Post by Rene on Feb 14, 2009 10:15:01 GMT -7
yol1230 (Original Message) Sent: 24/04/2008
Just wondering if sweet potatoe is OK.
From: Blue_Opal2003 Sent: 24/04/2008
In short, it appears the answer is "Yes"
I did a bit of 'digging around' to be sure of this & shall add a rather indepth, nice article "Nightshades" and I think another just for sweet potatoes
From: Blue_Opal2003 Sent: 24/04/2008
If you were to design the world’s most perfect food, what would you put in it? In addition to great taste, you’d be sure it contained a powerhouse of nutrients. Of course, you’d also make it a good source of dietary fiber. And, since the sky’s the limit here, why not make it fat-and cholesterol-free, low sodium, and easy to prepare. Sound like too much to ask from a single food? Mother Nature didn’t think so. She’s already provided us with this perfection in the form of a very unassuming vegetable: the sweetpotato.
That’s right, SweetPotatoes hide a veritable treasure trove of vitamins and minerals. They are a first-rate provider of vitamin A and beta carotene (a compound your body converts into vitamin A), both of which promote healthy skin, hair and eyesight. In fact, a serving of SweetPotatoes have four times the recommended daily allowance for beta carotene. Believe it or not, one cup of cooked sweetpotato provides so much beta carotene that it would take 23 cups of broccoli to provide the same amount!
Sweetpotatoes also contain significant amounts of vitamins C and are a fair source of vitamin E. Along with beta carotene, these vitamins make up the terrific trio of antioxidant nutrients scientists believe may help prevent heart disease and cancer, bolster the immune system, and even slow the aging process. One medium sweetpotato provides nearly half of your daily requirement of vitamin C. And, the fact that SweetPotatoes are fat-free makes them a real vitamin E standout. Vitamin E is a fat-soluble vitamin, meaning that it is usually found in foods rich in fat such as vegetable oils, nuts and avocados. But one sweetpotato provides a healthy dose of vitamin E with no fat at all. As if all this weren’t good enough, SweetPotatoes are also a great source of dietary fiber. When eaten with the skin, they offer more fiber than oatmeal! With all this for only about 120 calories per medium sweetpotato, you’ve got to admit it would be hard to find a food with a better all-around package.
Word of this extraordinary nutritional value is getting out. Recently, SweetPotatoes took top honors in two surveys focusing of the nutritional benefits of vegetables. In the first, The Nutrition Action Health Letter rated 58 vegetables from artichokes to winter squash, adding up the percentages of recommended daily allowances for six nutrients (vitamin A, vitamin C, folate, iron, copper and calcium,), plus fiber. Sweetpotatoes scored a whopping 582; its nearest competitor, a raw carrot, came in at 434. The baked potato rated a paltry 114.
In the second survey the consumer watchdog group, Center for Science in the Public Interest (CSPI), rated the relative nutritional value of common vegetables based on their content of fiber, complex carbohydrates, protein, vitamins A and C, iron and calcium. Once again, the sweetpotato came out on top with a score of 184 compared to a similarly prepared potato, which came in at 83. Carrots, the self-proclaimed beta carotene king, scored only 30.
With all these facts it’s easy to see why SweetPotatoes, once reserved just for the holidays, should be considered year-round as an important addition to a healthy diet. If you’re familiar with them only as a fat-loaded, overly-sweet Thanksgiving side dish, you’ll be amazed at how much more SweetPotatoes can be! A great staple to keep on hand in the kitchen, they can be baked, .... steamed, boiled, sautéed or grilled. Enjoy them on their own or in everything from entrees, salads and side dishes to muffins, breads and desserts.
Instead of a plain potato, bake .... SweetPotatoes to accompany any type of meat, poultry or fish. Add chunks of SweetPotatoes to soups, stews and even chili. Raw SweetPotatoes can be peeled and grated to add to salads or thinly sliced to star on a vegetable and dip platter. Or, for a delicious change-of-pace breakfast, try a baked .... sweetpotato topped with low-fat yogurt and a drizzling of honey.
The evidence is in, so don’t delay! Start making SweetPotatoes a regular and important part of your diet now. However you enjoy them, your taste buds and your body will thank you!
