5.Check Your Head
Surveys and measurements of student height and weight were completed in school classrooms during the school year. Statistically speaking, it is clearly best to keep the same sample from one collection to the next, for this helps to reduce sample variance and to estimate the share of variance due to the intervention or to outside phenomena. Several types of low-cost nutritious recipes are described in the book after thoroughly testing these foods in the community for acceptability and tolerance. And yet, so many of them die. National Basketball Association all-time scoring leaders The implementation indicators that were adopted focused on the number and quality of educational materials produced, the number of training workshops held and teachers thus recruited, and the number of promotion campaigns carried out, associations set up and situation reports produced by those in charge throughout implementation of the programme, etc. Nearly participants completed year follow-up surveys assessing weight status, weight-related behaviors, and potential correlates of these outcomes.
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Dietary fiber is a carbohydrate that is incompletely absorbed in humans and in some animals. Like all carbohydrates, when it is metabolized it can produce four Calories kilocalories of energy per gram.
However, in most circumstances it accounts for less than that because of its limited absorption and digestibility. Dietary fiber consists mainly of cellulose, a large carbohydrate polymer which is indigestible as humans do not have the required enzymes to disassemble it.
There are two subcategories: Whole grains, fruits especially plums , prunes , and figs , and vegetables are good sources of dietary fiber. There are many health benefits of a high-fiber diet.
Dietary fiber helps reduce the chance of gastrointestinal problems such as constipation and diarrhea by increasing the weight and size of stool and softening it. Insoluble fiber, found in whole wheat flour , nuts and vegetables, especially stimulates peristalsis ;— the rhythmic muscular contractions of the intestines, which move digest along the digestive tract. Soluble fiber, found in oats, peas, beans, and many fruits, dissolves in water in the intestinal tract to produce a gel that slows the movement of food through the intestines.
This may help lower blood glucose levels because it can slow the absorption of sugar. Additionally, fiber, perhaps especially that from whole grains, is thought to possibly help lessen insulin spikes, and therefore reduce the risk of type 2 diabetes.
The link between increased fiber consumption and a decreased risk of colorectal cancer is still uncertain. A molecule of dietary fat typically consists of several fatty acids containing long chains of carbon and hydrogen atoms , bonded to a glycerol. They are typically found as triglycerides three fatty acids attached to one glycerol backbone. Fats may be classified as saturated or unsaturated depending on the detailed structure of the fatty acids involved.
Saturated fats have all of the carbon atoms in their fatty acid chains bonded to hydrogen atoms, whereas unsaturated fats have some of these carbon atoms double-bonded , so their molecules have relatively fewer hydrogen atoms than a saturated fatty acid of the same length.
Unsaturated fats may be further classified as monounsaturated one double-bond or polyunsaturated many double-bonds. Furthermore, depending on the location of the double-bond in the fatty acid chain, unsaturated fatty acids are classified as omega-3 or omega-6 fatty acids.
Trans fats are a type of unsaturated fat with trans -isomer bonds; these are rare in nature and in foods from natural sources; they are typically created in an industrial process called partial hydrogenation. There are nine kilocalories in each gram of fat.
Fatty acids such as conjugated linoleic acid , catalpic acid, eleostearic acid and punicic acid , in addition to providing energy, represent potent immune modulatory molecules. Saturated fats typically from animal sources have been a staple in many world cultures for millennia.
Saturated and some trans fats are typically solid at room temperature such as butter or lard , while unsaturated fats are typically liquids such as olive oil or flaxseed oil.
Trans fats are very rare in nature, and have been shown to be highly detrimental to human health, but have properties useful in the food processing industry, such as rancidity resistance. Most fatty acids are non-essential, meaning the body can produce them as needed, generally from other fatty acids and always by expending energy to do so.
However, in humans, at least two fatty acids are essential and must be included in the diet. An appropriate balance of essential fatty acids— omega-3 and omega-6 fatty acids —seems also important for health, although definitive experimental demonstration has been elusive.
