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"Peanuts...A Star of Asian Cuisine" (http://www.aboutpeanuts.com/star.html)

The 1995 "International Conference on the Diets of Asia", sponsored by Oldways Preservation and Exchange Trust, Cornell University and Harvard School of Public Health was held November 29 to December 2 in San Francisco. The focus of the four day seminar was to explore the health effects of following a diet common in the agricultural regions of Asia - diets high in vegetables, grains, fruits and other plant products and low in animal products. Epidemiological and clinical studies were presented that demonstrated that these diets can contribute to good cardiovascular health, decrease the risks of some kinds of cancer, and may account for the longer life expectancy rates found in Asia. Since one of the primary public health issues facing Americans is the overabundance of food, especially animal protein and fat, a goal of the conference was to promote the idea of substituting plant based foods for animal based foods.

An adjunct conference, "Nuts, Legumes and Health, Perspectives from Asia and The Pacific," was held on November 28 and November 29. Conference participants explored the role of nuts and legumes in the traditional diets of Asia. The central theme of the conference was that nuts and legumes, including peanuts, are integral to the exceedingly healthy traditional diets of Asia. Many of the food writers and chefs at the conference placed the peanut squarely in the center of the traditional Asian diet. Peanuts provide an important source of protein, plant fat, and other nutrients. During both conferences, leading scientists, chefs, culinary historians, and cookbook authors discussed their research and experiences regarding the influence of the traditional diets of Asia on health and longevity.

A Nobel Past

During the conference on nuts and legumes, the history of the peanut and it's importance in the cuisines of Asia was discussed by many culinary experts. Anya von Bremzen, author of "Terrific Pacific" and "Please to the Table", profiled the considerable history of the peanut from it's beginnings in the Andean lowlands to it's current stature as a star of flavor and texture in the cuisines of Asia, Europe, Africa and the Americas. The peanut is one of the most important food exports from the Americas to Asia and elsewhere says Ms. Bremzen. "Unlike other more chameleon-like ingredients which appear in cuisines across the world, the flavor of the peanut is so rich and unmistakable that any dish flavored with ground peanuts will have a similar flavor. Therefore, there will be a continuity in taste between an Indonesian peanut sauce, a West African soup, Chinese noodles, Peruvian stew, and a peanut butter sandwich," said Ms. Bremzen.
The peanut was clearly important as a food source to the Incas who fashioned solid gold peanut necklaces and ornaments. Ms. Bremzen suggests that peanuts might have had ceremonial importance on the basis of recent excavations in Peru, since some ceremonial sites were covered with peanut shells. "One can conjure up a rather gruesome picture of sacrifices taking place with spectators merrily munching on peanuts," said Ms. Bremzen.

The Spanish took the peanut back to Europe, then to Africa and Asia. It was immediately recognized for it's taste and nutritional value, and became a major source of protein in Asia and also in Africa. The Chinese used peanuts to create sauces, boiled them like beans, deep fried them in hot oil, and tossed them into stir-fried dishes. They also pounded peanuts with sugar to create a filling for sweet buns, as well as using them in other confectioneries.

Peanuts Around The World

Throughout Asia, the peanut has been an important food. In Malaysia, Singapore, Indonesia, Thailand, and other countries peanut sauces are served along with grilled meats to add flavor. Ms. Bremzen speculates that the reason the Southeast Asian dish Satay - generally a grilled meat on a skewer dipped in a peanut sauce - is so popular in the United States is that it tastes similar to the ever popular American peanut butter. In Thai cuisine, in particular, crushed peanuts are an essential garnish for salads, noodles and rice dishes.

One of the most important uses of peanuts in Asia, according to Ms. Bremzen, is as a source of oil. The Chinese were and are "master fryers" and the peanut has endured because of the mild and colorless quality of its oil. It can also be heated to high temperatures without burning.

