Fat

Definition

Fats are organic compounds that are made up of carbon, hydrogen, and oxygen. They are a source of energy in foods. Fats belong to a group of substances called lipids, and come in liquid or solid form. All fats are combinations of saturated and unsaturated fatty acids.

Overview & Functions

Fat is one of the 3 nutrients (along with protein and carbohydrates) that supply calories to the body. Fat provides 9 calories per gram, more than twice the number provided by carbohydrates or protein.
Fat is essential for the proper functioning of the body. Fats provide essential fatty acids, which are not made by the body and must be obtained from food. The essential fatty acids are linoleic and linolenic acid. They are important for controlling inflammation, blood clotting, and brain
development.

Fat serves as the storage substance for the body's extra calories. It fills the fat cells (adipose tissue) that help insulate the body. Fats are also an important energy source. When the body has used up the calories from carbohydrates, which occurs after the first 20 minutes of exercise, it begins to depend on the calories from fat.
Healthy skin and hair are maintained by fat. Fat helps the body absorb and move the vitamins A, D, E, and K through the bloodstream.

Food Sources

SATURATED FATS
These are the biggest dietary cause of high LDL levels ("bad cholesterol"). When looking at a food label, pay very close attention to the percentage of saturated fat and avoid or limit any foods that are high. Saturated fat should be limited to 10% of calories. Saturated fats are found in animal products such as butter, cheese, whole milk, ice cream, cream, and fatty meats. They are also found in some vegetable oils -- coconut, palm, and palm kernel oils. (Note: Most other vegetable oils contain unsaturated fat and are healthy.)


UNSATURATED FATS
Fats that help to lower blood cholesterol if used in place of saturated fats. However, unsaturated fats have a lot of calories, so you still need to limit them. Most (but not all) liquid vegetable oils are unsaturated. (The exceptions include coconut, palm, and palm kernel oils.) There are two types of unsaturated fats:

• Monounsaturated fats: Examples include olive and canola oils.
• Polyunsaturated fats: Examples include fish, safflower, sunflower, corn, and soybean oils.

TRANS FATTY ACIDS
These fats form when vegetable oil hardens (a process called hydrogenation) and can raise LDL levels. They can also lower HDL levels ("good cholesterol"). Trans fatty acids are found in fried foods, commercial baked goods (donuts, cookies, crackers), processed foods, and margarines.
HYDROGENATED AND PARTIALLY HYDROGENATED FATS
This refers to oils that have become hardened (such as hard butter and margarine). Partially hydrogenated means the oils are only partly hardened. Foods made with hydrogenated oils should be avoided because they contain high levels of trans fatty acids, which are linked to heart disease. (Look at the ingredients in the food label.)

Recommendations

• Choose lean, protein-rich foods such as soy, fish, skinless chicken, very lean meat, and fat-free or 1% dairy products.
• Eat foods that are naturally low in fat such as whole grains, fruits, and vegetables.
• Get plenty of soluble fiber such as oats, bran, dry peas, beans, cereal, and rice.
• Limit fried foods, processed foods, and commercially prepared baked goods (donuts, cookies, crackers).
• Limit animal products such as egg yolks, cheeses, whole milk, cream, ice cream, and fatty meats (and large portions of meats).
• Look at food labels, especially the level of saturated fat. Avoid or limit foods high in saturated fat.
• Look on food labels for words like "hydrogenated" or "partially hydrogenated" -- these foods are loaded with bad fats and should be avoided.
• Liquid vegetable oil, soft margarine, and trans fatty acid-free margarine are preferable to butter, stick margarine, or shortening.

Children under age 2 should NOT be on a fat-restricted diet because cholesterol and fat are thought to be important nutrients for brain development.
It is important to read the nutrition labels and be aware of the amount of different types of fat contained in food. If you are 20, ask your health care provider about checking your cholesterol levels.