Both of these "omega" long-chain polyunsaturated fatty acids are substrates for a class of eicosanoids known as prostaglandins , which have roles throughout the human body. They are hormones , in some respects. The omega-3 eicosapentaenoic acid EPA , which can be made in the human body from the omega-3 essential fatty acid alpha-linolenic acid ALA , or taken in through marine food sources, serves as a building block for series 3 prostaglandins e.
The omega-6 dihomo-gamma-linolenic acid DGLA serves as a building block for series 1 prostaglandins e. An appropriately balanced intake of omega-3 and omega-6 partly determines the relative production of different prostaglandins, which is one reason why a balance between omega-3 and omega-6 is believed important for cardiovascular health.
In industrialized societies, people typically consume large amounts of processed vegetable oils, which have reduced amounts of the essential fatty acids along with too much of omega-6 fatty acids relative to omega-3 fatty acids.
Moreover, the conversion desaturation of DGLA to AA is controlled by the enzyme deltadesaturase , which in turn is controlled by hormones such as insulin up-regulation and glucagon down-regulation. The amount and type of carbohydrates consumed, along with some types of amino acid, can influence processes involving insulin, glucagon, and other hormones; therefore, the ratio of omega-3 versus omega-6 has wide effects on general health, and specific effects on immune function and inflammation , and mitosis i.
Proteins are structural materials in much of the animal body e. They also form the enzymes that control chemical reactions throughout the body. Each protein molecule is composed of amino acids , which are characterized by inclusion of nitrogen and sometimes sulphur these components are responsible for the distinctive smell of burning protein, such as the keratin in hair.
The body requires amino acids to produce new proteins protein retention and to replace damaged proteins maintenance. As there is no protein or amino acid storage provision, amino acids must be present in the diet.
Excess amino acids are discarded, typically in the urine. For all animals, some amino acids are essential an animal cannot produce them internally and some are non-essential the animal can produce them from other nitrogen-containing compounds.
About twenty amino acids are found in the human body, and about ten of these are essential and, therefore, must be included in the diet. A diet that contains adequate amounts of amino acids especially those that are essential is particularly important in some situations: A complete protein source contains all the essential amino acids; an incomplete protein source lacks one or more of the essential amino acids.
It is possible with protein combinations of two incomplete protein sources e. However, complementary sources of protein do not need to be eaten at the same meal to be used together by the body. Water is excreted from the body in multiple forms; including urine and feces , sweating , and by water vapour in the exhaled breath. Therefore, it is necessary to adequately rehydrate to replace lost fluids.
Early recommendations for the quantity of water required for maintenance of good health suggested that 6—8 glasses of water daily is the minimum to maintain proper hydration. Most of this quantity is contained in prepared foods. For healthful hydration, the current EFSA guidelines recommend total water intakes of 2.
These reference values include water from drinking water, other beverages, and from food. The EFSA panel also determined intakes for different populations. Recommended intake volumes in the elderly are the same as for adults as despite lower energy consumption, the water requirement of this group is increased due to a reduction in renal concentrating capacity.
Dehydration and over-hydration - too little and too much water, respectively - can have harmful consequences. Drinking too much water is one of the possible causes of hyponatremia , i. Pure ethanol provides 7 calories per gram.
For distilled spirits , a standard serving in the United States is 1. A 5 ounce serving of wine contains to calories. A 12 ounce serving of beer contains 95 to calories. Alcoholic beverages are considered empty calorie foods because other than calories, these contribute no essential nutrients.
The micronutrients are minerals , vitamins , and others. Dietary minerals are inorganic chemical elements required by living organisms,  other than the four elements carbon , hydrogen , nitrogen , and oxygen that are present in nearly all organic molecules. The term "mineral" is archaic, since the intent is to describe simply the less common elements in the diet. Some are heavier than the four just mentioned, including several metals , which often occur as ions in the body.
Some dietitians recommend that these be supplied from foods in which they occur naturally, or at least as complex compounds, or sometimes even from natural inorganic sources such as calcium carbonate from ground oyster shells. Some minerals are absorbed much more readily in the ionic forms found in such sources. On the other hand, minerals are often artificially added to the diet as supplements; the most famous is likely iodine in iodized salt which prevents goiter.
Many elements are essential in relative quantity; they are usually called "bulk minerals". Some are structural, but many play a role as electrolytes. Many elements are required in trace amounts, usually because they play a catalytic role in enzymes.
