Amino acids are the building blocks of protein. The body breaks
down the protein you eat into amino acids and then combines them to form
new proteins that are essential to maintaining and repairing the body.
Meat, poultry, fish and dairy products are considered the best protein
sources, but recent studies suggest that eating a good variety of
plant-based protein throughout the day can provide all of the essential
amino acids that the body needs. Good sources of plant-based protein
include beans and peas, as well as grains, nuts and tofu.
Foods that have been shown to help control inflammation, which is
the body's way of reacting to injury or infection, are called
anti-inflammatory foods. Inflammation is also associated with chronic
conditions such as rheumatoid arthritis, heart disease and lung disease.
Colorful fruits and vegetables – including blueberries, raisins,
spinach, broccoli and beets – are considered anti-inflammatory because
they contain high levels of antioxidants. Anti-inflammatory foods also
include such spices as ginger, rosemary, turmeric, oregano, cayenne,
clove and nutmeg, as well as such herbs as boswellia, willow bark and
Antioxidants are substances believed to protect the body's cells
against the oxidative damage caused by free radicals, which are
molecules produced when the body breaks down food or when you are
exposed to harmful things like radiation or tobacco smoke. A good
example of oxidative damage is the way an apple's flesh turns brown once
it's been sliced. Fruits and vegetables are rich in antioxidant
nutrients, including beta carotene, lutein, lycopene, selenium and
vitamins A, C and E. Dip that apple slice in vitamin C-rich orange
juice, and it will stay white.
B vitamins are a series of water-soluble vitamins essential to
human growth and development because they help the body break down food
into energy and then use that energy properly. They also help in the
production of red blood cells, hormones and DNA, and in maintaining the
health of vital body functions performed by the immune system and the
nervous system. B vitamins are thiamine (B1), riboflavin (B2), niacin
(B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folic acid,
also called folate (B9), and cobalamin (B12). The food sources of B
vitamins include an array of fruits and vegetables, depending on the
particular vitamin in question. [See Vitamins below.]
A natural pigment formed by plants, beta carotene is a known
antioxidant and stimulant for the immune system. The body also can
convert beta carotene into vitamin A if needed. Beta carotene is found
in bright, colorful fruits and vegetables, including carrots, squash,
sweet potatoes, apricots, cantaloupe, papaya, pumpkin, leafy greens and
This dark-red pigment is naturally produced in beets and has strong antioxidant properties.
The most plentiful mineral in the human body is calcium. It plays
a role in bone development, muscle contraction, the expansion and
contraction of blood vessels, hormone and enzyme secretion, and
transmission of impulses through the nervous system. Dairy products are
most people's main source of calcium. But, it is also found in broccoli,
spinach, Chinese cabbage, kale and other dark green, leafy vegetables.
Calories are a way to measure the energy contained in food. One
calorie is the amount of energy required to raise the temperature of 1
gram of water by 1 degree centigrade. Different foods contain different
amounts of calories depending on the fats, carbohydrates and proteins
that they contain. Fruits and vegetables are made up mostly of
carbohydrates and proteins, which contain 4 calories per gram. Animal
products often contain high amounts of fat, which contain 9 calories per
gram. When most people think of calories, they think of weight: Eat
foods with more calories, gain weight; take in fewer calories, lose
Carbohydrates are one of the three main components of foods,
along with protein and fat. They come in several forms, such as sugars,
fibers and starches. Carbohydrates (or carbs, for short) are broken down
by the body into glucose, which can be stored or used as fuel for cells
and tissues. One gram of carbohydrate contains 4 calories.
is important to limit your simple carbohydrate intake from refined
grains like white rice or white bread and from sugars like sodas and
sweets. You should eat more complex carbohydrates. Complex
carbohydrates contain more fiber and other beneficial nutrients that may
help control blood glucose levels and may help decrease the risk of
heart disease. These are found naturally in fruits, vegetables and
whole grains like oatmeal, brown rice and whole wheat pasta.
healthy sources of carbohydrates include apples, pears, peaches,
blackberries, cherries and strawberries, as well as yams, peas, beans
and, especially, whole grains.
