Although these guidelines are developed by the US Department of Agriculture and the Department of Health and Human Services for healthy Americans, they have received the consensus by most authorities, and can be used by *healthy people throughout the world.
*Healthy refers to people who do not suffer from malnutrition or any other condition that requires a change in dietary guidelines or nutrient allowances.
The 1990 Dietary Guidelines for Americans.
- Eat a variety of foods.
- Maintain healthy weight.
- Choose a diet low in fat, saturated fat, and cholesterol.
- Choose a diet with plenty of vegetables, fruits, and
- Use sugars only in moderation.
- Use salt and sodium only in moderation.
- If you drink alcoholic beverages, do so in moderation.
People should focus on their total diet in a more positive way, especially with respect to fat and cholesterol. Most people following a Western type diet are consuming far too much fat and cholesterol, and not enough carbohydrate and fiber.
The easy way to overcome this problem is to eat moderate amounts of foods from all the different food groups, and avoid dietary extremes that include an excess of fatty foods, cholesterol, or sugars.
Eat a Variety of Foods:
All foods that supply calories and essential nutrients, potentially, can be included in an adequate diet. In some cases, certain groups of people (eg. pregnant women, vegetarians) should eat foods to obtain a greater amount of a particular nutrient (eg. calcium-rich foods, iron-rich foods). But, when choosing a greater variety of foods from the different food groups, choose low-calorie foods, especially for elderly persons and persons who are sedentary or trying to loose weight.
No single food can supply all the nutrients in the amounts you need. To make sure you eat all the nutrients and other substances needed for health, choose the recommended number of servings from each of the food groups displayed in the Food Guide Pyramid.
Maintain Healthy Weight:
A healthy weight is the weight a person should be to live a healthy life, and reduce the chances of conditions that are associated with either obesity or malnutrition caused from hunger and starvation. "Too lean" is a health problem often found in young women, too easily influenced by the peer pressure of modern living. They strive to loose weight even when they are under-weight.
A healthy weight can be calculated by considering body mass index and waist-to-hip ratio. If a person is over-weight, and this is not caused by a weight-related disease, the importance of following one of the many weight reduction strategies and the necessity to exercise and increase the amount of energy expended, is paramount.To maintain weight you must balance the energy in food with the amount of energy your body uses. Physical activity is an important way to use up food energy. To use up dietary energy spend more time being physically active, like walking the dog, and less time being inactive, like watching television.
Ratios of weight to height estimate total body mass rather than fat mass, but they correlate highly with the amount of body fat. [Revicki, D.A. and Israel, R.G. Relationship between body mass indices and measure of body adiposity. American Journal of Public Health 76:992-94, 1986] The most commonly used ratio is known as Quetelet's index, or the BMI, and is usually defined as body weight in kilograms divided by the square of the height in meters (wt/ht2).
Table 2.1 Body Mass Index Used to Define Desirable Weight and Overweight for "Ideal" Reference Populations
Mean | Overweight | Severe Overweight | |||
Men | Women | Men | Women | Men | Women |
22.0 | 21.5 | 26.4 | 25.8 | 30.8 | 30.1 |
A reasonable weight reduction program should have a goal of � to 1 pound per week. Loosing more than 1 pound a week is not recommended, nor should drugs or other extreme means of weight reduction be used (See chapter on Dietary Fads and Frauds).Extreme approaches to weight loss, such as self induced vomiting or the use of laxatives, amphetamines, or diuretics, are not appropriate and can be dangerous to health.
The table that follows lists healthy weight ranges for adults.
Height | Weight (in Pounds) |
4' 10" | 91 - 119 |
The higher values in the weight range apply to people with more muscle and bone. Weights above this range are less healthy for most people.
Choose a Diet Low in Fat, Saturated Fat and Cholesterol:
As already stated, there is a need for people following a Western Diet to reduce the amount of fat, saturated fat and cholesterol that they consume. Only about 25 percent of calories should come from fats, and no more than 10 percent from saturated fats.
Risk for heart disease is increased among people with elevated blood cholesterol levels. It is important to get your blood cholesterol checked regularly. If blood cholesterol is above 5.2 mmol/L, follow the advice of health professionals about diet and if necessary medication.Fat, whether from plant or animal sources, contains more than twice the number of calories as an equal amount of carbohydrate or protein. Each gram of fat contains 9 calories. Some foods and food groups are higher in fat than others. This guideline emphasizes the continued importance of choosing a diet with less total fat, saturated fat, and cholesterol.
Choose a Diet with Plenty of Vegetables, Fruits and Grain Products:
Foods that provide complex carbohydrates, dietary fiber, and other components are linked to good health, mainly by lowering the fat content in the diet. This guideline is consistent with the scientific evidence that supports the health benefits of diets with more complex carbohydrates and a variety of fiber-rich foods.
Most of the calories in your diet should come from grain products, fruits and vegetables.These include bread, cereals, pasta, rice and potatoes. Dry beans are included in the meat group but can also count as servings of vegetables. Plant foods are generally low in fats, depending on how they are prepared and what is added to them.
Fiber is found only in plant foods. Eating a variety of fiber-containing foods is important for proper bowel function and can reduce the risk of chronic constipation, diverticular disease, heart disease and some cancers.
Use Sugars in moderation:
Sugars include all simple carbohydrates, such as sucrose, glucose and lactose, and foods containing them such as candies, honey, and chocolate.
Sugars and foods containing them in large amounts supply energy but are limited in nutrients. Furthermore, sugars and starches, which break down in the mouth, can contribute to tooth decay. The importance of fluoride and dental hygiene in the prevention of tooth decay is also stressed.