From: [http://www.ontariosweetpotato.com/index.php?option=com_frontpage&Itemid=1]
[http://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=128]
From: Blue_Opal2003 Sent: 24/04/2008
Although sweet potatoes may be part of the Thanksgiving tradition, be sure to add these wonderful naturally sweet vegetables to your meals throughout the year; they are some of the most nutritious vegetables around. Sweet potatoes can be found in your local markets year-round, however they are in season in November and December.
The sweet potato has yellow or orange flesh, and its thin skin may either be white, yellow, orange, red or purple. Sometimes this root vegetable will be shaped like a potato, being short and blocky with rounded ends, while other times it will be longer with tapered ends. There is often much confusion between sweet potatoes and yams; the moist-fleshed, orange-colored root vegetable that is often called a "yam" is actually a sweet potato.
Health Benefits
How sweet it is for your health to eat sweet potatoes! Not only do they taste like dessert, here's the latest research on sweet potatoes surprising benefits.
Unique Proteins with Potent Antioxidant Effects
Sweet potato contain unique root storage proteins that have been observed to have significant antioxidant capacities. In one study, these proteins had about one-third the antioxidant activity of glutathione-one of the body's most impressive internally produced antioxidants. Although future studies are needed in this area, count on these root proteins to help explain sweet potatoes' healing properties.
A Sweet Source of Good Nutrition
Our food ranking system also showed sweet potato to be a strong performer in terms of traditional nutrients. This root vegetable qualified as an excellent source of vitamin A (in the form of beta-carotene), a very good source of vitamin C and manganese, and a good source of copper, dietary fiber, vitamin B6, potassium and iron. How do these sweet potato nutrients support our health?
As an excellent source of vitamin A (in the form of beta-carotene) and a very good source of vitamin C, sweet potatoes have healing properties as an antioxidant food. Both beta-carotene and vitamin C are very powerful antioxidants that work in the body to eliminate free radicals. Free radicals are chemicals that damage cells and cell membranes and are associated with the development of conditions like atherosclerosis, diabetic heart disease, and colon cancer. This may explain why beta-carotene and vitamin C have both been shown to be helpful for preventing these conditions.
Since these nutrients are also anti-inflammatory, they can be helpful in reducing the severity of conditions where inflammation plays a role, such as asthma, osteoarthritis, and rheumatoid arthritis.
In addition, sweet potatoes are a good source of vitamin B6, which is needed to convert homocysteine, an interim product created during an important chemical process in cells called methylation, into other benign molecules. Since high homocysteine levels are associated with an increased risk of heart attack and stroke, having a little extra vitamin B6 on hand is a good idea.
If you or someone you love is a smoker, or if you are frequently exposed to secondhand smoke, then making vitamin A-rich foods, such as sweet potatoes, part of your healthy way of eating, may save your life, suggests research conducted at Kansas State University.
While studying the relationship between vitamin A, lung inflammation, and emphysema, Richard Baybutt, associate professor of nutrition at Kansas State, made a surprising discovery: a common carcinogen in cigarette smoke, benzo(a)pyrene, induces vitamin A deficiency.
Baybutt's earlier research had shown that laboratory animals fed a vitamin A-deficient diet developed emphysema. His latest animal studies indicate that not only does the benzo(a)pyrene in cigarette smoke cause vitamin A deficiency, but that a diet rich in vitamin A can help counter this effect, thus greatly reducing emphysema.
Baybutt believes vitamin A's protective effects may help explain why some smokers do not develop emphysema. "There are a lot of people who live to be 90 years old and are smokers," he said. "Why? Probably because of their diet…The implications are that those who start smoking at an early age are more likely to become vitamin A deficient and develop complications associated with cancer and emphysema. And if they have a poor diet, forget it." If you or someone you love smokes, or if your work necessitates exposure to second hand smoke, protect yourself by making sure at least one of the World's Healthiest Foods that are rich in vitamin A, such as sweet potatoes, is a daily part of your healthy way of eating.
So, the next time you have the urge for something sweet, how about a thick slice of sweet potato pie? It's one dessert guaranteed to satisfy your whole body, not just your sweet tooth.
Description
Depending upon the sweet potato variety, of which there are about 400, its flesh may be either white, yellow or orange, and its thin skin may either be white, yellow, orange, red or purple. Sometimes this root vegetable will be shaped like a potato, being short and blocky with rounded ends, while other times it will be longer with tapered ends.