Chloride is a salt that is used to help keep body fluids properly
in balance. It is also an essential component of digestive juices.
People get most of their chloride from table salt (sodium chloride).
However, certain vegetables – including tomatoes, lettuce and celery –
and olives also contain high amounts of chloride.
Cholesterol is a waxy, fat-like substance that occurs naturally
in the body. Though improper amounts can cause problems, cholesterol is
essential for the body to function properly. It helps make up cell
walls and membranes throughout the body, including in the brain, nerves,
muscle, skin, heart, liver and intestines. The body also uses
cholesterol to produce a number of hormones, create vitamin D and
concoct the bile acids needed to digest fat.
The problem is that
only a small amount of cholesterol is needed in the bloodstream to meet
these demands. If you take in too much cholesterol through your diet, it
can begin to stick to the sides of your artery walls and harden into
what are called plaques. These can block blood flow, lead to heart
disease and increase your chances of having a heart attack or stroke.
comes in two basic types: low-density lipoprotein (LDL) cholesterol,
the bad type; and high-density lipoprotein (HDL) cholesterol, the good
kind. LDL cholesterol is bad because it's the type that forms artery
plaques when levels are too high. The body creates all the LDL
cholesterol you need, so any amount that's ingested is too much. LDL
enters the diet in the form of saturated fats or trans fats.
cholesterol is considered good because it actually helps lower your
overall cholesterol levels by clearing bad cholesterol from the
bloodstream. HDL cholesterol is ingested in the form of monounsaturated
and polyunsaturated fats.
Most fruits and vegetables do not
contain cholesterol. However, some plant-based foods – including nuts,
seeds and avocados – do contain good HDL cholesterol.
The mineral copper is present in all body tissues. It is used to
form red blood cells. Copper also helps keep bones strong and the
circulatory, nervous and immune systems healthy. The best source of
dietary copper is shellfish, including oysters, clams, lobsters and
crabs. However, dark green, leafy vegetables and dried fruits (such as
prunes and raisins) also contain copper, as do beans, potatoes, whole
grains, nuts, cocoa, black pepper and yeast.
"Daily Value" is a phrase that is part of the Nutrition Facts
labeling that's required on nearly all food products in the United
States. The information lets you determine the amount of key nutrients
that are contained in a food product. For example, it might indicate
that a certain food has 10 percent of the recommended amount of
carbohydrates that you should consume in a day. That means that one
serving provides 10 percent of the recommended daily allowance of
carbohydrate. The percentages shown on package labels are based on a
diet of 2,000 calories a day. If your dietary needs are different, you
may need to do some math.
Dietary fiber – insoluble
Insoluble dietary fiber does not dissolve in water. It helps move
material through the digestive system and promotes stool bulk, making
this type of dietary fiber important for people who have constipation or
irregular bowel movements. Insoluble fiber can be found in green
beans, the skins of such fruits as apples and pears, the skins of root
vegetables such as potatoes and yams, whole-wheat flour, bran from wheat
or corn, seeds, nuts, and dark green, leafy vegetables.
Dietary fiber – soluble
Soluble dietary fiber dissolves in water, forming a gel-like
substance. The gel prolongs the time it takes for the stomach to empty,
which slows the release of sugar into the bloodstream and keeps blood
glucose levels steady, reducing your risk for diabetes. Soluble dietary
fiber also binds with fats, lowering your blood cholesterol levels.
