what's the frequency of the letter "o" in:
introduction
traditionally, salt (sodium chloride) has been viewed as a food preservative that enhances human health by killing or limiting growth of foodborne pathogens and spoilage organisms. however, in recent decades, with increasing consumption of many different processed foods containing high levels of sodium, the perception of dietary salt has evolved to a point where it is now considered, by some, to be a potential health threat. the inst. of medicine of the natl. academy of sciences has established adequate daily intakes (ais) for sodium and potassium and a tolerable upper intake level (ul) for sodium, based on its effects on blood pressure (table 1; iom 2004). persons with a greater risk for hypertension (adults who are black, over 40 y old, or already have hypertension or prehypertension) have been urged to consume no more than the ai level of sodium each day (cdcp 2009).
natural sodium levels in foods generally account for only about 10% of dietary intake. most dietary sodium is ingested in the form of sodium chloride (table salt). in european and north american countries, approximately 5% to 10% of intake is due to the discretionary addition of salt at the table and during cooking, whereas processed foods and foods served in restaurants are estimated to contribute over 75% of dietary sodium (mattes and donnelly 1991). a recent study in denmark used lithium-tagged salt to replace normal salt used by 87 people in the home for a 10-d period. analyses of 24-h urine samples revealed that 8.7% (for women) and 10.2% (for men) of salt consumed was added to foods by the subjects. approximately, 90% of sodium chloride intake came from sodium naturally present in foods or added to processed and manufactured foods (andersen and others 2009). in asian countries, salt added in home cooking and at the table accounts for an estimated 72% to 76% of dietary intake. soy sauce, miso, salted vegetables, fruits, and fish contribute significantly to dietary sodium (brown and others 2009).
in addition to obviously salty foods, such as certain snacks, sodium content is quite high in many packaged dinners, soups, sauces, and processed meats and cheeses. cured meats, for example, are estimated to contribute 20.5% of the sodium in the irish diet (desmond 2007). although salt levels in breads and cereals are relatively low, people generally consume more of this food group and therefore breads and cereals contribute an estimated 35% to 50% to sodium intake in some countries (beer-borst and others 2009; brown and others 2009; thomson 2009).
some foods, for example, 8 oz of some commercial tomato soups and 4 oz of some types of pizza, may contain nearly an entire day's adequate intake of sodium. this has led the american public health assn. and the american medical assn. to call for a 50% reduction in sodium in processed and restaurant foods over a 10-y period. revocation of the generally recognized as safe (gras) status of salt has also been proposed to make food processors justify the amount of salt added to foods (dickinson and havas 2007). fda held a hearing on this proposal and on possible changes to labeling regulations in november 2007.
sodium reduction is also a topic of intense international interest. who (world health organization), as part of its global strategy on diet, physical activity and health, organized a forum and technical meeting in 2006 to review and discuss the link between high salt consumption and health. various initiatives to reduce population-wide salt intake and the cost and effectiveness of these programs were evaluated (who 2007). an international organization of experts from 80 countries, wash (world action on salt and health), was established in 2005 to publicize adverse effects of sodium chloride on health and to work with governments and industry to reduce salt levels in catered, restaurant, and processed foods, as well as salt added during cooking and at the table (). several countries, including japan, finland, australia, and the u.k., have developed strategies for significantly reducing the sodium chloride content in many processed foods and encouraging a decrease in discretionary salt use (cobcroft and others 2008; he and macgregor 2009).
it is critical to note that efforts to reduce salt in processed foods must be balanced with the original purpose of salting many foods—prevention of the growth of pathogenic and spoilage organisms. salt- and sodium-containing ingredients also serve other functions in foods including producing and maintaining characteristic textures, controlling yeast growth during breadmaking, and masking bitter tastes. when salt and sodium levels in foods are reduced, then other preservatives may be needed to ensure food safety and flavoring agents, other additives, and different processing techniques may be required to preserve quality and texture of foods.
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The text includes three hundred and forty-seven "o"s in total.
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