Basic Knowledge on Nutrition

DEFINITION OF HEALTH

According to WHO “Health is a state of complete physical, mental, social well being and not merely the absence of disease or infirmity.”

To maintain good health, ingesting a diet containing essential nutrients in correct amounts is very important.

CHECKING OUT CALORIES

Everyday we have been hearing so much about calories as in low–calorie foods or low-calorie dinners on menus, diet foods, drinks with just one calorie, calorie free sweetner etc. So what is a calorie?

A calorie is a measure of how much energy the nutrients protein, carbohydrate, and fat can supply your body. Some types of nutrients have more calories than others.

Fat:	1 gram gives 9 calories
Protein:	1 gram gives 4 calories
Carbohydrates:	1 gram gives 4 calories
Alcohol:	1 gram gives 7 calories

IDEAL WEIGHT VS HEALTHY WEIGHT

Do you dream of an “ideal “weight – a number on a chart, a figure in your head? In reality, no specific ideal weight can be assigned to any one individual. What you should weigh depends on many factors. So rather than over reaching an ideal weight its better to shoot for a healthy body weight and a healthy body composition.
There are different ways in which ideal weight is calculated.

DESIRABLE WEIGHTS FOR ADULT MEN (in Pounds, 1 kg = 2.2 lb)
Height		Small Frame	Medium Frame	Large Frame
Feet	Inches
5	4	118-126	124-136	132-148
5	5	121-129	127-139	135-148
5	6	124-133	130-143	138-156
5	7	128-137	134-147	142-161
5	8	132-141	138-152	147-166
5	9	136-145	142-156	151-170
5	10	140-150	146-160	155-174
5	11	144-154	150-165	159-179
6	0	148-158	154-170	164-184
6	1	152-162	158-175	168-189
6	2	156-167	162-180	173-194
6	3	160-171	167-185	178-199
6	4	164-175	172-190	182-204

DESIRABLE WEIGHTS FOR ADULT WOMEN(in Pounds, 1 kg = 2.2 lb)
Height		Small Frame	Medium Frame	Large Frame
Feet	Inches
4	10	92-98	96-107	104-119
4	11	94-101	98-110	106-122
5	0	96-104	101-113	109-125
5	1	99-107	104-116	112-128
5	2	102-110	107-119	115-131
5	3	105-113	110-122	118-134
5	4	108-116	113-126	121-138
5	5	111-119	116-130	125-142
6	6	114-123	120-135	129-146
6	7	118-127	124-139	133-150
6	8	122-131	128-143	137-154
6	9	126-135	132-147	141-158
6	10	130-140	136-151	145-163

Another method is calculating the Body Mass Index (BMI).

BMI = Weight in kg. / (Height in meter) 2

• BMI of 19 – 24.9 is normal
• BMI of 25 – 30 is considered overweight
• BMI of 30 indicates obesity

Measuring Waist to Hip ratio is also an indicator of obesity. A ratio of over 0.8 for women and 1.0 for men is considered to be obese. A higher waist to hip ratio is correlated to heart disease.

MACRONUTRIENTS

CARBOHYDRATES

Carbohydrates can be classified in three categories: simple carbohydrates, complex carbohydrates, and fiber. All three consist of combinations of sugars (glucose, galactose, or fructose) bound together.

Both simple and complex carbohydrates are easily digested and absorbed by the body for use as a source of energy. While proteins and fats can be broken down and converted into energy, it is generally far more efficient for the body to use carbohydrates for this function.

Examples of Simple and Complex Carbohydrates and Common Food Sources:
Simple Carbohydrates and Food Sources
Glucose: The single-unit carbohydrate that all other carbohydrates are broken down into for use by the body Sucrose: Beet and cane sugar, brown sugar, maple syrup, honey Fructose: Fruits, some vegetables, sweeteners such as high-fructose corn syrup, honey Lactose: Milk and dairy products Sucrose: Sugar, beets, fruit
Complex Carbohydrates and Food Sources
Fibers and starches: Grains such as bread, pasta, beans, potatoes, corn and other vegetables, legumes, wheat

ROLE OF CARBOHYDRATE IN THE BODY

Carbohydrates have an important job: giving all the cells in your body the energy they need! Carbohydrates are the only source of energy that the brain and central nervous system can use. Muscles also need a steady supply of carbohydrates, in basic form of glucose, to contract. The minimum amount of carbohydrates needed daily to prevent a deficiency is the Recommended Dietary Allowance of 130 grams of carbohydrates daily with an intake of 40 gm of fiber per day. Although no RDA exists for carbohydrates, nutritionists generally recommend that at least 60-65% percent of calories come from carbohydrates, with an emphasis on complex carbohydrates (only about 10 percent of calories should come from simple carbohydrates).