Soluble fiber comes from fruits such as apples and oranges, and
vegetables such as peas, carrots and beans, as well as from oats, barley
Essential amino acids
Many types of amino acids exist, but some cannot be produced by
the body. It is essential that they be supplied by food. Hence, they're
called essential amino acids. They include arginine, histidine,
isoleucine, leucine, lysine, methionine, phenylalanine, threonine,
tryptophan and valine. If you don't get these amino acids in your diet,
muscle and other protein-based parts of your body will begin to waste
away. Essential amino acids can be found in high-protein animal foods,
such as milk, cheese, eggs and meats. However, there are some
plant-based sources as well, including beans, peas, soy, nuts and seeds.
[See also: Amino acids]
Fat is one of the three main components of food (together with
carbohydrates and protein). Fat is a major source of energy for the
body, containing twice as many calories per gram as either carbohydrates
or proteins. It also helps form the walls of every cell in the body and
is an essential building block in the brain and nervous system. Fat
also helps the body make hormones and absorb vitamins. However, because
fat is so high in calories, eating too much can lead to weight problems.
Fat comes in two naturally occurring forms: saturated and unsaturated
fat. There also is a man-made form of dietary fat, known as trans fat.
Fat – Saturated fat
Saturated fat is the main cause of high levels of the bad LDL
cholesterol. It is found mainly in meats, chicken with skin and
whole-milk dairy products. But, it also is present in coconut, palm and
palm kernel oils. Experts recommend that people limit their intake of
saturated fat to 10 percent of their daily calories.
Fat – Trans fat
Trans fat is man-made, formed through a process called
hydrogenation that involves heating liquid vegetable oils in the
presence of hydrogen gas. This causes the liquid oil to become solid and
very stable, which allows products to have a long shelf life. However,
trans fats are incredibly bad for you. Not only do they increase the
levels of LDL cholesterol (the bad kind) in your blood, but they also
decrease the levels of the good HDL cholesterol. No amount of trans fat
is good for you to consume.
Fat – Unsaturated fat
Unsaturated fat comes in two forms, monounsaturated and
polyunsaturated. Unsaturated fats are found mainly in fish, nuts, seeds,
avocados and olives. They also can be found in liquid vegetable oils
made from soybeans, corn, safflowers, canola, olives and sunflowers.
Unsaturated fats increase the levels of HDL cholesterol (the good type)
in the body and should be your main source of dietary fat.
Fiber is a form of carbohydrate that the body cannot digest. It
is present in the cell walls of all plants eaten as food, including
fruits, vegetables and grains. Fiber is very important in the digestive
process and can prevent constipation. Research has also linked
high-fiber diets to reduced incidence of heart disease, diabetes and
diverticulitis. It is recommended that adults eat at least 25 grams of
fiber a day. There are two forms of dietary fiber, soluble and
insoluble; both have health benefits.
Flavonoids are antioxidant chemicals found in plants, where they
help repair damage and provide protection from environmental toxins.
Research has found that foods rich in flavonoids may help reduce a
person's chance of heart disease. There are more than 4,000 flavonoid
compounds, found in a wide variety of foods and beverages. These include
citrus fruit, grapes, berries, apples, parsley, thyme, celery, hot
peppers, broccoli, soybeans, peanuts, chocolate, onions, tea and red
Folate is a B-complex vitamin also known as vitamin B9 and folic
acid. It works with vitamin B12 and vitamin C to help the body break
down proteins into amino acids and then recombine them into new
proteins. Folate helps the body form red blood cells and produce DNA,
and it also helps tissues and cells grow and work. Women are encouraged
to take folate before and during pregnancy to prevent birth defects such
as spina bifida. Folate can be found in citrus fruits (such as oranges
and grapefruit), as well as in citrus juices, beans, whole grains and
dark green, leafy vegetables.
Free radicals are molecules produced when the body breaks down
food or is exposed to something harmful, such as radiation or tobacco
smoke. The molecules contain oxygen and are highly chemically reactive,
and they can damage human cells and tissues. Free radicals are suspected
to be a cancer cause by disrupting DNA, and they also are suspected to
be a factor in diseases associated with aging. Antioxidants, which are
plentiful in fruits and vegetables, can limit free radical damage.