Sweet potatoes are grouped into two different categories depending upon the texture they have when cooked: some are firm, dry, and mealy, while others are soft and moist. In both types, the taste is starchy and sweet with different varieties having different unique tastes.
The moist-fleshed, orange-colored root vegetable that is often thought of as a "yam" is actually a sweet potato. It was given this name after this variety of sweet potato was introduced into the United States in the mid-20th century in order to distinguish it from the white-fleshed sweet potato to which most people were accustomed. The name "yam" was adopted from "nyami", the African word for the root of the Dioscoreae genus of plants that are considered true yams [http://www.whfoods.com/genpage.php?tname=foodspice&dbid=113].
While there are attempts to distinguish between the two, such as the mandatory labeling by the U.S. Department of Agriculture that the moist-fleshed, orange-colored sweet potatoes that are labeled as "yams" also be accompanied by the label "sweet potato," when most people hear the term "yam" they usually think of the orange-colored sweet potato as opposed to the true yam, the traditional Dioscoreae family root vegetable.
Sweet potatoes belong to the Convolvulaceae plant family and are known by the scientific name of Ipomoea batatas.
History
Sweet potatoes are native to Central America and are one of the oldest vegetables known to man. They have been consumed since prehistoric times as evidenced by sweet potato relics dating back 10,000 years that have been discovered in Peruvian caves.
Christopher Columbus brought sweet potatoes to Europe after his first voyage to the New World in 1492. By the 16th century, they were brought to the Philippines by Spanish explorers and to Africa, India, Indonesia and southern Asia by the Portuguese. Around this same time, sweet potatoes began to be cultivated in the southern United States, where they still remain a staple food in the traditional cuisine. In the mid-20th century, the orange-fleshed sweet potato was introduced to the United States and given the name "yam" to distinguish it from other sweet potatoes. Sweet potatoes are a featured food in many Asian and Latin American cultures. Today, the main commercial producers of sweet potatoes include China, Indonesia, Vietnam, Japan, India and Uganda.
How to Select and Store
Choose sweet potatoes that are firm and do not have any cracks, bruises or soft spots. Avoid those that are displayed in the refrigerated section of the produce department since cold temperature negatively alters their taste.
Sweet potatoes should be stored in a cool, dark and well-ventilated place, where they will keep fresh for up to ten days. Ideally, they should be kept out of the refrigerator in a cool, dry, dark place not above 60?F, which would fit the characteristics of a root cellar. Yet since most people don't have root cellars, we'd suggest just keeping your sweet potatoes loose (not in a plastic bag) and storing them in a cool, dark, and well-ventilated cupboard away from sources of excess heat (like the stove).
How to Enjoy
For some of our favorite recipes, click Recipes. [http://www.whfoods.com/recipestoc.php]
Tips for Preparing Sweet Potatoes:
If you purchase organically grown sweet potatoes, you can eat the entire tuber, flesh and skin. Yet, if you buy conventionally grown ones, you should peel them before eating since sometimes the skin is treated with dye or wax; if preparing the sweet potato whole, just peel it after cooking.
As the flesh of sweet potatoes will darken upon contact with the air, you should cook them immediately after peeling and/or cutting them. If this is not possible, to prevent oxidation, keep them in a bowl covered completely with water until you are ready to cook them.
A Few Quick Serving Ideas:
Purée cooked sweet potatoes with bananas, maple syrup and cinnamon. Top with chopped walnuts.
Steam cubed sweet potatoes, tofu, and broccoli. Mix in raisins and serve hot or cold with a curried vinaigrette dressing.
Desserts made with sweet potatoes are an autumn favorite but can be enjoyed year round. Try making sweet potato pie, bread, muffins or pudding.
Baked sweet potatoes are delicious even when served cold and therefore make a great food to pack in to-go lunches.