Madhur Jaffrey, Indian cuisine cookbook author, actress, and host of Madhur Jaffrey's Far Eastern Cookery on the BBC, also spoke about the importance of the peanut in Asian cuisines. Ms. Jaffrey asserted that in many parts of Asia, the "nutty" flavor was as important as the "Five Flavors" of Chinese culinary philosophy: salty, sweet, sour, bitter and hot. She described how the Indonesians use peanuts, which she termed a "very important food" for them. They boil peanuts in salted water and pour chili sauce over the dish. They also add chopped peanuts to many salads. This is true all over South East Asia, including Thailand and Vietnam, according to Ms. Jaffrey. She described the common practice of toasting peanuts in a fresh wok and rubbing off the skin before chopping and adding to salads or other dishes. She mentioned a popular Vietnamese salad made with kolrabi and peanuts and the Thai salad of julienned green papaya pounded with roasted peanuts.

Ms. Jaffrey described peanuts as a popular snack food and ingredient in many of the delicious foods of her native India. She told of the popular street snack of peanuts mixed with dried legumes, which is eaten out of the hand, and resembles granola. In India, peanuts are also cooked in soups and stews, deep fried and used to thicken curries and sauces. Ms. Jaffrey shared a more personal food story with the conference participants, when she discussed the steamed young eggplants with peanut sauce that she served at her daughter's wedding.

Ms. Jaffrey and other culinary experts addressed the crucial element of yin and yang in the Asian diet. A balanced diet in Asia means more than just eating the proper amount of fruits, vegetables, grains, sugars, fats and meats. It also means balance of the body's energies - yin and yang. In Chinese culinary philosophy, just as there are five flavors - salty, sweet, sour, bitter and hot - there are also five "temperatures." The five temperatures are hot (yang), warm (yang), neutral, cool (yin) and cold (yin). Balance of the body's energies is attained by eating the proper amounts of each temperature. Peanuts are classified as neutral, along with other important foods in the Asian diet, such as rice, mushrooms and cabbage.

Other food writers and chefs also discussed the widespread use of nuts throughout Asia, or in their homes and restaurants. Mai Pham, chef and owner of Lemon Grass restaurant in Sacramento, California and author of The Best of Vietnamese and Thai Cooking, discussed the role that nuts and legumes played in childhood foods in her native Thailand. She told of her family's diet which was heavy with noodles, rice, and vegetables and very light with meat. "We ate meat only on Sundays," she said. Nuts and legumes were used in soups, salads and other dishes, like boiled peanuts, which were a breakfast treat. "Peanuts were used as garnish for everything," she said.

Naomi Duguid, a Canadian food writer who has traveled extensively throughout Asia, described many of the traditional cuisines that include nuts and legumes, as "simple sustaining foods - things that people eat everyday."

Neela Paniz, chef and owner of Bombay Cafe in Santa Monica, California, described the Indian new year in which nuts are integral to the celebrations. Nuts "show good health and wealth," she said, and they must be offered to guests who drop by the house.

Scientific Studies

The medical and health traditions of East and West merged during the conference as western medical researchers seemed to proclaim peanuts, and other nuts, to be helpful in promoting good health. Western diets have de-emphasized the eating of nuts, with the exception of peanut butter, much to our detriment, said Dr. Joan SabatŽ, Associate Professor, Department of Nutrition at the School of Public Health of Loma Linda University. Dr. SabatŽ stressed the need for western diets to include more legumes and nuts in order to protect against the two leading chronic diseases of this century - cardiovascular disease and cancer.

Dr. SabatŽ acknowledged that scientists don't know exactly why nuts and legumes are protective, but he speculates it could be many factors including arginine-rich protein, fiber, trace minerals, monounsaturated fats, antioxidants, phytochemicals, or possibly other as yet unidentified elements present in nuts. Dr. SabatŽ explained that nuts and legumes share several important characteristics that make them valuable for traditional societies: they can be stored without refrigeration, and they are high in protein and other vital nutrients. Dr. SabatŽ linked high rates of heart disease and other chronic diseases in the United States with low intakes of nuts and legumes. He noted that the most common form of nuts and legumes in the diet of Americans is likely to be peanuts in the form of peanut butter. "Unless you take into account the peanut, recent western patterns of eating de-emphasize the eating of nuts," he lamented.

