Nutrition describes the processes by which all of the food a person eats are taken in and the nutrients that the body needs are absorbed. Good nutrition can help prevent disease and promote health.
The science of nutrition is dedicated to learning about foods that the human body requires at different stages of life in order to meet the nutritional needs for proper growth, as well as to maintain health and prevent disease
• For hundreds of years the ancient Greek view was that all food contained a single essential nutrient since people were able to survive on varied diets, from coastal fish-based diets to inland meat- and grain-based diets. It wasn’t until the 1700s that researchers in Europe started trying to analyze foods and realizing that a range of different food stuffs were necessary for health. In 1753 an English researcher, James Lind, linked the disease of scurvy in sailors to a lack of fresh fruits in the diet. Once lemon juice and oranges were added to the dried meat rations, sailors were able to survive for months in relative good health. In the 1800s a soldier shot in the stomach survived the gunshot wound but was left with a gaping hole in his abdomen. William Beaumont, an American doctor, observed the inner workings of the soldier’s stomach through this hole and concluded that the stomach did not grind foods mechanically but dissolved them, and foods were dissolved at different rates. Over the years these and other observations advanced the study of nutrition.
Vitamins and minerals are an important part of nutrition. Vitamins are organic substances present in food. They are required by the body in small amounts to regulate metabolism and to maintain normal growth and functioning. Minerals are vital because they are the building blocks that make up the muscles, tissues, and bones. They also are important to many life-supporting systems, such as hormones, transport of oxygen, and enzyme systems.
Before a child is even born, the nutrition they receive, via the mother, determines their health and development.
. A baby is born with a very high requirement for energy and nutrient intake per unit of body weight to provide for rapid growth. The rate of growth is the highest during the first year and declines slowly after the age of two, with a corresponding decrease in nutrient and energy requirements. During puberty, however, nutritional requirements increase sharply until this period of fast growth is completed. Adulthood begins at about the age of fourteen or fifteen for girls, and eighteen or nineteen for boys.
Maintaining a healthy diet through each stage of life is vital to positively affect current and future health, as well as the quality of life one will enjoy/
At the onset of adulthood, energy requirements usually reach a plateau that will last until one’s mid-forties, after which they begin to decline, primarily because activity levels and lean muscle mass (amount of muscle vs. body fat), which represents the BMR, decrease. It is believed that the changes in body composition and reduced lean muscle mass occur at a rate of about 5 percent per decade, and energy requirements decrease accordingly. However, these changes in body composition and decreased energy requirements can be prevented by maintaining regular physical activity, including resistance training, which helps maintain lean muscle mass and prevent deposition of excess body fat.
Older adults who are not physically active or who have poor nutritional practices will have a decline in BMR, a change in body composition, an increasing percentage of body fat, and a decrease in lean body muscle mass. In addition, they will show the signs of aging and will be more likely to develop degenerative diseases.
Many older adults need to take medications to control the advance of diabetes, hypertension , and cardiovascular disease. Medications can interfere with proper nutrition, however, as they affect appetite, the digestion and absorption of nutrients, and normal function of the digestive system.
Every day we are bombarded with nutrition and health messages and a seemingly endless array of concerns about lifestyle and diet. Healthy eating and a healthful way of life are important to how we look, feel and how much we enjoy life.
The right lifestyle decisions, with a routine of good food and regular exercise, can help us make the most of what life has to offer. Making smart food choices early in life and through adulthood can also help reduce the risk of certain conditions such as obesity, heart disease, hypertension, diabetes, certain cancers and osteoporosis
Factors of a healthy diet
Enjoy the wide variety of foods
We need more than 40 different nutrients for good health and no single food can supply them all. That’s why consumption of a wide variety of foods (including fruits, vegetables, cereals and grains, meats, fish and poultry, dairy products and fats and oils), is necessary for good health and any food can be enjoyed as part of a healthy diet.
Eat regularly
Eating is one of the life’s great pleasures and its important to take time to stop, relax and enjoy mealtimes and snacks.
Breakfast is particularly important as it helps kick-start the body by supplying energy after the all-night fast.
Balance and moderation
Balancing your food intake means getting enough, but not too much, of each type of nutrient.
Maintain a healthy body weight and feel good
A healthy weight varies between individuals and depends on many factors including gender, height, age and hereditary. Physical activity and avoiding excess eating is a good way of maintaining a healthy body weight.
Eat a lot of fruits and vegetables
Eating at least five servings of fruits and vegetables daily is associated with a reduced risk in degenerative diseases like coronary disease cancer and diabetes.
Base the diet on foods rich in carbohydrates
Although the body treats all carbohydrates in the same way regardless of their source, carbohydrates are often. Complex carbohydrates that come from plants are called starch and fibres, and these are found for example in cereal grains, vegetables, breads, seeds, legumes and beans. Simple carbohydrates (sometimes called simple sugars) are found for example in table sugar, fruits, sweets, jams, soft drinks, fruit juices, honey, jellies and syrups.
Drink plenty of fluids
Adults need to drink at least 1.5 litres of fluid daily, even more if its hot or they are physically active.
Fats in moderation
Fat is a nutrient in food that is essential for good health.
Too much fat however, especially saturated fats, can lead to adverse health effects such as overweight and high cholesterol and increase the risk of heart disease and some cancers.
Balance the salt intake
Salt (NaCl) is made up of sodium and chloride.
For most people, any excess sodium passes straight through the body however in some people it can increase blood pressure.
Reducing the amount of salt in the diet of those who are sensitive to salt may reduce the risk of high blood pressure.