Safety
Sweet potatoes are among a small number of foods that contain measurable amounts of oxalates, naturally-occurring substances found in plants, animals, and human beings. When oxalates become too concentrated in body fluids, they can crystallize and cause health problems. For this reason, individuals with already existing and untreated kidney or gallbladder problems may want to avoid eating sweet potatoes. Laboratory studies have shown that oxalates may also interfere with absorption of calcium from the body. Yet, in every peer-reviewed research study we've seen, the ability of oxalates to lower calcium absorption is relatively small and definitely does not outweigh the ability of oxalate-containing foods to contribute calcium to the meal plan. If your digestive tract is healthy, and you do a good job of chewing and relaxing while you enjoy your meals, you will get significant benefits - including absorption of calcium - from calcium-rich foods plant foods that also contain oxalic acid. Ordinarily, a healthcare practitioner would not discourage a person focused on ensuring that they are meeting their calcium requirements from eating these nutrient-rich foods because of their oxalate content. For more on this subject, please see "Can you tell me what oxalates are and in which foods they can be found?" [http://www.whfoods.com/genpage.php?tname=george&dbid=48]
Nutritional Profile Introduction to Food Rating System Chart
The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents (similar to other information presented in the website, this DV is calculated for 25-50 year old healthy woman); the nutrient density rating; and, the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised. Read detailed information on our Food and Recipe Rating System.
Sweet potato, baked, with skin
1.00 each
77.00 grams
95.39 calories
Nutrient
Amount
DV
(%)
Nutrient
Density
World's Healthiest
Foods Rating
vitamin A
13107.70 IU
262.2
49.5
excellent
vitamin C
17.06 mg
28.4
5.4
very good
manganese
0.52 mg
26.0
4.9
very good
copper
0.26 mg
13.0
2.5
good
dietary fiber
3.14 g
12.6
2.4
good
vitamin B6 (pyridoxine)
0.25 mg
12.5
2.4
good
potassium
306.05 mg
8.7
1.7
good
iron
1.46 mg
8.1
1.5
good
World's Healthiest
Foods Rating
Rule
excellent
DV>=75%
OR
Density>=7.6
AND
DV>=10%
very good
DV>=50%
OR
Density>=3.4
AND
DV>=5%
good
DV>=25%
OR
Density>=1.5
AND
DV>=2.5%[/size]
References
Baybutt RC, Hu L, Molteni A. Vitamin A deficiency injures lung and liver parenchyma and impairs function of rat type II pneumocytes. J Nutr. 2000 May;130(5):1159-65. PMID:10801913.
Ensminger AH, Ensminger, ME, Kondale JE, Robson JRK. Foods & Nutriton Encyclopedia. Pegus Press, Clovis, California 1983.
Ensminger AH, Esminger M. K. J. e. al. Food for Health: A Nutrition Encyclopedia. Clovis, California: Pegus Press; 1986. PMID:15210.
Fortin, Francois, Editorial Director. The Visual Foods Encyclopedia. Macmillan, New York 1996.
Hou WC, Chen YC, Chen HJ, et al. Antioxidant activities of trypsin inhibitor, a 33 KDa root storage protein of sweet potato (Ipomoea batatas (L.) Lam cv. Tainong 57). J Agric Food Chem 2001 Jun;49(6):2978-81. PMID:13860.
Li T, Molteni A, Latkovich P, Castellani W, Baybutt RC. Vitamin A depletion induced by cigarette smoke is associated with the development of emphysema in rats. J Nutr. 2003 Aug;133(8):2629-34. PMID:12888649.
Suzuki K, Ito Y, Nakamura S et al. Relationship between serum carotenoids and hyperglycemia: a population- based cross-sectional study. J Epidemiol 2002 Sep;12(5):357-66 2002.
Terahara N, Konczak-Islam I, Nakatani M, et al. Anthocyanins in callus induced from purple storage root of Ipomoea batatas L. Phytochemistry 2000 Aug;54(8):919-22. PMID:13870.
Wallerstein C. New sweet potato could help combat blindness in Africa. BMJ 2000 Sep 30;321(7264):786. PMID:13850.
Wood, Rebecca. The Whole Foods Encyclopedia. New York, NY: Prentice-Hall Press; 1988. PMID:15220.
Ylonen K, Alfthan G, Groop, L et al. Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study. Am J Clin Nutr. 2003 Jun; 77(6):1434-41 2003.
Recipes [http://www.whfoods.com/recipestoc.php]
Oxalates [http://www.whfoods.com/genpage.php?tname=george&dbid=48]
Vitamin A [http://www.whfoods.com/genpage.php?tname=nutrient&dbid=106]
Vitamin B6 [http://www.whfoods.com/genpage.php?tname=nutrient&dbid=108]
vitamin C [http://www.whfoods.com/genpage.php?tname=nutrient&dbid=109]
[/color]
Just wondering if sweet potatoe is OK.
