Module 2
A. Introduction to Carbohydrates
Popular diets and weight loss programs wrongly place carbohydrates in the "bad food"
category. Of course, we know from Module 1 that categorizing foods as good and bad is a red
flag of nutrition misinformation - like most nutrition misinformation, the claims against
carbohydrates oversimplify a complex topic. As the video above indicated there are three
categories of carbohydrates - simple sugars, starch and fiber. Perhaps some of the confusion
about carbohydrates stems from the fact that they are found in many foods - some healthy
and some not.
Carbohydrates have always been an important part of the human diet. Carbohydrate is an
important energy source - in fact, our brain and red blood cells rely solely on carbohydrate for
fuel. In many parts of the world, where diets consist primarily of grains and plant foods, as
much as 80% of energy needs come from carbohydrates. Our Western diet includes more
meat and dairy products, so in the U.S., about 50% of calories come from
carbohydrates. Sources of carbohydrate are plant foods - grains, legumes, fruits, vegetables
and milk. Fats, oils and meats do not contain carbohydrate.
Below is the average amount of carbohydrate found in foods (from the U.S. Diabetes
Exchange System):




Milk - 12 grams of CHO per serving
Grains - 15 grams of CHO per serving
Fruit - 15 grams of CHO per serving
Vegetables - 5 grams of CHO per serving
The USDA Food Guide includes generous amounts of fruit, vegetables, grains and milk. These
foods, in addition to being high in carbohydrates, are excellent sources of many nutrients
including dietary fiber, thiamin, niacin, riboflavin, folate, Vitamin A(beta- carotene),
magnesium and protein. Other foods, particularly those with added sugar, are high in
carbohydrates, but low in nutrients. Foods such as candy, sugar-sweetened beverages (juice
drinks, soda, etc.), sweetened cereals, cookies and cakes are poor carbohydrate
choices. These foods contain a lot of calories for the few nutrients they supply. People who
think carbohydrates are "bad" are usually thinking about these foods, not realizing that many
healthy foods are also high carbohydrate foods.
RECOMMENDATIONS:
The DRI include two different recommendations for total carbohydrate.
1. The RDA is set at 130 grams of CHO per day for adults. This is the minimum amount of
carbohydrate needed to provide the brain with fuel. Intake of less than 50 grams/day
can create a condition called "ketosis. Ketosis is a process that happens when your
body doesn't have enough carbohydrates to burn for energy. Instead, it burns fat and
makes things called ketones, which it can use for fuel but can have adverse effects.
2. The DRI includes an AMDR (Average Macronutrient Distribution Range) for
carbohydrates set at 45 - 65%. That is: Carbohydrate should supply 45% - 65% of total
calories. On a 2000 calorie diet, that is 225-325 g/day or 900-1,300kcal/day
So, the RDA in this case is a minimum recommendation. The optimum CHO intake is between
45 - 65% of total calories.
B. Energy nutrient storage
Energy Nutrient Storage
The body converts excess glucose into glycogen which is stored in the liver and muscles. This
process of moving glucose in the blood to cells, is facilitated by the hormone insulin. The
amount of glycogen that can be stored is limited by our muscle mass.
Fat is stored in the body in different compartments. The two main compartments are
subcutaneous (under the skin) and visceral or abdominal (around the internal organs). Fat can
also “overflow” into other areas of the body, the liver, pancreas, muscles. Basically, we can
store a lot of fat!!!!
Protein, simply put, is not stored. Any protein we have in our body is being used to perform
functions that only protein can perform. Therefore, we do not want to depend on protein for
energy.
Below a Healthy Minimum