FIBER: A SPECIAL CARBOHYDRATE

Unlike other carbohydrates, dietary fiber is unavailable as an energy source. This nutrient cannot be broken down by digestive enzymes and consequently passes through the intestine without being absorbed

They are classified into two general categories: soluble and insoluble. Soluble fibers dissolve in water and include pectin, guar, carrageen an, gums, mucilage, and oat bran. Soluble fibers help to lower the blood cholesterol levels. Insoluble fibers do not seem to affect serum cholesterol levels, but they do help prevent constipation. Insoluble fibers include cellulose, hemi cellulose, and lignin.

CARBOHYDRATE MYTHS

• Carbohydrates are fattening and will make you gain weight. In fact, since starchy foods like bread, pasta, legumes, and vegetables do not generally contain much fat (unless added in the form of butter, cooking oils, or rich sauces), these foods tend to be quite low in calories by weight (carbohydrates contain only 4 calories per gram). Also, research shows that the body less easily turns carbohydrates into body fat than it does oil and other fats.
• Eating too much sugar causes diabetes. Diabetes is not caused by sugar consumption, but people with diabetes may be unable to eat much sugar because either their bodies are incapable of producing adequate amounts of insulin or their bodies are insensitive to the insulin that they do produce. Many people, especially children, who develop diabetes, have a history of the disease in their family. In addition, being overweight can greatly increase the likelihood of developing diabetes as an adult.

PROTEINS

Proteins are composed of compounds called amino acids linked end to end. The number and sequence of different amino acids are what gives each protein its unique characteristics. Of the 20 different amino acids, the body can manufacture all but 9; the 9 the body is unable to synthesize on its own are called "essential" amino acids. The term ‘essential’ refers not to the relative importance of these 9 amino acids (all amino acids are necessary for optimal health) but denotes the body's dependency on the diet as a source of these substances. The remaining amino acids that the body is able to synthesize are known as "nonessential" amino acids.

ROLE OF PROTEIN IN THE BODY

Everyone knows that protein is important for building muscle and repairing muscle fibers after exercise, but proteins in the body have thousands of other essential roles, including:

• Producing antibodies for the immune system.
• Manufacturing hormones and enzymes that are involved in most reactions in your body.
• Aiding in the digestion and absorption of food.
• Being a source of fuel when muscle glycogen levels are low.
• Maximizing the transport of oxygen to tissues.
• Providing structure for muscles, tendons, ligaments, organs, bones, hair, skin and all other tissues.

SOURCES

Protein is classified as complete or incomplete, depending upon its amino acid profile. If the protein contains all the amino acids needed to construct new proteins, it’s considered a complete protein. Animal sources of protein such as meat, poultry, fish and dairy products are complete proteins. Other protein sources may lack one or more of the essential amino acids and are therefore called incomplete proteins. Incomplete proteins come from plant-based foods such as fruits, vegetables, grains and nuts. Soy protein is considered a complete protein because it contains all the essential amino acids.

Two or more incomplete, vegetable-based proteins can be eaten so that the body has all of the essential amino acids and form a complete protein. Examples of combined, complete plant proteins are rice and beans, milk and wheat cereal, and corn and beans. There is no need to combine specific foods at meals to create complete proteins, as once thought. If you eat adequate calories and a variety of plant-based foods, your body will create enough complete proteins out of the amino acid pool.

Eat More	Eat Less
Dals & Beans	Red meats
Egg whites	Egg yolks
Low fat/Skim milk and milk products	Full-fat milk & milk products
Chicken & Fish	Shellfish & Organ meat
Wholegrain cereals
1 gm of protein gives 4 calories

RDA

Many people believe large amounts of protein are required to fulfill all the body's functions. In reality quite modest amounts satisfy our physiological needs. No specific level of intake, or RDA (Recommended Dietary Allowance), has been established for protein, in part, because individual requirements vary dramatically according to age (babies and growing children need more than adults) and a variety of special circumstances. For example, pregnancy and breast-feeding both increase protein requirements, as does illness or other types of stress. While current dietary recommendations suggest that 12 to 15 percent of total daily calories should come from protein.