Side Effects

Eating too much saturated fat is one of the major risk factors for heart disease. A diet high in saturated fat causes a soft, waxy substance called cholesterol to build up in the arteries. Too much fat also increases the risk of heart disease because of its high calorie content, which increases the chance of becoming obese (another risk factor for heart disease and some types of cancer).
 A large intake of polyunsaturated fat may increase the risk for some types of cancer. Reducing daily fat intake is not a guarantee against developing cancer or heart disease, but it does help reduce the risk factors.

Omega-3 fatty acids 

Omega-3 fatty acids are a form of polyunsaturated fat that the body derives from food. Omega-3s (and omega-6s) are known as essential fatty acids (EFAs) because they are important for good health. The body cannot make these fatty acids on its own so omega-3s must be obtained from food. These different types of acids can be obtained in foods such as cold-water fish including tuna, salmon, and mackerel. Other important omega 3 fatty acids are found in dark green leafy vegetables, flaxseed oils, and certain vegetable oils.
Omega-3 fatty acids have been found to be beneficial for the heart. Positive effects include anti-inflammatory and anti-blood clotting actions, lowering cholesterol and triglyceride levels, and reducing blood pressure. These fatty acids may also reduce the risks and symptoms for other disorders including diabetes, stroke, rheumatoid arthritis, asthma, inflammatory bowel disease, ulcerative colitis, some cancers, and mental decline.
 

Fiber

Definition

Fiber is a substance found in plants. Dietary fiber -- the kind you eat -- is found in fruits, vegetables, and grains. It is an important part of a healthy diet.

Overview & Functions

Dietary fiber adds bulk to your diet. Because it makes you feel full faster, it can be helpful in controlling weight. Fiber aids digestion, helps prevent constipation, and is sometimes used for the  treatment of diverticulosis, diabetes, and heart disease.

Food Sources

There are two forms of fiber: soluble and insoluble.
Soluble fiber attracts water and turns to gel during digestion. This slows digestion. Soluble fiber is found in oat bran, barley, nuts, seeds, beans, lentils, peas, and some fruits and vegetables. Soluble fiber has been scientifically proven to lower cholesterol, which can help prevent heart disease.

 Insoluble fiber is found in foods such as wheat bran, vegetables, and whole grains. It appears to speed the passage of foods through the stomach and intestines and adds bulk to the stool.

Recommendations

The average American now eats 10 - 15 grams of fiber per day. The recommendation for older children, adolescents, and adults is 20 - 35 grams per day. Younger children will not be able to eat enough calories to achieve this, but it is a good idea to introduce whole grains, fresh fruits, and other high-fiber foods.
To ensure that you get enough fiber, eat a variety of foods, including:

• Cereals
• Dried beans and peas
• Fruits
• Vegetables
• Whole grains

Add fiber gradually over a period of a few weeks to avoid abdominal discomfort. Water aids the passage of fiber through the digestive system. Drink plenty of fluids (approximately 8 glasses of water or non-caloric fluid a day).
Peeling can reduce the amount of fiber in fruits and vegetables. Eating fiber-containing food is beneficial, whether it is cooked or raw.

Side Effects

Eating a large amount of fiber in a short period of time can cause intestinal gas (flatulence), bloating, and abdominal cramps. This usually goes away once the natural bacteria in the digestive system get used to the increase in fiber in the diet. Adding fiber gradually to the diet, instead of all at one time, can help reduce gas or diarrhea.

 Too much fiber may interfere with the absorption of minerals such as iron, zinc, magnesium, and calcium. However, this effect usually does not cause too much concern because high-fiber foods are typically rich in minerals.

Sources of fiber

The addition of fiber in the diet aids in digestion and helps to avoid constipation. Vegetables, fresh fruits (especially dried fruits) and whole wheat, bran, or oatmeal cereals are excellent sources of fiber. To reap the benefits of fiber, it is very important to drink plenty of fluids.




 

Magnesium in diet

Definition

Magnesium is an essential mineral for human nutrition.