From: Blue_Opal2003 Sent: 24/04/2008
In short, it appears the answer is "Yes"
I did a bit of 'digging around' to be sure of this & shall add a rather indepth, nice article "Nightshades" and I think another just for sweet potatoes
From: Blue_Opal2003 Sent: 24/04/2008
Sweet Potatoes: Mother Nature's Best Work
If you were to design the world’s most perfect food, what would you put in it? In addition to great taste, you’d be sure it contained a powerhouse of nutrients. Of course, you’d also make it a good source of dietary fiber. And, since the sky’s the limit here, why not make it fat-and cholesterol-free, low sodium, and easy to prepare. Sound like too much to ask from a single food? Mother Nature didn’t think so. She’s already provided us with this perfection in the form of a very unassuming vegetable: the sweetpotato.
That’s right, SweetPotatoes hide a veritable treasure trove of vitamins and minerals. They are a first-rate provider of vitamin A and beta carotene (a compound your body converts into vitamin A), both of which promote healthy skin, hair and eyesight. In fact, a serving of SweetPotatoes have four times the recommended daily allowance for beta carotene. Believe it or not, one cup of cooked sweetpotato provides so much beta carotene that it would take 23 cups of broccoli to provide the same amount!
Sweetpotatoes also contain significant amounts of vitamins C and are a fair source of vitamin E. Along with beta carotene, these vitamins make up the terrific trio of antioxidant nutrients scientists believe may help prevent heart disease and cancer, bolster the immune system, and even slow the aging process. One medium sweetpotato provides nearly half of your daily requirement of vitamin C. And, the fact that SweetPotatoes are fat-free makes them a real vitamin E standout. Vitamin E is a fat-soluble vitamin, meaning that it is usually found in foods rich in fat such as vegetable oils, nuts and avocados. But one sweetpotato provides a healthy dose of vitamin E with no fat at all. As if all this weren’t good enough, SweetPotatoes are also a great source of dietary fiber. When eaten with the skin, they offer more fiber than oatmeal! With all this for only about 120 calories per medium sweetpotato, you’ve got to admit it would be hard to find a food with a better all-around package.
Word of this extraordinary nutritional value is getting out. Recently, SweetPotatoes took top honors in two surveys focusing of the nutritional benefits of vegetables. In the first, The Nutrition Action Health Letter rated 58 vegetables from artichokes to winter squash, adding up the percentages of recommended daily allowances for six nutrients (vitamin A, vitamin C, folate, iron, copper and calcium,), plus fiber. Sweetpotatoes scored a whopping 582; its nearest competitor, a raw carrot, came in at 434. The baked potato rated a paltry 114.
In the second survey the consumer watchdog group, Center for Science in the Public Interest (CSPI), rated the relative nutritional value of common vegetables based on their content of fiber, complex carbohydrates, protein, vitamins A and C, iron and calcium. Once again, the sweetpotato came out on top with a score of 184 compared to a similarly prepared potato, which came in at 83. Carrots, the self-proclaimed beta carotene king, scored only 30.
With all these facts it’s easy to see why SweetPotatoes, once reserved just for the holidays, should be considered year-round as an important addition to a healthy diet. If you’re familiar with them only as a fat-loaded, overly-sweet Thanksgiving side dish, you’ll be amazed at how much more SweetPotatoes can be! A great staple to keep on hand in the kitchen, they can be baked, .... steamed, boiled, sautéed or grilled. Enjoy them on their own or in everything from entrees, salads and side dishes to muffins, breads and desserts.
Instead of a plain potato, bake .... SweetPotatoes to accompany any type of meat, poultry or fish. Add chunks of SweetPotatoes to soups, stews and even chili. Raw SweetPotatoes can be peeled and grated to add to salads or thinly sliced to star on a vegetable and dip platter. Or, for a delicious change-of-pace breakfast, try a baked .... sweetpotato topped with low-fat yogurt and a drizzling of honey.
The evidence is in, so don’t delay! Start making SweetPotatoes a regular and important part of your diet now. However you enjoy them, your taste buds and your body will thank you!