Glucose can be converted into body fat; body fat cannot be converted into glucose to feed the
brain adequately. When the body faces a severe carbohydrate deficit, it has two problems.
Having no glucose, it must turn to protein to make some (the body has this ability), diverting
protein from its own critical functions, such as maintaining immune defenses. When body
protein is used, it is taken from blood, organ, or muscle proteins; no surplus of protein is stored
specifically for such emergencies. Protein is required to maintain normal body functions, and
carbohydrate should be kept available precisely to prevent the use of protein for energy. This is
called the protein-sparing action of carbohydrate. As for fat, it regenerates a small amount of
glucose—but not enough to feed the brain and nerve tissues. When protein is used to produce
glucose, the nitrogen is removed from the protein structure which increase the nitrogen load
that the kidneys need to clear.
Ketosis
With too little carbohydrate flowing to the brain, the body will metabolize fat products, known
as ketone bodies , for energy in place of some of its glucose. Instead of producing energy by
following its main metabolic pathway, fat takes another route in which fat fragments combine
with each other. This shift leads to an accumulation of the normally scarce ketone bodies in the
blood, a condition known as ketosis .
When acidic ketone bodies build up to high levels in the blood, as they can in untreated
diabetes, they disturb the normal acid-base balance, a life-threatening situation. To defend
itself from this harm, a healthy body excretes excess ketone bodies in the urine, a process that
also removes water and minerals. Over time, people eating diets that produce ketosis may
develop deficiencies of minerals, particularly bone minerals, and may suffer other adverse
effects (more on this in Chapter 9.) The popular low carb also called ketogenic diets depend on
the process of using fat products for energy. They also increase protein diet which can be used
for glucose production. But again, nitrogen is removed from the protein structure which
increases the work of the kidneys.
Ketosis isn’t all bad, however. Ketone bodies provide a critical fuel alternative to glucose for
brain and nerve cells when glucose is lacking, such as in periods of fasting or in starvation. Not
all brain tissues can use ketones—some rely exclusively on glucose, so the body must still
sacrifice some protein to provide it—but at a slower rate. A therapeutic ketogenic diet has
substantially reduced seizures in children and adults with epilepsy, although many find the diet
difficult to follow for long periods.
C. Fiber
One benefit of eating a diet high in carbohydrates, as recommended by the Dietary Guidelines
and MyPlate, is that many foods that are high in carbohydrates are also good sources
of dietary fiber. Fibers, like starches, are complex carbohydrates - long chains of many
glucose units connected. There is one important difference, however. Our bodies do not
produce enzymes that can break apart fiber, therefore we are unable to digest or absorb
fiber. Fiber is carried out of the body as waste. Fiber does provide some important functions:
1. Fiber absorbs glucose, slowing the absorption of glucose from the GI tract which help
prevent a spike in blood glucose levels. A benefit for diabetics;
3. absorbs cholesterol and other fats and carries them out of the body as waste;
3. exercises the GI muscles improving the elimination of waste;
Fiber is categorized as either soluble or insoluble, depending on whether it dissolves in
water. Both soluble and insoluble fiber are valuable components of a healthy diet. The FDA
allows several health claims for high fiber foods, based on strong scientific evidence that fiber
provides important health benefits. (If you don't remember what a health claim is - go back
and review the information on food labeling.) Evidence suggests that:

soluble fiber from oats, apples and fruit pectin may reduce the risk of heart disease.

dietary (insoluble) fiber from whole grains, fruits and vegetables may reduce the risk
of heart disease and some cancers.
Soluble fibers can ferment in the large intestines. Their bi-products can:



nourish cells of the colon and promote resistance to colon cancer;
reduce inflammation;
support immunity.
Dietary Fiber Recommendations:

The Dietary Reference Intakes (DRI) sets an Adequate Intake (AI) for Total Fiber
between 25 - 38 grams per day. This recommendation is based on 14 grams of fiber
per 1000 calories, so men and very active people eating more calories should consume
more fiber.
Most Americans consume less than the recommended amounts of Dietary Fiber, although
fiber is quite easy to come by in many foods. The best sources of fiber are whole grains,
legumes, fruits and vegetables. Eating according to the food intake patterns from MyPlate,
including the advice to "Make Half Your Grains Whole Grains", ensures an adequate intake for
dietary fiber.
The following foods supply the recommended amount of fiber for an adult:
Fruit 2 servings, grams of fiber/serving
1 Apple 4 g
1 C Blueberries 4 g
Vegetables 3 servings, grams of fiber/serving
1 Baked potato 5
1/2 C Beets 1
1/2C Beans 2
Bread and grain 6 servings, grams of fiber/serving
1 C oatmeal 4 g
1 flour tortilla 2 g
1 bagel=2 servings 2 g
2 sl wheat bread 4 g
How much fiber do you typically eat? The fiber hunt assignment may help you discover this.
D. Lactose Intolerance
Lactose, commonly called milk sugar, is the primary carbohydrate found in milk. Lactose is a
disaccharide, it must be split by digestive enzymes into the monosaccharides glucose and
galactose before it can be absorbed. Lactase is the digestive enzyme needed to digest and
absorb lactose.
Lactose intolerance is a disorder where the individual does not produce the enzyme lactase
which is necessary for the digestion of the milk sugar lactose. The result is, that the lactose is
fermented by bacteria in the GI which causes diarrhea, cramping, gas, nausea, stomach
distention and general GI discomfort. The concern we have for people with this disorder is that
that are at risk for calcium and vitamin D deficiencies as well as inadequate protein and
riboflavin intake. These deficiencies could develop into rickets in children, osteomalacia in
adults and is a risk factor for osteoporosis in older adults. According to the Cleveland Clinic,
more than 30 million American people are lactose intolerant. The condition isn’t serious but
may be unpleasant and should be addressed.
People with a lactose intolerance need to avoid or restrict lactose containing foods but ensure
they are getting an adequate intake of calcium and vitamin D. Foods that contain lactose can
be treated with enzymes that breakdown the lactose. 'Lactaid' is milk that has been enzyme
treated. Alternatively, lactose intolerant individuals can take a lactase enzyme tablet along
with lactose containing foods.
People who are lactose intolerant need to be certain that their diet contains an adequate
amount of calcium and Vitamin D through other food sources, fortified foods such as breakfast
cereals, exposure to sunlight (for Vitamin D), and supplements, if needed. Fermented cheese
and yogurt often are tolerated since the processing of these products breakdown the
lactose. Fish can also provide calcium and vitamin D. Green vegetables can supply
calcium. Milk substitutes such as oat, almond or soy milk often have vitamin D and calcium
added, but check to make yours does.
It's not uncommon for a newborn to have symptoms but generally outgrow the lactose
intolerance by the age of two. Additionally, as we age, we may develop a mild lactose
intolerance, especially after the age of 65.
There are certain ethnic groups that are at greater risk, they are:
· Those of Mediterranean origin
· African Americans
· Asians
· Jews
· Mexicans
· Native Americans
The medical nutrition therapy which relieves symptoms and provides adequate calcium and
vitamin D is to restrict lactose containing foods(unless enzyme treated), consume foods that
provide calcium as well as vitamin D, supplement the diet in calcium and vitamin D and get
regular exposure to sunlight.
Diet requirements:
· Avoid milk and cream (and their products such as ice cream), unless treated with lactase
enzymes, although some people may be able to handle 1/2 cup of milk day.
· Generally aged cheese and yogurt is well tolerated(but often does not contain vitamin D)
· Consume fortified breakfast cereal, sardines, canned tuna and salmon for calcium and vitamin
D as well as other products that have calcium/and or vitamin D added such as orange
juice. Green leafies also have calcium but not vitamin D.
· If intake is still poor supplements should be used. But it is always best to get our nutrients
from food.
E. Sugar, Sugar and More Sugar
There are few foods that bring out as many strong reactions as sugar. Human beings naturally
like sweet tastes and most of us enjoy celebrating with sweet treats - birthday cakes, wedding
cakes, ice cream at the beach, Holiday cookies and more! At the same time, sugar is often
viewed as "bad" food, responsible for a whole range of problems. Should we feel guilty
enjoying sugar? How much is too much?
The 2010 Dietary Guidelines use the acronym SoFAS, referring to "Solid Fats and Added
Sugars". Added Sugars are:

sugar we add to foods at home (sugar in coffee, honey in tea, brown sugar on oatmeal,
syrup on pancakes)