Overview & Functions

Magnesium in the body serves several important functions:

• Contraction and relaxation of muscles
• Function of certain enzymes in the body
• Production and transport of energy
• Production of protein

Food Sources

Most dietary magnesium comes from vegetables, such as dark green, leafy vegetables. Other foods that are good sources of magnesium:

• Fruits or vegetables (such as bananas, dried apricots, and avocados)
• Nuts (such as almonds and cashews)
• Peas and beans (legumes), seeds
• Soy products (such as soy flour and tofu)
• Whole grains (such as brown rice and millet)

Recommendations

These are the recommended daily requirements of magnesium:

• Children
  • 1 - 3 years old: 80 milligrams
  • 4 - 8 years old: 130 milligrams
  • 9 - 13 years old: 240 milligrams
  • 14 - 18 years old (boys): 410 milligrams
  • 14 - 18 years old (girls): 360 milligrams
  
  
• Adult females: 310 - 320 milligrams
• Pregnancy: 350 - 400 milligrams
• Breastfeeding women: 310 - 360 milligrams
• Adult males: 400 - 420 milligrams

Side Effects

Side effects from increased magnesium intake are not common because the body removes excess amounts. Magnesium excess almost always occurs only when magnesium is supplemented as a medication. Lack of magnesium (deficiency) is rare. The symptoms include:
• Hyperexcitability
• Muscle weakness
• Sleepiness
Deficiency of magnesium can occur in people who abuse alcohol or in those who absorb less magnesium due to:
• Burns
• Certain medications
• Low blood levels of calcium
• Problems absorbing nutrients from the intestinal tract (malabsorption)
• Surgery
Symptoms due to a lack of magnesium have three categories. Early symptoms:
• Anorexia
• Apathy
• Confusion
• Fatigue
• Insomnia
• Irritability
• Muscle twitching
• Poor memory
• Reduced ability to learn
Moderate deficiency symptoms:
• Heart (cardiovascular) changes
• Rapid heartbeat
Severe deficiency:
• Continued muscle contraction
• Delirium
• Numbness
• Seeing or hearing things that aren't there (hallucinations)
• Tingling

Selenium in diet

Definition

Selenium is an essential trace mineral. Small amounts of selenium are good for your health.

Overview & Functions

Selenium has a variety of functions. It helps make special proteins, called antioxidant enzymes, which play a role in preventing cell damage. Some medical information suggests that selenium may help prevent certain cancers, but better studies are needed.
There have also been mixed results regarding selenium's impact on cardiovascular disease.

 
Selenium seems to stimulate antibodies after you receive a vaccination. It also may help protect the body from the poisonous effects of heavy metals and other harmful substances.
Selenium may boost fertility, especially among men. The mineral has been shown to improve the production of sperm and sperm movement.

Food Sources

Plant foods, such as vegetables, are the most common dietary sources of selenium. How much selenium is the vegetables you eat depends on how much of the mineral was in the soil where the plants grew.
Fish, shellfish, red meat, grains, eggs, chicken, liver, and garlic are all good sources of selenium. Meats produced from animals that ate grains or plants found in selenium-rich soil have higher levels of selenium.

 Brewer's yeast, wheat germ, and enriched breads are also good sources of selenium.

Recommendations

Selenium is often available in multivitamin and mineral supplements.
The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for selenium:
Infants

• 0 - 6 months: 15 micrograms per day (mcg/day)
• 7 - 12 months: 20 mcg/day

Children

• 1 - 3 years: 20 mcg/day
• 4 - 8 years: 30 mcg/day
• 9 - 13 years: 40 mcg/day

Adolescents and Adults

• Males age 14 and older: 55 mcg/day
• Females age 14 and older: 55 mcg/day

The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.
Specific recommendations depend on age, gender, and other factors (such as pregnancy). Women who are pregnant or producing breast milk (lactating) need higher amounts. Ask your health care provider which amount is best for you.

Side Effects

Selenium deficiency is rare in people in the United States. However, selenium deficiency may occur when a person is fed through a vein (IV line) for long periods of time.
Keshan disease is caused by a deficiency of selenium. This leads to an abnormality of the heart muscle. Keshan disease caused many childhood deaths in China until the link to selenium was discovered and selenium supplements were provided.