From: [http://www.ontariosweetpotato.com/index.php?option=com_frontpage&Itemid=1]
[http://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=128]
From: Blue_Opal2003 Sent: 24/04/2008
Sweet potatoes
Although sweet potatoes may be part of the Thanksgiving tradition, be sure to add these wonderful naturally sweet vegetables to your meals throughout the year; they are some of the most nutritious vegetables around. Sweet potatoes can be found in your local markets year-round, however they are in season in November and December.
The sweet potato has yellow or orange flesh, and its thin skin may either be white, yellow, orange, red or purple. Sometimes this root vegetable will be shaped like a potato, being short and blocky with rounded ends, while other times it will be longer with tapered ends. There is often much confusion between sweet potatoes and yams; the moist-fleshed, orange-colored root vegetable that is often called a "yam" is actually a sweet potato.
Health Benefits
How sweet it is for your health to eat sweet potatoes! Not only do they taste like dessert, here's the latest research on sweet potatoes surprising benefits.
Unique Proteins with Potent Antioxidant Effects
Sweet potato contain unique root storage proteins that have been observed to have significant antioxidant capacities. In one study, these proteins had about one-third the antioxidant activity of glutathione-one of the body's most impressive internally produced antioxidants. Although future studies are needed in this area, count on these root proteins to help explain sweet potatoes' healing properties.
A Sweet Source of Good Nutrition
Our food ranking system also showed sweet potato to be a strong performer in terms of traditional nutrients. This root vegetable qualified as an excellent source of vitamin A (in the form of beta-carotene), a very good source of vitamin C and manganese, and a good source of copper, dietary fiber, vitamin B6, potassium and iron. How do these sweet potato nutrients support our health?
An Antioxidant-Rich, Anti-Inflammatory Food
As an excellent source of vitamin A (in the form of beta-carotene) and a very good source of vitamin C, sweet potatoes have healing properties as an antioxidant food. Both beta-carotene and vitamin C are very powerful antioxidants that work in the body to eliminate free radicals. Free radicals are chemicals that damage cells and cell membranes and are associated with the development of conditions like atherosclerosis, diabetic heart disease, and colon cancer. This may explain why beta-carotene and vitamin C have both been shown to be helpful for preventing these conditions.
Since these nutrients are also anti-inflammatory, they can be helpful in reducing the severity of conditions where inflammation plays a role, such as asthma, osteoarthritis, and rheumatoid arthritis.
In addition, sweet potatoes are a good source of vitamin B6, which is needed to convert homocysteine, an interim product created during an important chemical process in cells called methylation, into other benign molecules. Since high homocysteine levels are associated with an increased risk of heart attack and stroke, having a little extra vitamin B6 on hand is a good idea.
If you or someone you love is a smoker, or if you are frequently exposed to secondhand smoke, then making vitamin A-rich foods, such as sweet potatoes, part of your healthy way of eating, may save your life, suggests research conducted at Kansas State University.
While studying the relationship between vitamin A, lung inflammation, and emphysema, Richard Baybutt, associate professor of nutrition at Kansas State, made a surprising discovery: a common carcinogen in cigarette smoke, benzo(a)pyrene, induces vitamin A deficiency.
Baybutt's earlier research had shown that laboratory animals fed a vitamin A-deficient diet developed emphysema. His latest animal studies indicate that not only does the benzo(a)pyrene in cigarette smoke cause vitamin A deficiency, but that a diet rich in vitamin A can help counter this effect, thus greatly reducing emphysema.
Baybutt believes vitamin A's protective effects may help explain why some smokers do not develop emphysema. "There are a lot of people who live to be 90 years old and are smokers," he said. "Why? Probably because of their diet…The implications are that those who start smoking at an early age are more likely to become vitamin A deficient and develop complications associated with cancer and emphysema. And if they have a poor diet, forget it." If you or someone you love smokes, or if your work necessitates exposure to second hand smoke, protect yourself by making sure at least one of the World's Healthiest Foods that are rich in vitamin A, such as sweet potatoes, is a daily part of your healthy way of eating.
So, the next time you have the urge for something sweet, how about a thick slice of sweet potato pie? It's one dessert guaranteed to satisfy your whole body, not just your sweet tooth.
Description
Depending upon the sweet potato variety, of which there are about 400, its flesh may be either white, yellow or orange, and its thin skin may either be white, yellow, orange, red or purple. Sometimes this root vegetable will be shaped like a potato, being short and blocky with rounded ends, while other times it will be longer with tapered ends.