PROTEIN MYTHS

Because protein has a traditionally healthy image, false myths about this nutrient are widespread.

• Eating additional protein will enhance muscle development, increase strength, and improve athletic performance. Although amino acid supplements are widely promoted, particularly for use among athletes and bodybuilders, they have no proven benefit. In fact, supplements can lead to nutritional imbalances by providing too much of some amino acids and little or none of others.
• Protein is denser in calories than carbohydrates. Protein and carbohydrates have the same caloric density 4 calories per gram but foods high in protein, such as meats, whole milk, and cheese, may be more fattening than foods rich in carbohydrates because they often contain large amounts of fat. Because of this association with fat, protein rich foods need to be selected carefully, with an eye toward consuming low fat alternatives (e. g., lean cuts of meat, low fat or nonfat milk, and cheeses made with part skim milk).
• High proteins diets help reduce weight. High protein diets used to be extremely popular for quick weight loss. However, much of this weight is water. (More water is required in the metabolism of carbohydrate than in the metabolism of protein, and a low carbohydrate diet causes water loss.) High protein diets can be dangerous. Never attempt this sort of diet without a doctor's supervision.

FAT

Fat sometimes sounds like it's always a bad thing that people should not eat, but actually our bodies need some fat to work correctly. There are “good” and “bad” fats that either help protect you from diseases or increases your risk for chronic conditions. The so-called healthy fats are monounsaturated or polyunsaturated fats and the bad fats are saturated fats or trans fats. When monos or polys are substituted for saturated fat or trans fats in the diet, they lower total blood cholesterol and triglycerides and raise healthy, HDL-cholesterol levels in the blood. They also improve insulin sensitivity and blood pressure. Saturated fat and trans fats may promote heart disease, diabetes, certain cancers and obesity because they raise LDL cholesterol levels, aggravate inflammation in the arteries, elevate triglycerides and trans fats lower healthy HDL cholesterol levels.

ROLE OF FAT AND SOURCES

• Fat insulates our bodies from the cold and provides some cushioning for our organs.
• Fat gives our bodies energy.
• Some fats help to make up important hormones that we need to keep our bodies at the right temperature or keep our blood pressure at the right level.
• Fat helps you have healthy skin and hair.
• Fat is like your body's very own storage and moving service: it helps vitamins A, D, E, and K hang out and get transported through your bloodstream when your body needs them!

Saturated Fat:	• Tends to increase blood cholesterol levels. Most saturated fats tend to be solid at room temperature, with the exception of tropical oils. • Found mostly in meat and dairy products, as well as some vegetable oils, such as coconut and palm oils (tropical oils). Butter is high in saturated fat, while margarine tends to have more unsaturated fat.
Polyunsaturated Fat:	• Tends to lower blood cholesterol levels • found mostly in plant sources. (safflower, sunflower, soybean, corn, cottonseed)
Monounsaturated Fat:	• Tends to lower LDL cholesterol (the "bad" cholesterol) • found in both plant and animal products, such as olive oil, canola oil, peanut oil, and in some plant foods such as avocado

Fat should account for 20% or less of the calories consumed daily, with saturated fats accounting for no more than 7% of the total fat intake.

Excess calories from protein and carbohydrates are converted to and stored as fat. Even if you are eating mostly "fat free" foods, excess consumption will result in additional body fat. Fat calories in food are readily stored, while it takes energy to transform protein and carbohydrates to body fat. The only proven way to reduce body fat is to burn more calories than one consumes

The body manufactures most of the fatty acids it needs from other nutrients, but is unable to make its own linoleic and linolenic acid. Known as "essential" fatty acids, linoleic and linolenic acid should both be consumed daily in small amounts (for instance, 1 teaspoon per day of polyunsaturated fats like corn or safflower oil are sufficient to fulfill the body's requirements)