Sugar substitutes do not provide significant calories and may be used to reduce calorie intake. However, foods containing sugar substitutes may not always be lower in calories than similar products that do contain sugar. Unless you reduce the total calories you eat, the use of sugar substitutes will not cause you to lose weight.
Use Salt and Sodium in Moderation:
Sodium plays an essential role in regulating fluids and blood pressure. However many studies have shown that a high sodium intake is associated with high blood pressure. Eating foods high in potassium helps to counter the effects of high sodium consumption on blood pressure.
Using less salt and sodium than is normally used will benefit those people whose blood pressure goes up with salt intake. Hereditary factors as well as excessive drinking have also been shown to be related to high blood pressure. Adults are encouraged to get their blood pressure checked and, if it is high, to consult a physician about diet.
It is easy to reduce sodium intake by using less salt in cooking and on the table, but when eating processed foods it is important to look on the label for sodium substances, as these are used excessively in many types of sauces and condiments.
If You Drink Alcoholic Beverages, Do So in Moderation:
Alcohol has no net benefit to health and is not an essential nutrient in any way. If you can not avoid drinking, do so in moderation. One or two drinks per day are not usually associated with health risks.
Inflammation of the pancreas and damage to the heart and brain are some of the complications of drinking. Studies have shown that alcohol is linked to risks of heart attacks, hypertension, haemorrhagic stroke, cirrhosis of the liver, inflammation of the pancreas, violence, suicide, birth defects and overall mortality.
Table 2.2 A comparison of recent government dietary recommendations for some nutrients.
Surgeon General's Report on Nutrition and Health. | National Research Council's Diet and Health. |
Fat and cholesterol | |
Reduce consumption of fat (especially saturated fat) and cholesterol. | Reduce total fat intake to 30% or less. Reduce saturated fatty acid intake to less than 10% of total calories, and intake of cholesterol to less than 300 mg daily. |
Energy and weight control | |
Achieve and maintain a desirable body weight. To do so, choose a diet in which caloric intake is consistent with energy expenditure. | Balance food intake and physical activity to maintain appropriate body weight. |
Complex carbohydrate and fiber | |
Increase consumption of whole grain foods and cereal products, vegetables (including dried beans and peas), and fruits. | Everyday eat five or more servings of a combination of vegetables and fruits, especially green and yellow vegetables and citrus fruits. Increase intake of starches and other complex carbohydrates by eating six or more daily servings of a combination of breads, cereals, and legumes. |
Sodium | |
Reduce intake of sodium by choosing foods low in sodium and limiting the amount of salt added in food preparation and at the table. | Limit total daily intake of salt to 6 gm or less. Limit salt in cooking and avoid adding it to foods at the table. |
Calcium | |
Adolescent girls and adult women should increase consumption of foods high in calcium, including low-fat dairy products. | Maintain adequate calcium intake. |
Calorie Requirements
In addition to requiring a certain amount of nutrients, your body also requires a certain amount of calories daily. Total energy expenditure includes the energy expended in rest, in physical activity, and as a result of thermogenisis. These components, in turn, are affected by several variables, including age, sex, body size and composition, genetic factors, energy intake, physiologic state (eg. growth, pregnancy, lactation), coexisting pathological conditions, and ambient temperature.
- Resting Metabolic Rate represents the minimum energy needs of the body, for day and night with no exercise or exposure to cold.
- Sedentary includes occupations that involve sitting most of the day, such as office work and studying.
- Light includes activities which involve standing most of the day, such as teaching or laboratory work.
- Moderate may include walking, gardening, and housework.
- Active includes dancing, skating, and manual labor such as farm or construction work.
Table 2.3 Daily calorie allowance.
MEN | WOMEN | |
Activity level | Calories required | |
Resting | 12 per lb. body weight | 13 per lb. body weight |
Using the chart you can determine the amount of calories you require daily, depending on your activity level . For example a 130 pound male waiter requires 2730 calories. (Moderate activity level 21 x 130 lb = 2730 Cal.)
The following table indicates the approximate number of calories used by the body during a half-hour of the activity.
Table 2.4 Energy expenditure.
ACTIVITY | ENERGY |
Badminton | 220 |
Metabolism
The person who can eat and eat and never gain a pound probably does not exist, according to a recent US Department of Agriculture study.
The study should help resolve two conflicting schools of thought on whether a person's metabolism automatically gears up to prevent weight gain when eating extra calories day after day. The findings show very little change in metabolism.
For three weeks, seven men consumed 1000 kcal more each day than they would normally eat. All of them gained weight, on average a ¼ lb per day.
After the men stopped overeating, they dropped weight rapidly, even though they were told not to diet. They unconsciously chose fewer calories than they would normally eat, primarily by avoiding high-fat foods.
This supports the hypothesis that successful body weight regulation might be associated with body fat and carbohydrate levels rather than by a single factor such as total energy level. The men had plenty of fat reserves, so they selected less fat.
While it's not uncommon for a persons' caloric intake to vary 1000 kcal from day to day, it's not easy to eat an extra 1000 kcal day after day. The men consumed all the extra food they were given.
A greater potential for error lies in incorrectly estimating the number of calories needed to maintain weight. It is very difficult to make an accurate estimate. If researchers underestimate, then some of the "extra" calories they feed the subjects are not really extra, and the subject does not gain weight. [Metabolism does not change to prevent weight gain during overfeeding. JADA 90:1556. 1990]www.diet-and-health.net
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