Nutrition

The Food Guide Pyramid

The US department of agriculture has devised a powerful and meaningful icon called the food guide pyramid. The pyramid is a graphical depiction of the types of food that one should eat sparingly and in abundance. The food guide pyramid is often shown on cereal boxes, advertisements and other places that provide nutrition related information to the public. The USDA Food guide pyramid contains the following groups of food.

Breads, Cereal, Rice, Pasta Group (6 to 11 servings)

This group consists of the carbohydrate heavy foods and is placed at the bottom of the pyramid indicating that they should be eaten more often and should form an important part of the daily diet. The rationale behind eating more carbohydrates is also that they provide energy and reduce the intake of fat. It is recommended that a person should have 6-11 servings from this group.

Vegetables (3-5 servings) and Fruit (2-4 servings)

There is no doubt that fruit and vegetables are good for the body. They provide the body with essential vitamins and nutrients and ward off diseases and ailments. A person should have 3-5 servings of vegetables and 2-4 servings of fruit a day.

Meat, Poultry, Fish, Dry Beans, Eggs and Nuts Group (2-3 servings)

This group provides the body with proteins. Proteins build the tissues and the muscles. A person should eat 2-3 servings from this group a day.

Milk, Yogurt and Cheese Group (2-3 servings)

This group provides proteins and calcium that makes the bones strong and prevents health problems related to the degeneration of bone mass. A person should eat 2-3 servings from this group a day.

Fats, Oils and Sweets (to be eaten sparingly)

This group should be eaten sparingly. Fat leads to heart disease and obesity. Too much sugar also leads to obesity, which can later create health problems.

The food guide pyramid provides an excellent way to ensure that the body’s nutritional requirements are fulfilled. By following the guidance, an individual will receive all the daily requirements in terms of energy, proteins, vitamins and other essential nutrients while, at the same time, avoiding foods that the consumption of which can lead to health problems.

  • Vegetables: One cup of raw vegetables, or 1/2 cup of cooked vegetables, or 3/4 cup of vegetable juice
  • Fruits: One medium sized fruit (apple or orange), 1/2 cup of canned or chopped fruit, or 3/4 cup of fruit juice
  • Breads and cereals: One slice of bread; 1 ounce or 2/3 cup of ready-to-eat cereal; 1/2 cup of cooked rice, pasta, or cereal; 1/2 cup of cooked dry beans, lentils, or dried peas
  • Dairy: One cup of skimmed or low fat milk
  • Fat

    Fat is one of the three nutrients (along with proteins and carbohydrates) that supply calories to the body. It provides nine calories per gram, more than twice the number provided by carbohydrates or proteins. It is essential for the proper functioning of the body. Fats provide the “essential” fatty acids, which are not made by the body and must be obtained from food. The Linoleic acid is the most important essential fatty acid, especially for the growth and development of infants. Fatty acids provide the raw materials that help in the control of blood pressure, blood clotting, inflammation, and other body functions. 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 in the absorption, and transport through the bloodstream of the fat-soluble vitamins A, D, E, and K.

    Saturated Fats

    Saturated fats tend to be solid at room temperature. They are the biggest dietary cause of high LDL (“bad cholesterol”) levels. When looking at a food label, pay very close attention to the % of saturated fats and avoid or limit any foods that are high in (contain over 20% of) saturated fats. 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 such as coconut, palm, and palm kernel oils. (Note: Most other vegetable oils contain unsaturated fat and are healthy.) 

    Unsaturated Fats

    Unsaturated fats tend to be liquid at room temperature. These fats 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. Unsaturated fats are of two types: mono-unsaturated and polyunsaturated. Most (but not all) liquid vegetable oils are unsaturated. (The exceptions include coconut, palm, and palm kernel oils.)  

  • Mono-unsaturated fats help lower blood cholesterol if used in place of saturated fats. However, mono-unsaturated fats have a lot of calories. So you still need to limit their consumption. Examples include olive and canola oils.
  • Polyunsaturated fats also help lower blood cholesterol if used in place of saturated fats. However, polyunsaturated fats also have a lot of calories. So you still need to limit their consumption. Examples include safflower, sunflower, corn, and soybean oils.
  • Trans-Fatty Acids

    These fats form when vegetable oil hardens (is hydrogenated). They can raise LDL levels. They can also lower HDL (“good cholesterol”) levels. Trans-fatty acids are found in fried foods, baked commercial goods (donuts, cookies, crackers etc), processed foods, and margarines. 

    Hydrogenation

    The term hydrogenated refers to the hardening of oils when they mix with oxygen. Hard butter and margarine are examples of such foods. 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.) The terms “hydrogenated” and “saturated” are related; an oil becomes saturated when hydrogen is added to it (i.e. when it becomes hydrogenated).