Gluten (and Gluten-free)
Gluten is a protein found in wheat, rye and barley. Gluten helps
form flour into dough and gives kneaded dough its elasticity, allows
leavening in dough or batter and provides chewiness to baked products
such as bagels and breads.
People who have celiac disease, an
intestinal disorder, are intolerant of gluten. Consuming gluten causes
their immune system to attack the digestive system, producing bloating,
pain, diarrhea, constipation, nausea and weight loss. The only treatment
for celiac disease is to go on a gluten-free diet. This diet focuses on
consumption of meats, fish, poultry, fruits and vegetables – none of
which contain gluten. It also calls for substituting wheat flour in
baked goods and pastas with flours made from potatoes, rice, soy,
amaranth, quinoa, buckwheat or beans.
High-fructose corn syrup
High fructose corn syrup (HFCS) is a sweetener made from corn and
can be found in numerous foods and beverages on grocery store shelves
in the United States. High fructose corn syrup is composed of either 42
percent or 55 percent fructose, with the remaining sugars being
primarily glucose and higher sugars. In terms of composition, high
fructose corn syrup is nearly identical to table sugar. The American
Medical Association stated in June 2008 that “…high fructose syrup does
not appear to contribute to obesity more than other caloric sweeteners…”
And, the American Dietetic Association (ADA) concluded in December 2008
that “No persuasive evidence supports the claim that high fructose corn
syrup is a unique contributor to obesity.” The ADA also noted, “High
fructose corn syrup … is nutritionally equivalent to sucrose. Both
sweeteners contain the same number of calories (4 per gram) and consist
of about equal parts of fructose and glucose. Once absorbed into the
blood stream, the two sweeteners are indistinguishable.”
Insulin, which is a hormone produced by the pancreas, helps the
body's cells take in glucose (sugar) and convert it to energy. Sometimes
this process goes awry, and the result is diabetes. A person's body
might stop producing insulin or might become resistant to it (meaning
the body cannot use it properly), requiring more of the hormone to
process blood sugar and bring blood glucose levels back to normal.
Iodine, an essential element for human health, is necessary for
cells to convert food into energy. It also is required for normal
thyroid gland functioning and for the production of thyroid hormones.
Table salt with iodine added, often called iodized salt, is the main
food source of iodine for most people, but seafood and dairy products
also contain it. Plant sources of iodine include kelp and any vegetables
grown in iodine-rich soil.
Iron is an essential mineral for human health because it is
needed to create blood cells. The body needs iron to create hemoglobin
and myoglobin, proteins that carry oxygen to cells and muscles.
Too-little iron can lead to anemia. The best sources of iron are
animal-based foods such as meat, poultry, fish and eggs. Whole grains,
though, are another source of iron. Though iron is not as plentiful in
fruits and vegetables, it can be found in dried fruits such as prunes
and raisins, and in such vegetables as broccoli, spinach, kale, collard
greens and asparagus. Nuts, seeds and beans also contain iron.
Lutein is an antioxidant and a pigment that is plentiful in dark
green, leafy vegetables, including spinach, kale, collard greens and
broccoli. It is also found in green beans, peas and corn. Research has
suggested that lutein may lower a person's chances of developing such
eye disorders as cataracts and macular degeneration.
Lycopene is a red pigment that provides color to tomatoes, pink
grapefruit, apricots, red oranges, watermelon, rose hips and guava.
Because of its strong antioxidant properties, lycopene is believed to
help retard the aging process and stave off heart disease, cancer and
major degenerative diseases. Some research has found that cooking foods
containing lycopene – tomatoes, for instance – makes the lycopene more
easily absorbed by the body. That would make canned tomatoes one of the
better sources of lycopene.
