Nutrition- Ch 1-3 INCOMPLETE Flashcards
six major nutrients
water, lipids, carbs, proteins, minerals, vitamins
five principles of healthy diet
adequacy, balance, calorie control, moderation, variety
major types of research study
malnutrition
poor nutrition that leads to diseases and issues that come from deficiencies and imbalances
two common lifestyle habits most influential
smoking/tabacco and alcohol
nutritional genomics
study into how nutrittion influences genes
essential nutrients
body cant make self/without you will have deficiencies
calories
unit of heat
494 rule
4 cal/g of protein+ carb, 9 cal/g of fat
elemental diets
diets with a precise chemical composition that are lifesaving for people in the hospital who cannot eat ordinary food
nonnutrients
phytochemicals
nonnutrient compounds that exert biological effects on the body.
fast foods
restaurant foods that are available within minutes after customers order them—traditionally, hamburgers, french fries, and milkshakes; more recently, salads and other vegetable dishes as well. These foods may or may not meet people’s nutrient needs, depending on the selections made and on the energy allowances and nutrient needs of the eaters.
processed foods
foods subjected to any process, such as milling, alteration of texture, addition of additives, cooking, or others. Depending on the starting material and the process, a processed food may or may not be nutritious.
functional foods
a term that reflects an attempt to define as a group the foods known to possess nutrients or nonnutrients that might lend protection against diseases. However, all nutritious foods can support health in some ways;
basic foods
milk and milk products; meats and similar foods, such as fish and poultry; vegetables, including dried beans and peas; fruits; and grains. These foods are generally considered to form the basis of a nutritious diet. Also called whole foods.
enriched/fortified foods
foods to which nutrients have been added. If the starting material is a whole, basic food such as milk or whole grain, the result may be highly nutritious. If the starting material is a concentrated form of sugar or fat, the result may be less nutritious.
natural foods
a term that has no legal definition but is often used to imply wholesomeness.
nutraceutical
a term used to describe a product that has been isolated from food, often sold in pill form and believed to have medicinal effects
organic foods
understood to mean foods grown without synthetic pesticides or fertilizers. In chemistry, however, all foods are made mostly of organic (carbon-containing) compounds.
partitioned foods
foods composed of parts of whole foods, such as butter (from milk), sugar (from beets or cane), or corn oil (from corn). Partitioned foods are generally overused and provide few nutrients with many Calories.
staple foods
foods used frequently or daily, for example, rice (in East and Southeast Asia) or potatoes (in Ireland). If well chosen, these foods are nutritious.
why is variety important in a diet
One reason is that variety increases the likelihood that diet will be adequate in nutrients.Footnote In addition, some nonnutrient food components are probably important to health; some foods may be better sources of these than others. Another reason is that a monotonous diet may deliver large amounts of toxins or contaminants. Each such undesirable item in a food is diluted by all the other foods eaten with it and is even further diluted if the food is not eaten again for several days.
ABCVM of diet
adequacy, balance, calorie count, variety, moderation - five aspects of healthy diet
scientific method steps
Studies of whole populations (epidemiological studies)
correlation the simultaneous change of two factors, such as the increase in weight with increasing height (a direct or positive correlation) or the decrease in cancer incidence with increasing fibre intake (an inverse or negative correlation). A correlation between two factors suggests that one may cause the other but does not rule out the possibility that both may be caused by chance or by a third factor.
A cohort study is one in which the investigators do not manipulate the study variables of interest; instead, they monitor them over time (thus, the study is prospective in nature, a longitudinal study in which data are collected at more than one point in time). For example, such a design could be used to monitor the relationship between milk product consumption and growth in a cohort of children (often a single group of individuals with similar characteristics, for example boys or girls within a defined age range).
The type of study chosen for research depends upon what sort of information the researchers require. Studies of individuals (case studies) yield observations that may lead to possible avenues of research. A study of a man who ate gumdrops and became a famous dancer might suggest that an experiment be done to see if gumdrops contain dance-enhancing power
A case-control study (case-comparison, an epidemiological study) is one in which the investigators do not manipulate the study variables of interest. Cases are the individuals with the condition of interest, for example, some form of cancer, and the controls are cancer-free individuals and are usually matched with cases in terms of age, gender, and other characteristics. For example, such a design could be used to study the association between past whole-grain food consumption and colon cancer. These studies are most often conducted by looking back in time, which means that the outcome for the subjects is already known, thus, retrospective.
Studies in which researchers actively intervene to alter people’s eating habits (intervention studies) go a step further. In such a study, one set of subjects (the experimental group) receives a treatment, and another set (the control group) goes untreated or receives a placebo or sham treatment. If the study is a blind experiment, the subjects do not know who among the members receives the treatment and who receives the sham. A double-blind experiment is one in which neither the experimenter nor the subjects know who receives the treatment and who receives the placebo. If the two groups experience different effects, then the treatment’s effect can be pinpointed. For example, an intervention study might show that withholding gumdrops, together with other candies and confections, reduced the incidence of tooth decay in an experimental population compared with that in a control population.
Finally, laboratory studies can pinpoint the mechanisms by which nutrition acts. What is it about gumdrops that contributes to tooth decay: their size, shape, temperature, colour, ingredients? Feeding various forms of gumdrops to rats might yield the information that sugar, in a gummy carrier, promotes tooth decay. In the laboratory, using animals or plants or cells, scientists can inoculate with diseases, induce deficiencies, and experiment with variations on treatments to obtain in-depth knowledge of the process under study.
Finally, laboratory studies can pinpoint the mechanisms by which nutrition acts. What is it about gumdrops that contributes to tooth decay: their size, shape, temperature, colour, ingredients? Feeding various forms of gumdrops to rats might yield the information that sugar, in a gummy carrier, promotes tooth decay. In the laboratory, using animals or plants or cells, scientists can inoculate with diseases, induce deficiencies, and experiment with variations on treatments to obtain in-depth knowledge of the process under study.
randomized controlled trials (RCT) sometimes also referred to as clinical trials, studies in which the subjects are selected in such a way that they have an equal chance of being included in the experimental/treatment group or the control group. This type of study is considered the gold standard in research.
placebo
sham treatment often used in scientific studies; an inert harmless medication. The placebo effect is the healing effect that the act of treatment, rather than the treatment itself, often has.
laboratory studies studies that are performed under tightly controlled conditions and are designed to pinpoint causes and effects. Such studies often use animals as subjects.
intervention studies studies of populations in which observation is accompanied by experimental manipulation of some population members—for example, a study in which half of the subjects (the experimental subjects) follow diet advice to reduce fat intakes while the other half (the control subjects) do not, and both groups’ heart health is monitored.
experimental group the people or animals participating in an experiment who receive the treatment under investigation. Also called experimental subjects. See also control group and intervention studies.
epidemiological studies studies of populations; often used in nutrition to search for correlations between dietary habits and disease incidence; a first step in seeking nutrition-related causes of diseases.
control group a group of individuals who are similar in all possible respects to the group being treated in an experiment but who receive a sham treatment instead of the real one. Also called control subjects. See also experimental group and intervention studies.