fat is the major source of energy for the body, both for immediate use and stored in adipose tissue for later use. Adipose tissue provides padding and protection for internal organs as well as insulation from extreme temperatures. They are the carriers for the fat soluble vitamins and they proved the two essential fatty acids

What is the main structure of fatty acids?

Fatty acids are carbon chains of different lengths, with an acid group at one end

What benefits are associated with eating fish twice a week?

Fish, especially fatty cold-water fish, are high in the omega-3 fatty acids DHA and EPA. These omega-3 fatty acids help prevent heart disease by lowering blood pressure, preventing blood clot formation, and protecting against irregular heartbeats. Eat fatty fish, preferably grilled, baked, or broiled: the varieties of fish most often prepared this way contain more EPA and DHA than species used for frying or in frozen fish products.

Which vitamin deficiency is associated with a higher risk of neural tube defects?

Folate

Vitamin A

Function: Cell differentiation, gene expression, vision Deficiency: Night blindness, total blindness Toxicity: miscarriage, kidney failure, liver damage Source: orange, dark, green leafy (betacarotene = 2 A)

Vitamin E

Function: antioxidant Deficiency: none Toxicity: thin blood Source: plant oils

Vitamin K

Function: blood clotting Deficiency: thin blood Toxicity: thick blood Source: green leafy vegetables, bacteria (baby shots)

Vitamin D

Function: calcium regulation (kidney, bones) Deficiency: rickets (kids), osteomalacia (adults) Toxicity: calcification of soft tissue Source: sun, fortified dairy

Vitamin B12

Function: co-enzyme activates folate Deficiency: anemia, nerve damage Toxicity: none Source: animal products

Thiamin

Function: co-enzyme in energy metabolism Deficiency: Beri Beri Toxicity: none Source: grains

Niacin

Function: co-enzyme in energy metabolism Deficiency: DDDD (death, diahrhea, dimensia, dermatitis) pellagra Toxicity: none Source: protein

Folate

Function: co-enzyme in energy metabolism Deficiency: anemia, neural tube defects Toxicity: none Source: green leafy (Foliage)

Riboflavin

Function: co-enzyme in energy metabolism Deficiency: none Toxicity: none Source: dairy (destroyed by light)

Vitamin B6

Function: metabolic processes Deficiency: none Toxicity: nerve damage, depression Source: everything

What are the recommendations regarding fat intake?

Generally the total fat intake should between 20-35% of total calories,, mostly from mono- and poly-unsaturated fats. Saturated fat intake should be less than about 7-10% of total calories. Increase the ratio of omega-3 fatty acids to omega-6 fatty acids. Keep trans fat intake as low as possible, and minimize cholesterol intak

What is the recommendation concerning the ratio of saturated fat to unsaturated fat in the diet?

High unsat and low sat

Why are plant oils hydrogenated?

Hydrogenated fats are less likely to develop rancid flavors and they are easier to spread, contributing pleasing textural characteristics to foods.

What happens to lipids after they are absorbed from the small intestine?

In the cells lining the small intestine, triglycerides are reassembled from the parts. The small molecules of short-chain fatty acids and glycerol are absorbed into the blood stream and delivered to the liver. The triglycerides are combined with protein to from lipoproteins which are absorbed into the lymph system and eventually delivered into the blood stream.

Who will benefit from a gluten-free diet?

Individuals with celiac disease

What is a function of Vitamin E?

It helps stop destructive chain reactions that can damage cell membranes, DNA, and cellular proteins.

What is the main function of vitamin K?

It helps synthesize proteins that are needed for blood to clot.

What does hydrogenation do to fatty acids?

It makes them resistant to oxidation. (Hydrogenation is the process of adding hydrogen atoms to an unsaturated fatty acid to produce a more stable fat which is less subject to oxidation and rancidity. Because the fat is now more saturated, any health benefits associated with the original plant oil are actually decreased)

Several connections have been suggested between a HIGH protein intake and disease risk. Which health problem is most strongly linked with a high protein intake from meat?

Kidney damage if someone already has kidney disease

How can someone increase their HDL values?

Lipid intake has little influence on blood HDL levels. Regular physical activity helps increase blood HDL levels.

What are lipoproteins?

Lipoproteins are clusters of lipids and protein. They make it possible for fats to be transported in watery lymph and blood.

What are the steps of lipid digestion? Where do they occur?

Little digestion occurs until the lipids reach the small intestine. There bile (produced by the liver and stored in the gall bladder until needed) is released into the small intestine and emulsifies fat so that it can be mixed with the watery fluids. Fat-digesting enzymes break down triglycerides into free fatty acids, glycerol, and monoglycerides which can be absorbed by the cells lining the small intestine.

What is the difference between saturated and unsaturated fatty acids? Between monounsaturated and polyunsaturated fatty acids?