The mineral magnesium is found in abundance in the body, with
about half residing in bone and the rest in body tissues and major
organs. Magnesium contributes to the makeup of teeth and bones and also
plays a key role in more than 300 biochemical reactions in the body.
Magnesium helps maintain normal muscle and nerve function, keeps the
heart's rhythm steady, supports a healthy immune system, aids the
regulation of blood sugar levels and promotes normal blood pressure.
Research has focused on the potential of magnesium to prevent or treat
hypertension, cardiovascular disease and diabetes. Green vegetables such
as spinach, peas and green beans are good sources of magnesium because
the green pigment chlorophyll contains the mineral. Legumes, tofu, nuts
and unpeeled potatoes also contain magnesium.
Manganese is considered a trace mineral, which means the body
needs only tiny amounts of it. In the body, it resides mostly in bones
and such organs as the liver, kidneys and pancreas. Manganese helps form
connective tissue, develop and repair bone, clot blood, produce sex
hormones, process fats and carbohydrates, absorb calcium and regulate
blood sugar. Manganese also is a component of the antioxidant enzyme
superoxide dismutase. Fruits and vegetables rich in manganese include
pineapple, raspberries and leafy greens, including mustard greens, kale,
chard, romaine lettuce and collard greens. Whole grains, nuts, seeds,
teas and maple syrup also contain high levels of manganese.
Niacin (or vitamin B3) is found in high-protein foods, including
nuts, peanut butter, beef, poultry and fish, as well as broccoli,
carrots and beets. Niacin helps convert carbohydrates into energy and
also helps the body create hormones in the adrenal gland and other parts
of the body.
Preservatives are substances added to foods to help keep them
fresh. Some preservatives are antimicrobials, which keep bacteria,
molds, fungi or yeast from spoiling foods. Others are antioxidants,
which slow or prevent foods from turning rancid or changing in color,
flavor or texture. Preservatives are used in fruit sauces and jellies,
cereals, dressings, beverages, baked goods, cured meats, oils and
margarines, snack foods, fruits and vegetables. Some examples include
ascorbic acid, citric acid, sodium benzoate, calcium propionate, sodium
erythorbate, sodium nitrite, calcium sorbate and potassium sorbate.
Food additives that impart sweetness to processed foods are known
as artificial sweeteners. Most artificial sweeteners are low-calorie or
calorie-free and are used in diet foods and beverages, replacing
higher-calorie sugar. They include saccharin, aspartame, sucralose,
acesulfame potassium (acesulfame-K) and neotame. There have been health
concerns raised regarding artificial sweeteners, such as fears that they
may cause cancer, but research has not supported such concerns and
generally has found them safe for most people. People with PKU (a rare
hereditary disease known as phenylketonuria), however, should not use
Omega-3s is the shorthand name for omega-3 fatty acids, which are
considered essential to human health but are not produced by the body
and must be obtained through food. Major sources of omega-3s include
oily fish such as salmon, mackerel and lake trout, as well as nuts,
seeds and some vegetable oils. Omega-3 fatty acids have been linked to
numerous health benefits, including reduced risk for heart disease,
cancer and arthritis. Omega-3s also are highly concentrated in the brain
and appear to serve an important role in cognition. They also
contribute to healthy skin and hair.
Organic food products are those grown without the use of
synthetic substances, including chemical fertilizers, pesticides and
herbicides. Bioengineering and ionizing radiation also cannot be part of
the growing process, according to standards set by the U.S. Department
of Agriculture. Organic animal products (meat, poultry, eggs and dairy
products) come from animals that were raised on organic feed, given no
antibiotics or growth hormones and were raised outdoors. A product
labeled as "organic" has been certified as such by a government
inspector who visited the farm where the food originated. [Also see USDA
Other descriptions – including that a food is natural,
free-range or hormone-free – are not synonymous with organic. A food
designated as "organic" has met certain growing and production standards
that differ from conventional methods. Organic foods, however, are not
necessarily safer or more nutritious than other foods.