Vitamins are essential nutrients,  necessary in the diet for good health. Vitamin D is an exception, as it can be synthesized in the skin in the presence of UVB radiation , and many animal species can synthesize vitamin C. Vitamin deficiencies may result in disease conditions, including goitre , scurvy , osteoporosis , impaired immune system, disorders of cell metabolism, certain forms of cancer, symptoms of premature aging, and poor psychological health , among many others. Phytochemicals such as polyphenols are compounds produced naturally in plants phyto means "plant" in Greek.
In general, the term is used to refer to compounds which do not appear to be nutritionally essential and yet may have positive impacts on health. To date, there is no conclusive evidence in humans that polyphenols or other non-nutrient compounds from plants have health benefit effects.
While initial studies sought to reveal if nutrient antioxidant supplements might promote health, one meta-analysis concluded that supplementation with vitamins A and E and beta-carotene did not convey any benefits and may in fact increase risk of death.
Vitamin C and selenium supplements did not impact mortality rate. Health effects of non-nutrient phytochemicals such as polyphenols were not assessed in this review. Animal intestines contain a large population of gut flora. In humans, the four dominant phyla are Firmicutes , Bacteroidetes , Actinobacteria , and Proteobacteria. Bacteria in the large intestine perform many important functions for humans, including breaking down and aiding in the absorption of fermentable fiber, stimulating cell growth, repressing the growth of harmful bacteria, training the immune system to respond only to pathogens, producing vitamin B 12 , and defending against some infectious diseases.
There is not yet a scientific consensus as to health benefits accruing from probiotics or prebiotics. Carnivore and herbivore diets are contrasting, with basic nitrogen and carbon proportions vary for their particular foods. Many herbivores rely on bacterial fermentation to create digestible nutrients from indigestible plant cellulose, while obligate carnivores must eat animal meats to obtain certain vitamins or nutrients their bodies cannot otherwise synthesize.
Plant nutrition is the study of the chemical elements that are necessary for plant growth. Some elements are directly involved in plant metabolism. However, this principle does not account for the so-called beneficial elements, whose presence, while not required, has clear positive effects on plant growth.
A nutrient that is able to limit plant growth according to Liebig's law of the minimum is considered an essential plant nutrient if the plant cannot complete its full life cycle without it. There are 16 essential plant soil nutrients, besides the three major elemental nutrients carbon and oxygen that are obtained by photosynthetic plants from carbon dioxide in air, and hydrogen , which is obtained from water.
Plants uptake essential elements from the soil through their roots and from the air consisting of mainly nitrogen and oxygen through their leaves.
Green plants obtain their carbohydrate supply from the carbon dioxide in the air by the process of photosynthesis. Carbon and oxygen are absorbed from the air, while other nutrients are absorbed from the soil. These hydrogen ions displace cations attached to negatively charged soil particles so that the cations are available for uptake by the root. In the leaves, stomata open to take in carbon dioxide and expel oxygen.
The carbon dioxide molecules are used as the carbon source in photosynthesis. Although nitrogen is plentiful in the Earth's atmosphere, very few plants can use this directly. Most plants, therefore, require nitrogen compounds to be present in the soil in which they grow. This is made possible by the fact that largely inert atmospheric nitrogen is changed in a nitrogen fixation process to biologically usable forms in the soil by bacteria.
Plant nutrition is a difficult subject to understand completely, partially because of the variation between different plants and even between different species or individuals of a given clone. Elements present at low levels may cause deficiency symptoms, and toxicity is possible at levels that are too high. Furthermore, deficiency of one element may present as symptoms of toxicity from another element, and vice versa. Canada's Food Guide is an example of a government-run nutrition program.
Produced by Health Canada , the guide advises food quantities, provides education on balanced nutrition, and promotes physical activity in accordance with government-mandated nutrient needs. Like other nutrition programs around the world, Canada's Food Guide divides nutrition into four main food groups: Dietary and physical activity guidelines from the USDA are presented in the concept of MyPlate , which superseded the food pyramid , which replaced the Four Food Groups.