Sweet potatoes are grouped into two different categories depending upon the texture they have when cooked: some are firm, dry, and mealy, while others are soft and moist. In both types, the taste is starchy and sweet with different varieties having different unique tastes.
The moist-fleshed, orange-colored root vegetable that is often thought of as a "yam" is actually a sweet potato. It was given this name after this variety of sweet potato was introduced into the United States in the mid-20th century in order to distinguish it from the white-fleshed sweet potato to which most people were accustomed. The name "yam" was adopted from "nyami", the African word for the root of the Dioscoreae genus of plants that are considered true yams [http://www.whfoods.com/genpage.php?tname=foodspice&dbid=113].
While there are attempts to distinguish between the two, such as the mandatory labeling by the U.S. Department of Agriculture that the moist-fleshed, orange-colored sweet potatoes that are labeled as "yams" also be accompanied by the label "sweet potato," when most people hear the term "yam" they usually think of the orange-colored sweet potato as opposed to the true yam, the traditional Dioscoreae family root vegetable.
Sweet potatoes belong to the Convolvulaceae plant family and are known by the scientific name of Ipomoea batatas.
History
Sweet potatoes are native to Central America and are one of the oldest vegetables known to man. They have been consumed since prehistoric times as evidenced by sweet potato relics dating back 10,000 years that have been discovered in Peruvian caves.
Christopher Columbus brought sweet potatoes to Europe after his first voyage to the New World in 1492. By the 16th century, they were brought to the Philippines by Spanish explorers and to Africa, India, Indonesia and southern Asia by the Portuguese. Around this same time, sweet potatoes began to be cultivated in the southern United States, where they still remain a staple food in the traditional cuisine. In the mid-20th century, the orange-fleshed sweet potato was introduced to the United States and given the name "yam" to distinguish it from other sweet potatoes. Sweet potatoes are a featured food in many Asian and Latin American cultures. Today, the main commercial producers of sweet potatoes include China, Indonesia, Vietnam, Japan, India and Uganda.
How to Select and Store
Choose sweet potatoes that are firm and do not have any cracks, bruises or soft spots. Avoid those that are displayed in the refrigerated section of the produce department since cold temperature negatively alters their taste.
Sweet potatoes should be stored in a cool, dark and well-ventilated place, where they will keep fresh for up to ten days. Ideally, they should be kept out of the refrigerator in a cool, dry, dark place not above 60?F, which would fit the characteristics of a root cellar. Yet since most people don't have root cellars, we'd suggest just keeping your sweet potatoes loose (not in a plastic bag) and storing them in a cool, dark, and well-ventilated cupboard away from sources of excess heat (like the stove).
How to Enjoy
For some of our favorite recipes, click Recipes. [http://www.whfoods.com/recipestoc.php]
Tips for Preparing Sweet Potatoes:
If you purchase organically grown sweet potatoes, you can eat the entire tuber, flesh and skin. Yet, if you buy conventionally grown ones, you should peel them before eating since sometimes the skin is treated with dye or wax; if preparing the sweet potato whole, just peel it after cooking.
As the flesh of sweet potatoes will darken upon contact with the air, you should cook them immediately after peeling and/or cutting them. If this is not possible, to prevent oxidation, keep them in a bowl covered completely with water until you are ready to cook them.
A Few Quick Serving Ideas:
Purée cooked sweet potatoes with bananas, maple syrup and cinnamon. Top with chopped walnuts.
Steam cubed sweet potatoes, tofu, and broccoli. Mix in raisins and serve hot or cold with a curried vinaigrette dressing.
Desserts made with sweet potatoes are an autumn favorite but can be enjoyed year round. Try making sweet potato pie, bread, muffins or pudding.
Baked sweet potatoes are delicious even when served cold and therefore make a great food to pack in to-go lunches.