Pectin is a soluble fiber that's found concentrated in apples and
in the peel and pulp of citrus fruits. It is used as a gelling agent in
food to help make jams, jellies and preserves. Pectin also is used as a
remedy for diarrhea and as a means to lower blood cholesterol. Research
has indicated that pectin may provide some protection against colon and
The mineral phosphorus is found throughout the body, particularly
in the bones and teeth. It makes up about 1 percent of an average
person's weight. The body mainly uses phosphorus to help build bones and
teeth, but the mineral also plays an important role in the breakdown of
carbohydrates and fats for energy and in the creation of new proteins
to help maintain and repair cells and human tissues. Phosphorus also
helps muscles contract and aids in keeping the kidneys, heart and nerves
functioning normally. The main dietary sources of phosphorus are
high-protein animal foods such as meat and milk.
Phytochemicals are compounds that occur naturally in plants,
including fruits and vegetables. Thousands of phytochemicals have been
identified by scientists, including antioxidants, flavonoids,
carotenoids and polyphenols, all of which offer health benefits for
human beings. Some evidence exists that a diet rich in foods containing
phytochemicals may stave off some diseases and cancers. Taking
phytochemical supplements, however, has not been shown to be as
beneficial as eating the fruits, vegetables and grains that contain
Polyphenols are a type of phytochemical that provides red, blue
and purple pigmentation to plants. Polyphenols have strong antioxidant
properties and have been linked to decreased risk for cancer and
cardiovascular disease. Polyphenols are found in citrus fruits, berries,
apples, pears, onions, tomatoes, legumes, green tea, red wine and herbs
such as dill, parsley, oregano and thyme.
The mineral potassium is essential for electrical conduction in
the body, including the normal electrical activity of the heart. It also
is used to build muscle by aiding in the creation of new proteins from
amino acids. Vegetable sources of potassium include broccoli, tomatoes,
lima beans, peas, winter squashes and sweet potatoes. Fruits with high
levels of potassium include citrus fruits, bananas, cantaloupe, prunes,
apricots and kiwi. Potassium also can be found in meats, fish, soy and
Protein is one of the three main components of foods, along with
carbohydrates and fat. Proteins contain half the calories of fats and
tend to break down over a longer period of time than carbohydrates.
That's why eating protein leaves you feeling full longer. In the body,
protein is found in every cell. It is essential for providing the amino
acids that the body needs to repair cells and build new muscle, bone
The proteins most useful to human health are contained in
animal products such as meat, fish and dairy. Proteins in fruits and
vegetables are considered “incomplete,” in that they must be combined
with other protein sources to provide all the amino acids needed for
health. However, protein from animal sources (think steak) often comes
with considerable fat as well, whereas plant-based sources of protein
(lentils, perhaps) have little if any fat. Because the body doesn't
store protein, it needs to be part of your daily diet. Plant-based
sources of protein include beans, nuts and whole grains.
People who have high blood pressure often are encouraged to go on
a low-salt or salt-free diet. They must either eliminate sodium (salt)
completely from their diet or restrict its consumption to less than
2,000 milligrams a day. Such diets often place an emphasis on
consumption of fruits and vegetables because they are naturally low in
Selenium is a trace mineral, meaning the body needs only a small
amount of it. It gets combined with proteins in the body to create
selenoproteins, which are important antioxidant enzymes that protect
against cell damage, help regulate thyroid function and keep the immune
system working properly. Selenium also can improve sperm production and
motility. Vegetables are a primary food source of selenium. The plants
get their selenium from the earth, so the amount of selenium in a
particular vegetable will depend on how much of the mineral was in the
soil where that vegetable was grown. Fish, meats, grains and eggs are
also good sources of the mineral.