Department of Health and Human Services provides a sample week-long menu that fulfills the nutritional recommendations of the government. Governmental organisations have been working on nutrition literacy interventions in non-primary health care settings to address the nutrition information problem in the U. The FNP has developed a series of tools to help families participating in the Food Stamp Program stretch their food dollar and form healthful eating habits including nutrition education.
It is designed to assist limited-resource audiences in acquiring the knowledge, skills, attitudes, and changed behavior necessary for nutritionally sound diets, and to contribute to their personal development and the improvement of the total family diet and nutritional well-being.
Launched in , this program promotes lifelong healthful eating patterns and physically active lifestyles for children and their families.
It is an interactive educational program designed to help prevent childhood obesity through classroom activities that teach children healthful eating habits and physical exercise. Nutrition is taught in schools in many countries. In England and Wales , the Personal and Social Education and Food Technology curricula include nutrition, stressing the importance of a balanced diet and teaching how to read nutrition labels on packaging.
In many schools, a Nutrition class will fall within the Family and Consumer Science or Health departments. In some American schools, students are required to take a certain number of FCS or Health related classes. Nutrition is offered at many schools, and, if it is not a class of its own, nutrition is included in other FCS or Health classes such as: In many Nutrition classes, students learn about the food groups, the food pyramid, Daily Recommended Allowances, calories, vitamins, minerals, malnutrition, physical activity, healthful food choices, portion sizes, and how to live a healthy life.
In the US, Registered dietitian nutritionists RDs or RDNs  are health professionals qualified to provide safe, evidence-based dietary advice which includes a review of what is eaten, a thorough review of nutritional health, and a personalized nutritional treatment plan. They also provide preventive and therapeutic programs at work places, schools and similar institutions.
Certified Clinical Nutritionists or CCNs, are trained health professionals who also offer dietary advice on the role of nutrition in chronic disease, including possible prevention or remediation by addressing nutritional deficiencies before resorting to drugs. These Board Certified Nutritionists typically specialize in obesity and chronic disease. In order to become board certified, potential CNS candidate must pass an examination, much like Registered Dieticians. This exam covers specific domains within the health sphere including; Clinical Intervention and Human Health.
The study found that health literacy increases with education and people living below the level of poverty have lower health literacy than those above it. Another study examining the health and nutrition literacy status of residents of the lower Mississippi Delta found that 52 percent of participants had a high likelihood of limited literacy skills. For example, only 12 percent of study participants identified the My Pyramid graphic two years after it had been launched by the USDA.
The study also found significant relationships between nutrition literacy and income level and nutrition literacy and educational attainment  further delineating priorities for the region.
Among these problems are the lack of information about food choices, a lack of understanding of nutritional information and its application to individual circumstances, limited or difficult access to healthful foods, and a range of cultural influences and socioeconomic constraints such as low levels of education and high levels of poverty that decrease opportunities for healthful eating and living. Iron fortification programs have been credited with improving the iron status of millions of women, infants, and children.
Fortification of foods with iron does not significantly affect zinc absorption. However, large amounts of supplemental iron greater than 25 mg might decrease zinc absorption [ 2 , 78 ]. Taking iron supplements between meals helps decrease its effect on zinc absorption [ 78 ]. High zinc intakes can inhibit copper absorption, sometimes producing copper deficiency and associated anemia [ 79 , 80 ].
For this reason, dietary supplement formulations containing high levels of zinc, such as the one used in the AREDS study [ 72 ], sometimes contain copper. Zinc toxicity can occur in both acute and chronic forms. Acute adverse effects of high zinc intake include nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches [ 2 ].
One case report cited severe nausea and vomiting within 30 minutes of ingesting 4 g of zinc gluconate mg elemental zinc [ 81 ]. Intakes of — mg of zinc per day have been associated with such chronic effects as low copper status, altered iron function, reduced immune function, and reduced levels of high-density lipoproteins [ 82 ]. Long-term intakes above the UL increase the risk of adverse health effects [ 2 ].
The ULs do not apply to individuals receiving zinc for medical treatment, but such individuals should be under the care of a physician who monitors them for adverse health effects. Zinc supplements have the potential to interact with several types of medications. A few examples are provided below. Individuals taking these medications on a regular basis should discuss their zinc intakes with their healthcare providers.
