Full of Flavor – and Salt
Many Local Variants
“The Vietnamese favor Nuoc Mam, a strong fish ketchup rich in amino acids, salts and phosphorus which compensates for the low nutriti9onal value of the rice.” — Miriam Ferrari 
Fish ketchup, Signora? Rich in amino acids? Maybe, but certainly rich in salt. And how about the low nutritional value of the rice? Some of these things may have been lost in translation and only the editors at Mondadori will ever know the whole story..
In Southeast Asia, the chief salter is a sauce made from fermented fish, commonly known as Patis in the Phlippines, and Ngoc Mam in Vietnam. In Thailand, it is commonly known as Nam Pla.
Actually, Fish Sauce is used in a wider area of the Pacific Rim, including Cambodia, Laos and Burma.
Most of the societies which use Fish Sauce as a main cooking ingredient also use Soy Sauce as well.
Why Use It? Fish Sauce is said to provide the taste sensation called umami, which is enough reason for its popularity in the Pacific Rim.
Fish Sauce Zone: So the Fish Sauce Zone within the Pacific Rim basically comp[rises Burma, Cambodia, Laos, Thailand and Vietnam, as well as the Philippines.
The Southeast Asian versions of Fish Sauce have parallels in similar fish extracts used in the cuisines of Korea and Japan and in some preparations used in the ancient Mediterranean world.
Nutritional Aspects: Some nutritional analysis is available for several of the many varieties of this sauce. In one study, a serving of Thai Fish Sauce is estimated to be about 1 tablespoon or 15 grams, and that amount contains over 1,000 milligrams of sodium, and small traces of Vitamin A and C. All the Fish Sauces are very high in sodium and as a result would have to be used with care by persons concerned about sodium levels. 
Brands: There are many different brands of Fish Sauce and many people have definite opinions on which is best. The Tiparos brand from Thailand is often mentioned by Thai cooks and others from the region as one of the best brands. 
In the Kitchen: Fish Sauce is essentially shelf stable once opened. If you are cooking Southeast Asian dishes, there is not much you specially need to do regarding Fish Sauce, other than to keep a bottle on hand and use as directed in recipes.
For persons on reduced salt intake, Fish Sauce should be enjoyed in moderation, as a typical serving contains over a gram of sodium, which is commonly considered to be the top limit of daily intake for adults.
Recipes: A number of sites on the Internet have collections of recipes using Fish Sauce, including Thai Table, which has a long list of them. 
Fish Sauce appears in a dipping sauce called Nuoc Cham, which is commonly served as a table condiment in Vietnamese homes. This sauce also works as a dip for a variety of dumpling type foods from other Asian cuisines, such as gyoza or pot stickers.
Because the Fish Sauce is diluted with water in Nuoc Cham, this may be a good choice for persons concerned about sodium.
Here’s a simple recipe that makes about 10 tablespoons:
1 fresh hot red chili pepper
2 cloves garlic
4 teaspoons sugar
¼ fresh lime
¼ cup Fish Sauce, Nuoc Mam
5 tablespoons water
First, peel the garlic and set aside. Split the chili pepper lengthwise and remove the seeds and membranes.Cut it into pieces and put into a mortar with the garlic and sugar.
Pound these ingredients into a paste.
Then squeeze the lime juice into a paste and remove the lime fruit from the sections and add it to the paste. A small sharp knife works well for this. Crush and mash the mixture a bit more, then add the Fish Sauce and water and mix well. This is a good dipping sauce for meatballs, dumplings, plain fish or vegetable dishes.
For Further Information:
 Miriam Ferrari, Oriental Step-by-Step Cookbook (New York: Internatioinal Culinary Society 1990) — http://www.bookfinder.com/dir/i/Oriental_Step-By-Step_Cookbook/0517035693/
 “Fish Sauce,” Self Nutrition — http://www.bookfinder.com/dir/i/Oriental_Step-By-Step_Cookbook/0517035693/
 Tiparos Company Information — http://www.tiparos.co.th/corporate.htm
 Recipes – a good source is Thai Table — http://www.thaitable.com/thai/ingredient/fish-sauce
For a Vietnamese angle, see About.com — http://chinesefood.about.com/od/southeastasian/r/vietnamsauce.htm
For some Philippine ideas, see Yummy — http://www.yummy.ph/everyday-recipes/all-recipes/search/fish-sauce
Cambodian at Khmer Krom — http://www.khmerkromrecipes.com/recipes/recipe42.html
Laotian, for example at the Boat Landing site — http://www.foodfromnorthernlaos.com/tag/lao-recipes/
Burmese — How to Choose Fish Sauce — http://www.hsaba.com/blog/how-to/choose-fish-sauce
Also, Burmese Curry Sauce at Yummiy — http://www.yummly.com/recipes/burmese-curry-sauce