Sodium is an element used by the body to regulate blood pressure,
aid in muscle and nerve function and keep the right balance of fluids
in the body. However, too much sodium can cause high blood pressure,
which is a major risk factor for heart disease and stroke. Most dietary
sodium comes in the form of table salt. Celery and cheese are high in
sodium. Sodium also is part of many food additives and preservatives,
including monosodium glutamate, sodium nitrite, sodium saccharin and
baking soda. An estimated 90 percent of Americans take in more sodium
each day than their body needs. Premade meals, soups, and processed
meats like hotdogs and lunchmeat are often high in sodium.
The U.S. Department of Agriculture has established a labeling
system to help consumers accurately select organic meats and produce.
Products labeled “USDA Organic” must be either produced 100 percent with
organic ingredients and processing aids or be at least 95 percent
organic ingredients, and include only minimal amounts of non-organic
substances that are USDA-approved but not commercially available in
organic form. A product labeled as "organic" has been certified as such
by a government inspector who visited the farm where the food
originated. The shipping and handling of the food product also has been
Organic food products are those grown without the use
of synthetic substances, including chemical fertilizers, pesticides and
herbicides and without bioengineering or ionizing radiation, according
to USDA standards. Organic animal products (meat, poultry, eggs and
dairy products) come from animals that were raised on organic feed,
given no antibiotics or growth hormones and were raised outdoors.
organic foods will bear a brown-and-green USDA seal (or the seal will
be on the bin where they are displayed in the market), identifying them
as "100 percent organic" or simply "organic" (95 percent or more organic
ingredients). Other common labeling terms, which would not carry the
USDA seal, include "made with organic ingredients" (at least 70 percent
organic) or "less than 70 percent organic ingredients" (with details
given on the label). [See also Organic.]
Vegetarian diets focus on plants as the source for food. In
addition to vegetables, common ingredients in vegetarian recipes are
fruits, grains, seeds and nuts. However, some vegetarians also will
include dairy products (a lacto vegetarian diet) in their recipes, or
they will include dairy products, eggs, milk and honey (referred to as
lacto-ovo). Vegan recipes are the strictest, excluding all meat and
Vitamin A is a fat-soluble vitamin that's also known as retinol
because it produces the pigments found in the retina of the eye. Vitamin
A promotes good vision and also helps the body build and maintain
healthy teeth, bones, soft tissue, mucous membranes and skin. Eggs,
dairy products, meat and liver are good sources of vitamin A. You also
can get vitamin A from carotenoids such as beta carotene, a naturally
occurring pigment found in plant foods that can be processed by the body
into a form of vitamin A. Carotenoids can be found in carrots, pumpkin,
sweet potatoes, winter squashes, cantaloupe, pink grapefruit, apricots,
broccoli and spinach.
Vitamin B1 (Thiamine)
A B-complex vitamin, thiamine helps the body convert
carbohydrates into energy. It also is involved in the function of the
heart, muscles and nervous system. Thiamine is found in vegetables such
as dried beans, peas and soybeans, as well as in whole grains, lean
meats and fish.
A B-complex vitamin essential for the body's proper growth and
development, B12 also plays a part in the function of the nervous system
and production of red blood cells. There are no significant plant-based
sources of vitamin B12; rather, it can be found in eggs, meat, poultry,
shellfish and dairy products.
Vitamin B2 (Riboflavin)
Vitamin B2 helps the body break down carbohydrates, fats and
proteins into fuel for cells. It also is needed to properly use other B
vitamins, such as niacin, folate and vitamin B6. Riboflavin is found in
broccoli, Brussels sprouts, mushrooms, asparagus, spinach and other dark
green, leafy vegetables.
Vitamin B3 (Niacin)
Vitamin B3 is found in high-protein foods, including nuts, peanut
butter, beef, poultry and fish, as well as broccoli, carrots and beets.
Niacin helps convert carbohydrates into energy and also helps the body
create hormones in the adrenal gland and other parts of the body.