Taking the antibiotic at least 2 hours before or 4—6 hours after taking a zinc supplement minimizes this interaction [ 86 ]. Zinc can reduce the absorption and action of penicillamine, a drug used to treat rheumatoid arthritis [ 87 ]. To minimize this interaction, individuals should take zinc supplements at least 2 hours before or after taking penicillamine [ 85 ].
Prolonged use of thiazide diuretics could deplete zinc tissue levels, so clinicians should monitor zinc status in patients taking these medications. The federal government's Dietary Guidelines for Americans notes that "Nutritional needs should be met primarily from foods. Foods in nutrient-dense forms contain essential vitamins and minerals and also dietary fiber and other naturally occurring substances that may have positive health effects.
In some cases, fortified foods and dietary supplements may be useful in providing one or more nutrients that otherwise may be consumed in less-than-recommended amounts. For more information about building a healthy diet, refer to the Dietary Guidelines for Americans and the U. Department of Agriculture's MyPlate. This fact sheet by the Office of Dietary Supplements ODS provides information that should not take the place of medical advice. We encourage you to talk to your healthcare providers doctor, registered dietitian, pharmacist, etc.
Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice. March 2, History of changes to this fact sheet. Strengthening Knowledge and Understanding of Dietary Supplements.
Zinc Fact Sheet for Health Professionals. J Lab Clin Med ; National Academy Press, Mild human zinc deficiency produces an imbalance between cell-mediated and humoral immunity. Zinc deficiency and taste disorders. Zinc in the fetus and newborn. Acta Paediatr Scand Suppl ; Zinc, human diseases and aging. Zinc requirements and the risks and benefits of zinc supplementation. J Trace Elem Med Biol ; Proc Assoc Am Physicians ; Zinc and the immune system.
Proc Nutr Soc ; Department of Agriculture, Agricultural Research Service. Nutrient Data Laboratory Home Page, http: Eur J Clin Nutr ;51 1 Suppl: Phytate and zinc bioavailability. Int J Food Sci Nutr ; Anosmia after intranasal zinc gluconate use. Am J Rhinol ; Intranasal zinc and anosmia: Food and Drug Administration. Nat Clin Pract Neurol. Dietary intake of vitamins, minerals, and fiber of persons ages 2 months and over in the United States: Advance data from vital and health statistics no National Center for Health Statistics.
Government Printing Office, Mineral intakes of elderly adult supplement and non-supplement users in the third national health and nutrition examination survey. Dynamics of Poverty and Food Sufficiency. Food Assistance and Nutrition Report Number 36, Department of Agriculture, Economic Research Service.
Dietary intakes and serum nutrients differ between adults from food-insufficient and food-sufficient families: Met Ions Biol Syst ; Images in clinical medicine. N Engl J Med ; Zinc in Human Biology. Modern Nutrition in Health and Disease, 10th ed. Krasovec M, Frenk E. Acrodermatitis enteropathica secondary to Crohn's disease. Effect of marginal zinc deficiency on human growth and development. J Trop Pediatr ; J Am Coll Nutr ; Bioavailability of iron, zinc, and other trace minerals from vegetarian diets.
Am J Clin Nutr ;78 3 Suppl: Clinical and laboratory assessment of zinc deficiency in Dutch children. Biol Trace Elem Res ; Zinc deficiency in women, infants and children. The value of methods to determine zinc deficiency in patients with Crohn's disease. Scand J Gastroenterol ; Zinc absorption in inflammatory bowel disease.
J Am Diet Assoc ; Potential contribution of maternal zinc supplementation during pregnancy to maternal and child survival. Am J Clin Nutr ;68 2 Suppl: Zinc supplementation during lactation.
Zinc supplementation and children's growth: Bibl Nutr Dieta ; Individuals who are deaf, hard of hearing or have speech disabilities may contact USDA through the Federal Relay Service at Additionally, program information may be made available in languages other than English. To request a copy of the complaint form, call Submit your completed form or letter to USDA by:. Submit your completed form or letter to USDA by: This institution is an equal opportunity provider.
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