Most of the carbon atoms in a fatty acid are connected with single bonds. When there are no double bonds between carbon atoms, it is called a saturated fatty acid (the carbon chain is "saturated" with hydrogen atoms). If there is one double bond between carbon atoms, it is called a monounsaturated fatty acid, and if there are 2 or more double bonds it is called polyunsaturated fatty acid

What part of amino acids is excreted in urine when amino acids are degraded?

Nitrogen

Holly has decided she wants to lose fat and so she decides to eliminate as much fat from her diet as possible, aiming for a fat intake of less than 10% of her calories. Is this a wise approach? Why or why not?

No, she would not have the recommended amount of calories coming from fat.

What is the best natural (unfortified) source of folate?

Raw Spinach

What makes protein DIFFERENT from other macronutrients?

Protein contains nitrogen.

Which nutrients are of concern with vegetarian diets?

Protein, zinc, calcium, vitamin B12

What determines how hard or soft a fat is at room temperature?

Shorter chain fatty acids and fatty acids that are unsaturated tend to be softer and melt more easily at lower temperatures. Longer chain and saturated fatty acids tend to be hard at room temperature.

How does a traditional Mediterranean diet help meet recommended fat intakes? What are the limitations in applying its benefits to Americans?

The main fat in the traditional Mediterranean diet is olive oil. This cuisine also includes generous intakes of pastas and whole grain breads, nuts, fruits, greens, and other vegetables. Legumes, cheeses, yogurt, and some fish and poultry are included. This diet is also low in red meats. The limitation of this diet is that it was eaten by people living a labor-intensive but less rushed lifestyle than is available to most Americans, Some of the dietary benefits attributed to the diet may come from the total lifestyle pattern that accompanied it - a lifestyle which is not followed by most Americans.

How does hydrogenation change the structure of fatty acids? What are trans-fatty acids?

The process of hydrogenation breaks some of the fatty acids' double bonds and adds hydrogen atoms to the molecule. This makes the oil more saturated, and more solid at a lower temperature. Not all of the double bonds are broken during this process, and some of the remaining double bonds have a shift in their chemical structure: instead of the normal bend in the 3-dimensional configuration at double bonds, the molecules are straightened out. This straightening out is a result of the hydrogen atoms being on opposite sides of the carbon bond, thus they become trans-fatty acids

What happens if the structure of a protein in the body is altered?

The protein cannot be used for its original function.

Which factor influences the protein quality of a food?

The protein's digestibility

What are the main categories of lipids?

The three classes of lipids are triglycerides, phospholipids, and sterols. Fatty acids are not a main category, but they constitute an important part of triglycerides

Which aspect of vegetarian diets is correlated with lower heart disease risks?

They are low in saturated fats.

What makes certain amino acids essential to the body?

They are not synthesized by the body in sufficient amounts.

In general, how can one recognize saturated fats?

They are solid at room temperature

What is true concerning fat soluble vitamins?

They are stored in the liver and fatty tissues and do not need to be supplied every day.

How can nutrient supplements be dangerous to overall health?

They can interfere with the use of other vitamins.

What are the functions of fat in foods?

They contribute to the energy value of foods and to satiety after eating. They provide flavors, aromas, and smooth and moist textures. They carry the fat-soluble vitamins and assist in their absorption.

Which is true about complementary proteins?

They provide all the essential amino acids.

Which vitamin deficiency leads to beriberi?

Thiamin

What are the structural characteristics of triglycerides?

Triglycerides consist of 3 fatty acids attached to a 3-carbon glycerol molecule. A triglyceride can have any three fatty acids attached to the glycerol -- they do not have to all be the same. The types of fatty acids determine the hardness or softness of the fat.

Which of the following is a major difference between triglycerides and phospholipids?

Triglycerides have three fatty acids attached to the glycerol whereas phospholipids have one of the fatty acids replaced by a phosphate group.

A girl has stopped growing in height prematurely because her bones are not being remodeled normally. Which vitamin deficiency might cause this?

Vitamin A

Which vitamin cannot be absorbed when the intrinsic factor is lacking?

Vitamin B12

Women taking vitamin supplements over several years to help with PMS symptoms developed problems with numbness in their hands and feet and were then unable to walk. Which vitamin in the supplement was most likely to cause the symptoms?

Vitamin B6

Which vitamin can the body make?

Vitamin D

Which vitamin deficiency results in rickets?

Vitamin D

Which vitamin is obtained from intestinal bacteria?

Vitamin K

When does negative nitrogen balance occur?

When muscle is broken down and lost

Who are most likely to have positive nitrogen balance?

children, pregnant women

Where does protein digestion begin?

stomach where acid denatures protein

What are the function of protein?

support growth, provide energy, maintain acid-base balance, increase metabolism

HDL

transport excess cholesterol out of body