Eat in moderation (Unsaturated fats)	Eat Less / Avoid (Saturated fats)
Oils high in poly-unsaturated fatty acids like sunflower, safflower, corn & soya Oils high in mono-unsaturated fatty acids like groundnut, olive * mustard Nuts Seeds	Butter & Ghee * Lard * Vanaspati Cheese * Coconut & Palm oils Egg yolks * Red meat * Shellfish * Coconut Cream *
1 gm of fat gives 9 calories *contain cholesterol

CHOLESTEROL

Cholesterol is a form of lipid called a sterol (technically, cholesterol is not a fat). While some cholesterol is consumed in the diet but is present only in foods from animals such as meat, butter, and eggs the body from fatty acid precursors manufactures most of the cholesterol in our bodies.

Dietary cholesterol is only found in foods from animal sources, including meat, fish, milk, eggs, cheese, and butter, HDL and LDL are lipoproteins, substances found in the bloodstream, which transports cholesterol and triglycerides in the body.

Cholesterol intake should not exceed 300 milligrams a day. Individuals differ on their absorption of dietary cholesterol, what is important is one’s level of blood cholesterol. High blood cholesterol has been linked to the occurrence of arteriosclerosis. Arteriosclerosis is a buildup of fatty deposits in the coronary arteries and other blood vessels, and is a leading cause of heart attacks.

• HDLs help remove cholesterol from the blood, protecting you from heart disease (atherosclerosis).
• LDLs are thought to deposit cholesterol in artery walls, increasing your risk of heart disease (atherosclerosis). Most abundant type, LDL carries approximately 65% of the total circulating cholesterol. High levels of LDL are associated with arteriosclerosis.

FAT BUSTING TIPS

• Use a non-stick pan for cooking.
• Grill or bake food instead of frying.
• Have low fat/skim dairy products.
• Remove fat from meat & skin from chicken.
• Defat soups, stocks and gravies by refrigerating them for a few hours before use.
• Cook vegetables without fat by streaming and boiling.
• Use low fat spreads and chutney on bread instead of butter and cheese.
• Serve dressings and rich sauces separately so that you can minimize their intake.
• Have plain bread and chapattis instead of rolls, puris and parathas.
• Replace high-fat ingredients in your favorite recipes with healthier substitutes e.g. use yogurt instead of cream.

VITAMINS AND MINERALS

Vitamins and minerals are required for the regulation of the body's metabolic functions, and are found naturally in the foods we eat. Many foods are fortified in order to provide additional nutrients, or to replace nutrients that may have been lost during the processing of the food. Most people are able to obtain satisfactory nutrition from the wide selection of foods.

If a person is not able to eat a variety of foods from the basic food groups, then a vitamin and mineral supplement may be necessary. Large doses of vitamin and mineral supplements can be harmful.

Vitamins come in two varieties: fat soluble and water-soluble. Fat-soluble vitamins can be stored in the body for long periods of time, while excess amounts of water-soluble vitamins are excreted in the urine.

FAT SOLUBLE VITAMINS

Vitamin A	• Needed for new cell growth, healthy skin, hair, and tissues, and vision. • Sources: dark green and yellow vegetables and yellow fruits, such as broccoli spinach, turnip greens, carrots, sweet potatoes, pumpkin and apricots, and in animal sources such as liver, milk, butter, cheese, and whole eggs.
Vitamin D	• Promotes absorption and use of calcium and phosphate for healthy bones and teeth • sources: milk (fortified), cheese, and whole eggs, liver, salmon. The skin can synthesize vitamin D if exposed to enough sunlight on a regular basis.
Vitamin E	• Protects red blood cells and helps prevent destruction of vitamin A and C • sources: margarine and vegetable oil (soybean, corn, safflower, and cottonseed), wheat germ, green leafy vegetables.
Vitamin K	• Necessary for normal blood clotting and synthesis of proteins found in plasma, bone, and kidneys. • Sources: spinach, lettuce, cabbage, cauliflower, wheat bran, organ meats, cereals, meats, dairy products, and eggs.