sugar and other forms of sweeteners found in packaged foods and restaurant foods
(including baked goods, candy, sweetened cereals, ice cream, soft drinks, and many
foods marketed to children)
The USDA estimates that as much as 35% of the average Americans calories come from
SoFAS. Where only 5-15% should be a part of our diet. Examine some food labels the next time
you are in the grocery store and you will see that there are many forms of sugar in our food
supply - including table sugar, brown sugar, high fructose corn syrup, honey, syrup, molasses,
dextrose, sucrose.... and that is just a start. Because there are so many forms of sugar found in
so many different foods, it is very easy to get too much of it. Sugar sweetened beverages, like
soda are a good example of this - a person who drinks two 12 oz. cans of soda a day is
consuming 300 calories from sugar. Many public health experts believe that sugar sweetened
beverages are a large part of the obesity problem in the U.S. and support the idea of a "soda
tax" to discourage consumption of excessive amounts of soft drinks.
There are two main problems associated with Added Sugars in the diet:
1. Added Sugars provide calories but no nutrients. If a person meets most of their
energy(kcals) needs by eating foods high in added sugars, they are unlikely to consume enough
nutrients.
2. Frequently eating foods high in sugar (and starch) plays a big part in the development of
dental caries. The worst foods for dental health are sticky, sweet foods that stay in the mouth a
long time...think fruit snacks, gummy bears, tootsie roll pops.
There is no truth behind the notion that sugar causes hyperactivity in children, although many
people continue to believe this myth.
Aspartame, a low calorie sugar substitute is made from the amino acids phenylalanine and
aspartic acid. Individuals with PKU(phenylketone urea) cannot metabolize phenylalanine and
must avoid, as much as possible, this substance. They should avoid diet soda since most of it
contains phenylalanine found in nutra-sweet.
Embedded Video Player: Episode 524: Dr. Nicole Avena- How Sugar Affects the Brain
Episode 524: Dr. Nicole Avena- How Sugar Affects the Brain
User: n/a - Added: 6/9/17
Added Sugar Recommendations:
DRI - No set number for Added Sugars, but recommends a maximum of 25% of calories from
Added Sugars (based on studies that show nutrient intakes suffer when Added Sugar intake is
higher than this).
Dietary Guidelines/MyPlate - includes 5 to 10% of calories from Added Sugars (counted as
Empty Calories)
Current issue:
A popular idea that is currently taking hold is taxing sugar sweetened beverages, usually soda,
as a means to raise money and to decrease public consumption. This is similar in many ways to
what happened with cigarettes. The Governor of New York State unsuccessfully attempted to
do this in the fall of 2009; however, we have not heard the last of this issue.
ONE LAST THING.....try this experiment. Take a clear drinking glass. Place into it the amount
of sugar that you put in your coffee or tea (use a teaspoon measure), then continue adding
teaspoons of sugar to equal ten. Ten teaspoons of sugar is how much you get from one 12
ounce Coke, Pepsi or similar soft drink. The average person puts no more than four
teaspoons of sugar in their coffee or tea. How do you feel about drinking a beverage with so
much sugar?
Interesting information on sugar intake, please connect to and read or listen to the NPR show.
http://www.npr.org/sections/thesalt/2016/01/07/462160303/new-dietary-guidelines-crackdown-on-sugar-but-red-meat-gets-a-pass
New Recommendations for Kids and Eating Sugar. This video is very important to view!!!
http://abcnews.go.com/GMA/video/recommendations-kids-eating-sugar-41582194
F. American Heart Association Article on fiber
Understanding Whole Grains, Fiber
Eating whole grains every day increases fiber and can help improve your heart health. Any food
made from wheat, rice, oats, corn, or another cereal is a grain product. Bread, pasta, oatmeal
and grits are all grain products. There are two main types of grain products: whole
grains and refined grains.
Whole grains contain the entire grain – the bran, germ and endosperm. Examples include
whole-wheat flour, oatmeal, whole cornmeal, brown rice and bulgur.
Refined grains have been milled (ground into flour or meal) which results in the bran and germ
being removed. This process removes much of the B-vitamins, iron and dietary fiber. Some
examples of refined grains are wheat flour, enriched bread and white rice.
Most refined grains are enriched, which means that some of the B vitamins and iron are added
back after processing. Fiber, however, is not added back to enriched grains. Some examples
of enriched grains are wheat flour, enriched bread and white rice.
Whole grains health benefits
Eating whole grains provides important health benefits:

Whole grains are generally good sources of dietary fiber; most refined (processed)
grains contain little fiber.

Dietary fiber from whole grains, as part of an overall healthy diet, helps reduce blood
cholesterol levels and may lower risk of heart disease.

Fiber-containing foods such as whole grains help provide a feeling of fullness with fewer
calories and so may help with weight management.
Grains are also important sources of many nutrients:

B vitamins (thiamin, riboflavin, niacin and folate) play a key role in metabolism.

Folate (folic acid), one of the B vitamins, helps the body form red blood cells.

Iron is used to carry oxygen in the blood.

Magnesium is a mineral used in building bones and releasing energy from muscles.

