Overview of the Principles of Nutrition

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To help you get started with this paper, I've included a couple points and references for each question. Lastly, some of the references are included as websites, others are pdfs, and others are citations that you can put into pubmed or Google Scholar to receive the whole article.

1. ID factors that influence what people eat, and learn how to evaluate nutrient adequacy of a diet
- when choosing what to eat, people take into account some or all of the following factors: taste/enjoyability, nutrition, convenience (how fast would it be to get), and cost
- the importance of the varying factors changes from person to person (eg. impoverished people might value cost more, busy people may value convenience, new mothers may value nutrition)
- the nutritional adequacy of a diet can be evaluated by a number of measures; more in-depth medical measures include blood tests to examine nutrient levels, while quicker methods include simply ensuring variety within the diet (variety among the food groups), containing plenty of fruits and vegetables, or even the simple rule of ensuring variety of colours at each meal (at least four different colours)
- food guidelines, such as the Canada Food Guide is often sufficient
- often, the more in-depth method is only necessary when a person is or becomes ill, and the normal dietary guidelines need changing or supplementation for them individually
References: Guthrie, H. A. & Scheer, J. C. (1981). Validity of a dietary score for assessing nutrient adequacy. Journal of American Dietetic Association 78(3):240-245.

2. apply knowledge of the six classes of nutrients to daily diet, recipe modification, etc.
- each of the classes are vital to the diet and should appear in the diet in specific proportions or amounts, as follows: water (should have about 2 L a day), carbohydrates (40-50% of calories), protein (25-35% of calories), fat (20-30% of calories), vitamins, and minerals
- the amount of vitamins and minerals depends on the specific vitamin and mineral
- some vitamins and minerals can be taken in excess, while some become toxic
- in general, malnutrition involves an imbalance where any of these nutrients is lacking or taken in excess
- at each meal, these nutrients groups should be taken into account, and recipes could be modified to increase these groups (eg. put raisins or cranberries in cookie recipes to increase vitamins and minerals, even though it does little to affect caloric intake)
References: Snyder, M. P., Story, M. & Trenkner, L. L. (1992). Reducing fat and sodium in school lunch programs: the LUNCHPOWER! Interventional Study. Journal of American Dietetic Association 92(9):1087-1091.

3. demonstrate awareness of personal, cultural, economic, and physiological factors that influence individual differences in dietary practices
- as I mentioned in the first question, in choosing which foods to eat, different factors are involved, including cost. Thus, in poorer economies, there may not be as many food options.
- physiological factors include the fact that some people require special diets due to nutritional needs (people with the condition PKU require a special diet that eliminates fish and chicken and cheese and is low in starchy carbs)
- cultural factors simply refers to the fact that people tend to eat similar to how they were raised and in the culture they are surrounded, partly due to convenience, but also due to emotional connection (for example, somebody raised vegetarian will probably continue to eat vegetarian)
References: Axelson, M. L. (1986). The impact of culture on food-related behaviour. Annual Review of Nutrition 6:345-363.

4. describe the process by which scientists uncover nutrition facts
- well, this is a very complicated question, and there are many aspects and experiments that scientists can use to uncover nutrition facts
- to study how nutrients are broken down, scientists must use molecular biology
- to study the effect different diets have on health, scientists can feed animal models particular diets, perform short studies feeding human subjects particular diets, or collect data about both people's health and their diet
- to study nutritional info in a population, scientists can use surveys to examine the eating habits of a particular diet
- thus, quantitative and qualitative data can be collected, both in vitro and in vivo to uncover nutrition facts

5. distinguish valid nutritional information from misinformation
- people should be careful about where they access nutritional information
- the food industry pays a lot to encourage people to eat their products, including paying for advertising and even buying out politicians (eg. the corn industry and beef industry are both large political players in the United States); the studies done by and information produced by the food industry may be heavily biased and therefore be misinformation
- in general, advertising aims to manipulate people in order to increase revenue, while valid nutritional information can be found in sources that aim to educate and inform
- articles in magazines tend to vary largely based on the magazine, and the reader should always look at who is writing the article
- people can find the nutritional info of the food they eat on many of the labels, and can find good tips about nutrition from their doctors or from scholarly articles that are not funded by the food industry
References: Ross, R. P., Campbell, T., Huston-Stein, A. & Wright, J. C. (1981). Nutritional ...