Nutrition

ThiQar college of MedicineFamily & Community medicine dept. Nutrition Lecture 1Third stage by:Dr. Muslim N. SaeedThursday ,December 17th,2015

Course objectives

NUTRITION AND HEALTH

Why do we study Nutrition & Health??

Food has been considered important for human being, in terms of health and disease, through its association with infection, immunity, fertility, maternal and child health and family health.

How Does Nutrition Contribute to Health?

Proper nutrition can help us improve our health, prevent certain diseases, achieve and maintain a desirable weight, and maintain our energy and vitality. When you consider that most people eat on average three meals per day, this results in almost 11,000 opportunities during a 10-year period to affect our health through nutrition.


2. More recently, interests on the role of dietary factors in the pathogenesis of non-communicable diseases NCDs (such as CHD, DM and cancer) have been developed.



3. Moving from the labs to epidemiology, it has been proved that nutritional health problems are multifactorial; education, demography, agriculture and rural development.

Definitions

Food:
Products derived from plants or animals that can be taken into the body to give it energy for the maintenance of life, growth and repair of tissues.

Diet:

The foods and beverages a person eats and drinks.

Nutrition:

The science of foods and nutrients and other substances they contain, and of their actions within the body (including ingestion, digestion, absorption, transport, metabolism, and excretion). A broader definition includes the social, economic, cultural, and psychological implications of food and eating.

Dietetics:

The practical applications of the principles of nutritionIt includes “the planning of meals for the well and the sick”


Classification of food:


Classification by origin Classification by chemical composition Classification by predominant function

Classification by origin:

Foods of animal origin Foods of vegetable origin

Classification by predominant function:

Body-building foods: e.g. milk, meat, poultry, fish, egg, pulses ...etc. Energy giving foods: e.g. cereals, sugars, fats and oils. Protective foods: e.g. vegetables, fruits ... etc.

Nutrients:

Organic and inorganic complexes contained in food. -Each nutrient has specific functions in the body ..

Macronutrients:

-Proteins (60 gm/d). -Fats (15 gm/d). -Carbohydrates (100 gm/d).

Micronutrients:

Vitamins and minerals, (milligrams and micrograms daily).

Food choices

People decide what to eat, when to eat, and even whether to eat in highly personal ways, often based on behavioral or social motives rather than on an awareness of nutrition’s importance to health. Many different food choices can support good health , and an understanding of nutrition helps you make sensible selections more often.

Personal Preference

The number one reason people choosefoods is taste—they like certain flavors.Two widely shared preferences are for thesweetness of sugar and the savoriness of salt. Liking high-fat foods also appears to be a universally common preference. Other preferences might be for the hot peppers. Some research suggests that genetics may influence people’s food preferences.

Habit

People sometimes select foods out of habit. They eat cereal every morning, for example, simply because they have always eaten cereal for breakfast. Eating a familiar food and not having to make any decisions can be comforting.

Ethnic Heritage or Tradition

Among the strongest influences on food choices are ethnic heritage and tradition.People eat the foods they grew up eating. Every country, and in fact every region ofa country, has its own typical foods and ways of combining them into meals. The “American diet” includes many ethnic foods from various countries, all adding variety to the diet.

Social Interactions

Most people enjoy companionship while eating. It’s fun to go out with friends for pizza or ice cream. Meals are social events, and sharing food is part of hospitality. Social customs invite people to accept food or drink offered by a host or shared by a group.


Availability, Convenience, and Economy
People eat foods that are accessible,quick and easy to prepare, and within their financial means. Today’s consumersvalue convenience and are willing to spend more than half of their food budget onmeals that require little, if any, further preparation. They frequently eat out, bring home ready-to-eat meals, or have food delivered.

Positive and Negative Associations

People tend to like particular foods associated with happy occasions—such as hot dogs at ball games or cake and ice cream at birthday parties. By the same token, people can develop aversions and dislike foods that they ate when they felt sick or that were forced on them. By using foods as rewards or punishments, parents may inadvertently teach their children to like and dislike certain foods.

Emotional Comfort

Some people cannot eat when they are emotionally upset.Others may eat in response to a variety of emotional stimuli—for example, to relieve depression or to calm anxiety. A depressed person may choose to eat rather than to call a friend. A person who has returned home from an exciting evening out may unwind with a late-night snack.

These people may find emotionalcomfort, in part, because foods can influence the brain’s chemistry and the mind’s response. Carbohydrates and alcohol, for example, tend to calm, whereas proteins and caffeine are more likely to activate. Eating in response to emotions can easily lead to overeating and obesity, but it may be appropriate at times. For example, sharing food at times of bereavement.

Values

Food choices may reflect people’s religious beliefs, political views, or environmental concerns. For example, many Christians forgo meat during Lent (the period prior to Easter),and Muslims fast between sunrise and sunset during Ramadan (the ninth month of the Islamic calendar).

Body Weight and Image

Sometimes people select certain foods and supplements that they believe will improve their physical appearance and avoid those they believe might be detrimental. Such decisions can be beneficial when based on sound nutrition and fitness knowledge, but decisions based on fads or carried to extremes undermine good health, as pointed out in later discussions of eating disorders

Nutrition and Health Benefits

Many consumers make food choices that will benefit health. Food manufacturers and restaurant chefs have responded to scientific findings linking health with nutrition by offering an abundant selection of health-promoting foods and beverages.



functional foods: foods that contain physiologically active compounds that provide health benefits beyond their nutrient contributions,as oatmeal or tomatoes. Phyto-chemicals: non nutrient compounds found in plant derived foods that have biological activity in the body. e.g of these functional foods include orange juice fortified with calcium to help build strong bones and margarine made with a plant sterol that lowers blood cholesterol.

THANK YOU