Dr. SabatŽ discussed the Seventh Day Adventist Study, an epidemiological survey of 26,000 Seventh Day Adventists in California and the Iowa Women's Study of 34,000 women. Both epidemiological studies demonstrated a marked inverse relationship between nut consumption and death by heart disease. In the Adventist study, those participants who ate nuts, (a high portion of which were peanuts at least 5 times per week), were only half as likely to die from heart disease during the same time period as those who never ate nuts. Even those who ate nuts only once a week received some benefits, experiencing 25% fewer incidence of heart disease than those who avoided nuts altogether. The range of participants in the study went from vegetarians to average U.S. meat eaters. In the Iowa study, fewer women ate nuts. The women who ate nuts, however, were only 40% as likely to die from heart disease as those who never ate nuts.

Other scientists discussed studies in which various types of nuts have been shown to lower cholesterol levels when added to the diet of healthy or hypercholesterolemic individuals. The results were uniformly positive. Including nuts in the diet appeared to decrease the overall cholesterol levels, particulary LDL or bad cholesterol, which has been associated with increased risk of heart disease.

"Nuts are the extremely complex sum of their bioactive compounds," explained Dr. Gene Spiller, Director of the Health Research and Studies Center in Los Altos. Because nuts contain so many different nutrients and phytochemicals, it may be impossible to know exactly why they are so beneficial. Dr. Spiller pointed to their high content of "good fats," fiber, vitamin E, copper, magnesium, zinc, and arginine-rich protein as contributing to their ability to lower blood lipids (overall cholesterol levels) and reduce the oxidation of LDL cholesterol.

One study which looked specifically at the cholesterol-reducing effects of peanuts was conducted and presented by Dr. Dawn Johnson O'Byrne, a Research Scientist, Sports and Cardiovascular Nutritionist from Gainesville, Florida. Dr. O'Byrne studied the cardiovascular benefits of adding the peanuts to the diet. "Very typical Americans can fit peanuts into their diets with ease," said Dr. O'Byrne. Her study incorporated SunOleic 95R peanuts to the diets of 36 hypercholesterolemic, post-menopausal women. The SunOleic 95R is a new peanut variety, now being researched, with a unique fatty acid profile. Eighty-five percent of the oils are monounsaturated in the SunOleic peanut, compared with 54% monounsaturated in other peanut varieties. The SunOleic peanut was chosen because its fat profile closely resembled the fat profile of olive oil, an essential ingredient in the heart-healthy Mediterranean diet. Also, the peanuts were considerably less expensive than olive oil.

Dr. O'Byrne's study demonstrated that low-fat diets with a high proportion of monounsaturated fats, in this case from peanuts, can help to reduce cholesterol of patients. All of her participants were already following low-fat diets before beginning the study. By substituting peanuts for other sources of protein and fat, however, their cholesterol levels were lowered further. Contrary to the concerns of many of the women, they did not gain weight by adding peanuts to their diets. More research will be done on this area.

Peanuts are also high in arginine protein, which has been seen to improve wound healing and immunity. Dr. O'Byrne stressed that the nutrients found in nuts, including potassium, phosphorous, magnesium, zinc, manganese, copper and vitamin E are vital for proper function and health of muscles and bones and protect against free-radical damage. American women are "woefully lacking" in zinc and copper, she said, because these nutrients are also found in fatty meats, liver and eggs. As those foods have been eliminated from the diets of many women, the zinc and copper must be provided from new sources. Dr. O'Byrne pointed out that 50 grams of nuts contain as much fiber as 1/2 cup of wheat bran -- foods high in fiber are thought to reduce cholesterol.