Selenium is important for a healthy immune system.
It’s important to include a variety of grains in your eating plan because grains differ in their
nutrient content. Whole grains can be a good source of fiber, but refined grains usually are not.
Understanding whole grain products
Whole grains are consumed in the United States either as a single food (e.g., wild rice, popcorn)
or as an ingredient in a multi-ingredient food (e.g., in multi-grain breads).
Whole grains cannot be identified by the color of the food. Bread, for example, can be brown
because of molasses or other ingredients, not necessarily because it contains whole grains.
That’s why it’s important to read the ingredient list on the food label. For many whole-grain
products, you will see the words “whole” or “whole grain” before the grain’s name in the
ingredient list. The whole grain should be the first ingredient listed.
Choose foods that contain one of the following ingredients first on the label’s ingredient list:
whole wheat, graham flour, oatmeal, whole oats, brown rice, wild rice, whole-grain corn,
popcorn, whole-grain barley, whole-wheat bulgur and whole rye. These are all whole grains.
When grocery shopping, an easy way to identify whole-grain products is to look for the
American Heart Association Whole Grain heart-check mark on food labels.
This mark on a food label means that it:

Contains 51 percent or more whole grains by weight

Plus is low in saturated fat and cholesterol
Dietary fiber
Dietary fiber is the term for several materials that make up the parts of plants your body can’t
digest. Fiber is classified as soluble or insoluble.
When eaten regularly as part of a diet low in saturated fat, trans fat and cholesterol, soluble
fiber has been associated with increased diet quality and decreased risk of cardiovascular
disease. Soluble or viscous fibers modestly reduce LDL (“bad”) cholesterol beyond levels
achieved by a diet low in saturated and trans fats and cholesterol alone. Oats have the highest
proportion of soluble fiber of any grain. Foods high in soluble fiber include oat bran, oatmeal,
beans, peas, rice bran, barley, citrus fruits, strawberries and apple pulp.
Insoluble fiber can help to prevent constipation: As an indigestible material, insoluble fiber sits
in the gastrointestinal tract, absorbing fluid and sticking to other byproducts of digestion that
are ready to be formed into the stool. Its presence speeds up the movement and processing of
waste, helping prevent gastrointestinal blockage and constipation or reduced bowel
movements. It can also help lowering the risk of diverticular disease: By preventing
constipation and intestinal blockages, insoluble fiber helps reduce the risk of developing small
folds and hemorrhoids in the colon. It may also reduce the risk of colorectal cancer.
Dietary fiber can make you feel full, so you may eat fewer calories. Foods high in insoluble fiber
include whole-wheat breads, wheat cereals, wheat bran, rye, rice, barley, most other grains,
cabbage, beets, carrots, Brussels sprouts, turnips, cauliflower and apple skin.
Many commercial oat bran and wheat bran products (muffins, chips, waffles) contain very little
bran. They also may be high in sodium, total fat and saturated fat. Read labels carefully.
Whole grains daily servings
The number of servings of grains that you need each day depends upon your age, gender and
calorie needs. The recommended amount of grains that a particular person should consume
daily is expressed in terms of “ounce-equivalents” but is commonly referred to as “ounces” (or
servings) of grains.
A person who needs 2,000 calories each day to maintain a healthy body weight could eat 6 to 8
servings of grains (at least half of the servings should be whole-grain foods) and 8 to 10
servings total of vegetables and fruits (about ½ cup counts as a serving).
We recommend obtaining fiber from foods rather than from fiber supplements. Check
the Nutrition Facts label on food packages to find foods with a higher amount of fiber. Try to
get about 25 grams of fiber each day.
Whole and enriched grain choices
The following count as 1 ounce-equivalent (or 1 serving) of grains:
Whole-grain choices

1 slice whole-grain bread (such as 100% whole-wheat bread)

1 ounce ready-to-eat, whole-grain cereal (about 1 cup wheat flakes)

1⁄2 cup cooked whole-grain cereal, brown rice, or whole-wheat pasta

5 whole-grain crackers

3 cups popped popcorn
Enriched choices

1 slice white bread

1 small white roll

1 ounce ready-to-eat cereal (about 1 cup corn flakes)

1⁄2 cup cooked cereal, white rice, or pasta

9 mini 3-ring pretzels

1 4.5 -inch pancake

1 6-inch flour or corn tortilla