Also known as pantothenic acid, vitamin B5 influences normal
human growth and development. It is found in nearly all foods, but rich
sources of B5 include broccoli, egg yolk, liver, kidney, mushrooms,
avocado and sweet potatoes.
A B-complex vitamin, B6 is also known as pyridoxine. It helps
create hemoglobin, the substance within red blood cells that carries
oxygen to the body's tissues. Vitamin B6 also can increase the amount of
oxygen that hemoglobin is able to transport. B6 is important to the
immune and nervous systems and helps regulate blood glucose levels.
Plant-based sources of this vitamin include potatoes, bananas, dried
beans, avocado and whole grains.
Also known as ascorbic acid, vitamin C is essential to healing
wounds and repairing body tissues. It is used to form collagen, an
important protein that helps form skin, scar tissue, tendons, ligaments
and blood vessels. It helps the body absorb iron, and it plays a role in
controlling infections. Vitamin C also is an antioxidant. As such, it
helps shield the body's cells from damage caused by free radicals, which
are molecules produced when the body breaks down food or when you are
exposed to harmful things like radiation or tobacco smoke. All fruits
and vegetables contain some vitamin C, but the best sources are citrus
fruits, tomatoes, green peppers, strawberries, broccoli and dark, leafy
greens. Other good sources include red peppers, berries, pineapple,
papaya, mango, watermelon, Brussels sprouts, cauliflower, cabbage and
Vitamin D is needed for strong bones. It is stored in the body's
fatty tissues and helps with the absorption of calcium. The body
manufactures vitamin D when it is exposed to sunlight (hence its
nickname as the "sunshine vitamin). About 15 minutes of sunshine three
times a week is enough to produce the required amount. However, many
people – especially those living in northern climates, as well as people
who are overweight – do not get enough vitamin D naturally.
Researchers now believe that vitamin D deficiency not only makes soft or
brittle bones and osteoporosis more likely, but also increases the risk
for heart disease and some cancers as well as infectious diseases,
including seasonal flu and tuberculosis. Though Vitamin D is found in
dairy products and fish, few foods contain naturally high levels of
vitamin D. However, it is often added to foods (which will be labeled as
vitamin D fortified).
A fat-soluble vitamin, vitamin E serves mainly as an antioxidant,
but it also helps the body form red blood cells and use vitamin K.
Vegetable sources of vitamin E include spinach, olives, corn, asparagus
and other green leafy vegetables. It's also found in wheat germ, nuts,
seeds and vegetable oils.
Vitamin K is known as the clotting vitamin. Without it, blood
would not be able to clot. Some research also has found that it may help
older people maintain strong bones. It is found in many foods,
especially in green leafy vegetables such as broccoli, collard greens,
Brussels sprouts and spinach, as well as cabbage, cauliflower and
soybeans. Vitamin K is also produced by bacteria in the gastrointestinal
The phrase "whole grain" refers to all three parts of a kernel of
grain: the bran, the germ and the endosperm. The bran is the hard outer
layer of the grain (which provides fiber), the germ is the seed
(providing protein) and the endosperm is the tissue that surrounds and
nourishes the seed (providing carbohydrate). When grains are refined
into white flour, the bran and germ are milled away, leaving only the
endosperm. This gives the flour a finer texture and improves its shelf
life, but the processing also robs it of nutrients such as fiber, iron
and B-complex vitamins. Whole-grain flours and foods, which contain all
three parts of the grain kernel, are more nutritious and also keep blood
glucose levels more stable because they take longer to digest.
The mineral zinc has the second-highest level of concentration in
the human body, after iron. The immune system relies on zinc to work
properly, and it also aids in cell division, cell growth and wound
healing. Zinc also helps break down carbohydrates and is necessary for
the senses of smell and taste. High-protein foods – including beans,
peanuts and meat – also have high levels of zinc. Most fruits and
vegetables are not good sources of zinc because the zinc in plant
proteins cannot be utilized by the human body.