Dr. O'Byrne's study demonstrates that Americans, especially women who do not allow themselves to eat nuts because of the fat content, can improve their diets by added nuts.

The obsession with avoiding fat may even be harmful for some people, explained Ann Coulston, M.S., R.D., a Senior Research Dietitian at Stanford University Medical Center. Those with Diabetes Mellitus, or Type II Diabetes have been advised not to follow the American Heart Association Step I high carbohydrate diet, which is only 30% fat. Although these patients have a two to three times increased risk of heart disease, lowering their fat content has been found to exacerbate the factors that can contribute to heart disease, such as raised triglyceride levels, and lowered HDL or "good" cholesterol levels. Many diabetes patients are now being advised to consume a diet higher in overall fat, but low in saturated fat. "It doesn't make sense to give a blanket recommendation that a high carbohydrate, low fat diet is the best," said Ms. Coulston.

The importance of whole, unprocessed and unrefined plant foods, such as peanuts, in the diet was discussed by many of the conference participants. "We cannot disaggregate nutrients from the foods in which they come," stressed Dr. Tim Byers, Professor of Preventative Medicine, University of Colorado School of Medicine.

He cautioned Americans against searching for instant cures by taking vitamin supplements. He discussed studies which tend to demonstrate that many of the preventative effects of vitamins and minerals when consumed from plant foods, such as vitamin E and vitamin C, are not duplicated when those vitamins are consumed in the form of supplements. Two major studies, in fact, showed that taking vitamin supplements either had no positive effect or increased the risk of certain cancers. "Whole foods are a complex mixture of very complex matrixes that deliver nutrients, and we cannot distill out of fruits and vegetables the nutrients that prevent cancer," he said.

Many of the research scientists who presented their studies about the traditional diets of Asia, highlighted the use of whole foods and the heavy reliance on plant products in those diets. Dr. T. Colin Campbell, Professor of Nutritional Biochemistry at Cornell, directed an extensive China study which surved 11,000 Chinese households about the Chinese dietary pattern. He described the Chinese principal of fan-tsai. Fan foods are basic foods that appear in the lower levels of the pyramid. They include rice, wheat, noodles, corn, sorghum and sweet potatoes. Fan varies by region, depending on the primary staple of that region. Tsai foods include meat and some vegetables. The formula for healthy living is generally considered more fan and less tsai. "Children who eat more fan and less tsai are praised," explained Dr. Campbell.

Dr. Campbell also said that, "There is a remarkable continuity of China's food systems throughout history and across regions." People in most regions of China are eating much as people have for centuries. According to the China study, the average Chinese consumes 2,630 calories per day, of which 71% is carbohydrate, 14% is fat, 5% is alcohol, and 10% is protein, but only 11% of the overall protein comes from animal sources. Dr. Campbell and other scientists expressed concern that the traditional Asian diets are being modified to include more animal protein and saturated fat as economic development increases in those regions.


The Asian Pyramid

One goal of the conference was to examine the traditional Asian diet and to present some recommendations about healthy diets. To that end, a preliminary diet pyramid was designed and presented to conference participants. The preliminary concept of the Traditional Healthy Asian Diet Pyramid stressed the importance of including more whole plant products in the diet to prevent chronic diseases and promote longer life expectancy. The pyramid was based loosely on the traditional diets, such as those described by Dr. Campbell, that are eaten throughout Asia.

The lowest, and largest, levels of the pyramid include rice, grains, corn, tubers, and roots. These should be consumed every day in sufficient amounts. The next level up includes, fruits, vegetables, legumes, nuts and seeds, and peanuts. These also should be consumed daily. Legumes, nuts and seeds are placed in the center of the Pyramid, along with other fruits and vegetables, to demonstrate importance and their positive health benefits. Vegetable oil can be consumed in smaller quantities daily. Fish and dairy are optional daily. Sweets, eggs and poultry may be consumed weekly, but meats are recommended to be consumed monthly or in small quantities if consumed more often.