    Eating too much saturated fat is one of the major risk factors responsible 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 responsible for heart disease and some types of cancer). A large intake of polyunsaturated fat may increase the risk of 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. Choose lean, protein-rich foods soya, fish, skinless chicken, very lean meat, and fat free or 1% dairy products. Eat foods that are naturally low in fat — whole grains, fruit, and vegetables. Get plenty of soluble fiber with oats, bran, dry peas, beans, cereal, and rice. Limit your consumption of fried foods, processed foods, and commercially prepared baked goods (donuts, cookies, crackers).

    Carbohydrates

    Carbohydrates are sometimes referred to as starches, simple sugars and sugars. They constitute one of the main dietary components. This category of foods includes sugars, starches, and fiber. The primary function of carbohydrates is to provide energy for the body, especially the brain and the nervous system. Your liver breaks down carbohydrates into glucose (blood sugar), which is used as a source of energy by the body. Carbohydrates are classified as simple or complex. The classification depends on the chemical structure of the particular food source and reflects how quickly the sugar contained in it is digested and absorbed. 

    There are three basic types of carbohydrates – simple, complex and very complex. Out of these, the last two types are essential components of a healthy diet.

  • Simple carbohydrates (also called sugars): Simple carbohydrates can be found in white sugar, preservatives, candies, coke, cake, juice concentrates, honey and glucose syrup. They are made up of single or double molecules and are quickly absorbed into the blood stream.
  • Complex carbohydrates: Foods that are high in complex carbohydrates include whole grain bread, pasta, rice, beans, vegetables and potatoes. They are made up of complex molecules and the body requires time to digest them, which means that we feel full for a longer period after eating them.
  • Very complex carbohydrates (also known as fiber): These carbohydrates add bulk to our food, which helps in digestion. They are found in whole meal bread and phsylum husk. Fibers help to ease the flow of food through the intestines, reduce the risk of diabetes and lower cholesterol. Thirty o thirty five grams of fiber a day is the ideal amount, which is very beneficial for the body. Very complex carbohydrates have an extremely complex molecular structure.
  • Carbohydrates taken in excess can cause an increase in the total caloric intake and thus lead to obesity. On the other hand, deficiency of carbohydrates can lead to a lack of calories (malnutrition). Low consumption of carbohydrates can also stand in the way of making up the calories lost through work or exercise. For most people, 40% to 60% of the total calories required should come from carbohydrates, preferably from complex carbohydrates (starches) and naturally occurring sugars that can be found in fruit. Complex carbohydrates provide calories, vitamins, minerals, and fiber to the body. Foods that are high in processed, refined simple sugars provide calories, but they have few nutritional benefits. It is wise to limit the consumption of such sugars.

    To increase the intake of complex carbohydrates and healthy nutrients

  • Eat more fruit and vegetables.
  • Eat more whole grains, rice, breads, and cereals.
  • Eat more legumes (beans, lentils, and dried peas).
  • Proteins

    Proteins are complex organic compounds. The basic structure of proteins is a chain of amino acids. They are the main component of muscles, organs, and glands. Every living cell and all body fluids, except bile and urine, contain proteins. The cells of the muscles, tendons, and ligaments are maintained with their help. Children and adolescents require proteins for growth and development. Proteins are categorised as essential and nonessential proteins or amino acids. The human body requires approximately twenty amino acids for the synthesis of its proteins. Out of these, the body can make only thirteen. These thirteen are known as nonessential amino acids because the body can make them and does not need to get them from the diet. There are nine essential amino acids that are obtained only from food and not made in the body. If the protein in a food supplies enough of the essential amino acids, it is called a complete protein. If it does not supply all the essential amino acids, it is called an incomplete protein. 

    All meat and other animal products are sources of complete proteins. These include beef, lamb, pork, poultry, fish, shellfish, eggs, milk, and milk products. The protein content in foods such as grains, fruits, and vegetables is incomplete protein as it lacks one or the other of the essential amino acids. Plant proteins can be combined to include all of the essential amino acids and form a complete protein. Examples of combinations which form complete plant protein sources are rice and beans, milk and wheat cereal, and corn and beans. 

    A diet high in meat can lead to high cholesterol or other diseases such as gout. Another potential problem is that a high-protein diet may put too much strain on the kidneys. Extra waste matter, which is the end product of protein metabolism, is excreted through the urine. A nutritionally balanced diet provides adequate proteins to the body. Vegetarians are able to get enough proteins if they eat the proper combinations of plant foods. The amount of recommended daily protein intake depends upon age, medical conditions, and the type of diet one is following. Two to three servings of protein-rich food will meet the daily needs of most adults. Meats are an ideal source of proteins. Fresh meats are far better to eat than processed meats, which contain up to 30% more fat and preservatives.