WATER SOLUBLE VITAMINS

Vitamin C (Ascorbic acid)	• An antioxidant vitamin needed for the formation of collagen to hold the cells together and for healthy teeth, gums and blood vessels; improves iron absorption and resistance to infection. • Sources: many fresh vegetables and fruits, such as broccoli, green and red peppers, guava, amla, cauliflower, lemon, cabbage, pineapples, strawberries, citrus fruits
Thiamin (B1)	• Needed for energy metabolism and the proper function of the nervous system • sources: whole grains, soybeans, peas, liver, kidney, and lean cuts of pork, legumes, seeds, and nuts.
Riboflavin (B2)	• Needed for energy metabolism, building tissue, and helps maintain good vision. • Sources: dairy products lean meats, poultry, fish, grains, broccoli, turnip greens, and spinach.
Niacin (B3)	• Needed for energy metabolism, proper digestion, and healthy nervous system • sources: lean meats, liver, poultry, milk, canned salmon, leafy green vegetables
Vitamin B6 (Pyridoxine)	• Needed for cell growth • sources: chicken, fish, pork, liver, kidney, whole grains, nuts, and legumes
Folate (Folic Acid)	• Promotes normal digestion; essential for development of red blood cells • sources: liver, yeast, dark green leafy vegetables, legumes, and some fruits
Vitamin B12	• Needed for building proteins in the body, red blood cells, and normal function of nervous tissue • sources: liver, kidney, yogurt, dairy products, fish, clams, oysters, nonfat dry milk, salmon, sardines

MINERALS

Calcium	• Needed for healthy bones and teeth, normal blood clotting, and nervous system functioning • sources: dairy products, broccoli, cabbage, tofu, sardines and salmon
Iron	• Needed for the formation of hemoglobin, which carries oxygen from the lungs to the body cells • sources: meats, eggs, dark green leafy vegetables, legumes, whole grains.
Phosphorus	• Needed for healthy bones and teeth, energy metabolism, and acid base balance in the body • sources: milk, grains, lean meats, food additives
Magnesium	• Needed for healthy bones and teeth, proper nervous system functioning, and energy metabolism • sources: dairy products, meat, fish, poultry, green vegetables, legumes
Zinc	• Needed for cell reproduction, tissue growth and repair • sources: meat, seafood, and liver, eggs, milk, whole-grain products
Pantothenic Acid	• Needed for energy metabolism • sources: egg yolk, liver, kidney, yeast, broccoli, lean beef, skim milk, sweet potatoes.
Copper	• Needed for synthesis of hemoglobin, proper iron metabolism, and maintenance of blood vessels • sources: seafood, nuts, legumes, green leafy vegetables
Manganese	• Needed for enzyme structure • sources: whole grain products, fruits and vegetables, tea

WATER

We don't often think of water as a nutrient, but it is as important to our health as any of the nutrients. This may seem obvious, as we know life cannot be sustained without water. The human body is made up of 60 - 75% water and every cell of the body uses water. All the many biochemical reactions and metabolic processes that take place in the body depend on water. The body cannot function optimally or efficiently when it is not well hydrated with fluids. Water is the primary component of our body fluids; it aids in digestion, provides the vehicle for circulating nutrients and oxygen through the body, as well as for the elimination of waste. It helps lubricate joints, protect organs, and maintain normal body temperature. A well-hydrated body is necessary for optimal exercise and athletic performance.

Water Losses

On average, your body losses 8 - 12 glasses of water a day. This is increased by:

• Exercise
• Hot weather
• Low humidity
• Altitude
• High fiber diet
• Consumption of caffeine and alcohol containing beverages

Fluid Replacement

In general men need to replace about 12 glasses of fluid daily and women need to replace 8 -10 cups. Not all of this fluid is generally replaced by drinking water, although water is the major way of meeting your fluid needs. Fluid can be replaced by:

• Water
• Non-caffeine, non-alcoholic beverages
• Soups
• Water found naturally in foods (vegetables and fruits are high in water)
• Drink at least 8 - 10 glasses of water a day.

Tips for increasing your water consumption:

• At work keep a large water bottle on your desk.
• At home keep a pitcher of water in your refrigerator.
• Carry a water bottle with you when you leave the house.
• Change to decaffeinated coffee, tea and soda, instead of caffeinated beverages.
• For every caffeinated beverage you drink, drink a glass of water.
• Drink a glass of water before meals and snacks.
• Order water at restaurants.
• Add lemon or lime to your water if it allows you enjoy water more.