Safety
Sweet Potatoes and Oxalates
Sweet potatoes are among a small number of foods that contain measurable amounts of oxalates, naturally-occurring substances found in plants, animals, and human beings. When oxalates become too concentrated in body fluids, they can crystallize and cause health problems. For this reason, individuals with already existing and untreated kidney or gallbladder problems may want to avoid eating sweet potatoes. Laboratory studies have shown that oxalates may also interfere with absorption of calcium from the body. Yet, in every peer-reviewed research study we've seen, the ability of oxalates to lower calcium absorption is relatively small and definitely does not outweigh the ability of oxalate-containing foods to contribute calcium to the meal plan. If your digestive tract is healthy, and you do a good job of chewing and relaxing while you enjoy your meals, you will get significant benefits - including absorption of calcium - from calcium-rich foods plant foods that also contain oxalic acid. Ordinarily, a healthcare practitioner would not discourage a person focused on ensuring that they are meeting their calcium requirements from eating these nutrient-rich foods because of their oxalate content. For more on this subject, please see "Can you tell me what oxalates are and in which foods they can be found?" [http://www.whfoods.com/genpage.php?tname=george&dbid=48]
Nutritional Profile Introduction to Food Rating System Chart
The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents (similar to other information presented in the website, this DV is calculated for 25-50 year old healthy woman); the nutrient density rating; and, the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised. Read detailed information on our Food and Recipe Rating System.
Sweet potato, baked, with skin
1.00 each
77.00 grams
95.39 calories
Nutrient
Amount
DV
(%)
Nutrient
Density
World's Healthiest
Foods Rating
vitamin A
13107.70 IU
262.2
49.5
excellent
vitamin C
17.06 mg
28.4
5.4
very good
manganese
0.52 mg
26.0
4.9
very good
copper
0.26 mg
13.0
2.5
good
dietary fiber
3.14 g
12.6
2.4
good
vitamin B6 (pyridoxine)
0.25 mg
12.5
2.4
good
potassium
306.05 mg
8.7
1.7
good
iron
1.46 mg
8.1
1.5
good
World's Healthiest
Foods Rating
Rule
excellent
DV>=75%
OR
Density>=7.6
AND
DV>=10%
very good
DV>=50%
OR
Density>=3.4
AND
DV>=5%
good
DV>=25%
OR
Density>=1.5
AND
DV>=2.5%[/size]
References
Baybutt RC, Hu L, Molteni A. Vitamin A deficiency injures lung and liver parenchyma and impairs function of rat type II pneumocytes. J Nutr. 2000 May;130(5):1159-65. PMID:10801913.
Ensminger AH, Ensminger, ME, Kondale JE, Robson JRK. Foods & Nutriton Encyclopedia. Pegus Press, Clovis, California 1983.
Ensminger AH, Esminger M. K. J. e. al. Food for Health: A Nutrition Encyclopedia. Clovis, California: Pegus Press; 1986. PMID:15210.
Fortin, Francois, Editorial Director. The Visual Foods Encyclopedia. Macmillan, New York 1996.
Hou WC, Chen YC, Chen HJ, et al. Antioxidant activities of trypsin inhibitor, a 33 KDa root storage protein of sweet potato (Ipomoea batatas (L.) Lam cv. Tainong 57). J Agric Food Chem 2001 Jun;49(6):2978-81. PMID:13860.
Li T, Molteni A, Latkovich P, Castellani W, Baybutt RC. Vitamin A depletion induced by cigarette smoke is associated with the development of emphysema in rats. J Nutr. 2003 Aug;133(8):2629-34. PMID:12888649.
Suzuki K, Ito Y, Nakamura S et al. Relationship between serum carotenoids and hyperglycemia: a population- based cross-sectional study. J Epidemiol 2002 Sep;12(5):357-66 2002.
Terahara N, Konczak-Islam I, Nakatani M, et al. Anthocyanins in callus induced from purple storage root of Ipomoea batatas L. Phytochemistry 2000 Aug;54(8):919-22. PMID:13870.
Wallerstein C. New sweet potato could help combat blindness in Africa. BMJ 2000 Sep 30;321(7264):786. PMID:13850.
Wood, Rebecca. The Whole Foods Encyclopedia. New York, NY: Prentice-Hall Press; 1988. PMID:15220.
Ylonen K, Alfthan G, Groop, L et al. Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study. Am J Clin Nutr. 2003 Jun; 77(6):1434-41 2003.
Recipes [http://www.whfoods.com/recipestoc.php]
Oxalates [http://www.whfoods.com/genpage.php?tname=george&dbid=48]
Vitamin A [http://www.whfoods.com/genpage.php?tname=nutrient&dbid=106]
Vitamin B6 [http://www.whfoods.com/genpage.php?tname=nutrient&dbid=108]
vitamin C [http://www.whfoods.com/genpage.php?tname=nutrient&dbid=109]
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