Two other diseases have been linked to selenium deficiency:

• Kashin-Beck disease, which results in joint and bone disease
• Myxedematous endemic cretinism, which results in mental retardation

Severe gastrointestinal disorders may also affect the body's ability to absorb selenium.
Too much selenium in the blood can cause a condition called selenosis. Selenosis can cause loss of hair, nail problems, nausea, irritability, fatigue, and mild nerve damage. However, selenium toxicity is rare in the United States.

References

Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes: Vitamin C, Vitamin E, Selenium, and Carotenoids. National Academy Press, Washington, DC, 2000.
Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.
Hamrick I, Counts SH. Vitamin and mineral supplements. Wellness and Prevention. December 2008:35(4);729-747.

Selenium - antioxidant 

  Selenium is an antioxidant which seems to inhibit cell proliferation. The recommended daily allowance (RDA) of selenium is 70 ug (micrograms) for men, 55 ug for women.

Copper in diet

Definition

Copper is an essential trace mineral present in all body tissues.

Overview & Functions

Copper, along with iron, helps in the formation of red blood cells. It also helps in keeping the blood vessels, nerves, immune system, and bones healthy.

Food Sources

Oysters and other shellfish, whole grains, beans, nuts, potatoes, and organ meats (kidneys, liver) are good sources of copper. Dark leafy greens, dried fruits such as prunes, cocoa, black pepper, and yeast are also sources of copper in the diet.

Recommendations

The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for copper:
Infants

• 0 - 6 months: 200 micrograms per day (mcg/day)
• 7 - 12 months: 220 mcg/day

Children

• 1 - 3 years: 340 mcg/day
• 4 - 8 years: 440 mcg/day
• 9 - 13 years: 700 mcg/day

Adolescents and Adults

• Males and females age 14 – 18 years: 890 mcg/day
• Males and females age 19 and older: 900 mcg/day

The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.
Specific recommendations depend on age, gender, and other factors (such as pregnancy). Women who are pregnant or producing breast milk (lactating) need higher amounts. Ask your health care provider which amount is best for you.

Side Effects

Normally people have enough copper in the foods they eat. Menkes disease (kinky hair syndrome) is a very rare disorder of copper metabolism that is present before birth. It occurs in male infants.
Lack of copper may lead to anemia and osteoporosis.
In large amounts, copper is poisonous. A rare inherited disorder, Wilson's disease, causes deposits of copper in the liver, brain, and other organs. The increased copper in these tissues leads to hepatitis, kidney problems, brain disorders, and other problems.

References

Trumbo P, Yates AA, Schlicker S, Poos M. Food and Nutrition Board, Institute of Medicine, The National Academies. Dietary reference intakes: vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. J Am Diet Assoc. 2001 Mar;101(3):294-301.

Vitamin B12

Definition

Vitamin B12 is a water-soluble vitamin. Water-soluble vitamins dissolve in water. After the body uses these vitamins, leftover amounts leave the body through the urine.
Typically, water-soluble vitamins can not be stored by the body. Vitamin B12 is special, because the body can store it for years in the liver.

Overview & Functions

Vitamin B12, like the other B vitamins, is important for metabolism. It helps in the formation of red blood cells and in the maintenance of the central nervous system

.

Food Sources

Vitamin B12 is found in eggs, meat, poultry, shellfish, milk, and milk products.

Recommendations

The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for vitamin B 12:
Infants

• 0 - 6 months: 0.4 micrograms per day (mcg/day)
• 7 - 12 months: 0.5 mcg/day

Children

• 1 - 3 years: 0.9 mcg/day
• 4 - 8 years: 1.2 mcg/day
• 9 - 13 years: 1.8 mcg/day

Adolescents and Adults

• Males and females age 14 and older: 2.4 mcg/day

Specific recommendations depend on age, gender, and other factors (such as pregnancy). Women who are pregnant or producing breast milk (lactating) need higher amounts. Ask your health care provider which amount is best for you.
The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.

Side Effects

Vitamin B12 deficiencies occur when the body is unable to properly use the vitamin. Pernicious anemia can make the body unable to absorb vitamin B12 from the intestinal tract.
Because vitamin B12 comes primarily from animal products, people who follow a strict vegetarian or vegan diet and do not consume eggs or dairy products may require vitamin B12 supplements. (Non-animal sources of vitamin B12 exist but are highly variable in their B12 content. They are considered unreliable sources of the vitamin.)


Those who had surgery on specific parts of the small intestine or stomach are also prone to a deficiency if they do not take B12 supplements.
Low levels of B12 can cause anemia, numbness or tingling in the arms and legs, weakness, and loss of balance.

References

Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.
Hamrick I, Counts SH. Vitamin and mineral supplements. Wellness and Prevention. December 2008:35(4);729-747.
Mason JB. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 237.

Vitamin B12 benefits 

Vitamin B12 is important for metabolism. Metabolism within the body includes the processes of energy generation and use; including nutrition, digestion, absorption, elimination, respiration, circulation, and temperature regulation.

Vitamin B12 source 

The human body stores several years' worth of vitamin B12, so nutritional deficiency of this vitamin is extremely rare. Although, people who follow a strict vegetarian diet and do not consume eggs or dairy products may require vitamin B12 supplements.
 

 

 

Vitamin D

Definition

Vitamin D is a fat-soluble vitamin that helps the body absorb calcium. Fat-soluble vitamins are stored in the body's fatty tissue.

Overview & Functions

In addition to helping the body absorb calcium, vitamin D also helps the body keep the right amount of calcium and phosphorus in the blood.

Food Sources

Vitamin D is found in the following foods:

• Dairy products
  • Cheese
  • Butter
  • Cream
  • Fortified milk (all milk in the U.S. is fortified with vitamin D)
• Fish
• Oysters
• Fortified cereals
• Margarine

Recommendations

Vitamin D is also known as the "sunshine vitamin" because the body manufactures the vitamin after being exposed to sunshine. Ten to 15 minutes of sunshine 3 times weekly is enough to produce the body's requirement of vitamin D. However, many people living in sunny climates still do not make enough vitamin D and need more from their diet or supplementation.


The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for vitamin D as cholecalciferol. (One microgram of cholecalciferol is the same as 40 IU of vitamin D.)
Infants

• 0 - 6 months: 5 micrograms per day (mcg/day)
• 7 - 12 months: 5 mcg/day

Children

• 1 - 13 years: 5 mcg/day

Adolescents and Adults

• Males and Females age 14 to 50: 5 mcg/day
• Males and Females age 51 to 70: 10 mcg/day
• Males and Females age over 70: 15 mcg/day

Specific recommendations for each vitamin depend on age, gender, and other factors (such as pregnancy). In general, those over age 50 need higher amounts of vitamin D than younger persons. Ask your health care provider which amount is best for you.

Side Effects

Vitamin D deficiency can lead to osteoporosis in adults or rickets in children.
Too much vitamin D can make the intestines absorb too much calcium. This may cause high levels of calcium in the blood. High blood calcium can lead to calcium deposits in soft tissues such as the heart and lungs. This can reduce their ability to function.

 Kidney stones, vomiting, and muscle weakness may also occur if you have too much vitamin D.

References

Hamrick I, Counts SH. Vitamin and mineral supplements. Wellness and Prevention. December 2008:35(4);729-747.
Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.
Mason JB. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 237.

Vitamin D benefit 

  Vitamin D promotes retention and absorption of calcium and phosphorus, primarily in the bones. Too much vitamin D may have the opposite effect of taking calcium from the bones and depositing it in the heart or lungs, reducing their function

Vitamin D deficit 

  Because vitamin D is essential for the body's utilization of calcium, a deficiency may result in severe loss of calcium and consequently a softening and weakening of bones.