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Uncooked potatoes can be toxic (they are the same family as deadly nightshade - although so too are tomatoes, and they can be eaten raw).
Solanine poisoningSymptomsSolanine poisoning is primarily displayed by gastrointestinal and neurological disorders. Symptoms include nausea, diarrhea, vomiting, stomach cramps, burning of the throat, heart arrhythmia, headache and dizziness. Hallucinations, loss of sensation, and paralysis, fever, jaundice, dilated pupils and hypothermia have been reported in more severe cases.In large quantities, solanine poisoning can cause death. One study suggests that doses of 2 to 5 mg per kilogram of body weight can cause toxic symptoms, and doses of 3 to 6 mg per kilogram of body weight can be fatal.Symptoms usually occur 8 to 12 hours after ingestion, but may occur as rapidly as 30 minutes after eating high-solanine foods.Correlation with birth defectsSome studies show a correlation between the consumption of potatoes suffering from late-blight (which increases solanine and other glycoalkaloid levels) and the incidence of congenital spina bifida in humans. However other studies have shown no correlation between potato consumption and the incidence of birth defects. Solanine in potatoesSolanine occurs naturally in all nightshades, including tomatoes, capsicum, tobacco and eggplant, as well as plants from other species. However the most ingested solanine is from the consumption of potatoes.Potatoes naturally produce solanine and chaconine, a related glycoalkaloid, as a defense mechanism against insects, disease, and predators. Potato leaves and stems are naturally high in glycoalkaloids.When potato tubers are exposed to light, they turn green and increase glycoalkaloid production. This is a natural defense to help prevent the uncovered tuber from being eaten. The green colour is from chlorophyll, and is itself harmless. However, it is an indication that increased level of solanine and chaconine may be present.Some diseases, such as potato blight, can dramatically increase the levels of glycoalkaloids present in potatoes. This is believed to be a natural reaction of the plant in response to disease and damage.Commercial varieties of potatoes are screened for solanine levels, and most have a solanine content of less than 0.2mg/g. However potatoes that have been exposed to light and started to green can show concentrations of 1mg/g or more. In these situations a single unpeeled potato can result in a dangerous dose.AvoidanceSolanine and chaconine are present in potato shoots. In potato tubers 30–80% of the solanine develops in and under the skin and thus may be removed by peeling and removing the eyes. This is advisable if the tubers show green, but is not a guarantee of safety. Potato greening strongly suggests solanine build-up although each process can occur without the other. A bitter taste in a potato may be a more reliable indicator of toxicity.Deep-frying potatoes at 170° C (306° F) will effectively lower glycoalkaloid levels, but microwaving is only somewhat effective and boiling is not.
Potatoes contain glycoalkaloids, toxic compounds, of which the most prevalent are solanine and chaconine. Cooking at high temperatures (over 170 °C or 340 °F) partly destroys these. The concentration of glycoalkaloid in wild potatoes suffices to produce toxic effects in humans. Glycoalkaloids occur in the greatest concentrations just underneath the skin of the tuber, and they increase with age and exposure to light. Glycoalkaloids may cause headaches, diarrhea, cramps and in severe cases coma and death; however, poisoning from potatoes occurs very rarely. Light exposure also causes greening, thus giving a visual clue as to areas of the tuber that may have become more toxic; however, this does not provide a definitive guide, as greening and glycoalkaloid accumulation can occur independently of each other. Some varieties of potato contain greater glycoalkaloid concentrations than others; breeders developing new varieties test for this, and sometimes have to discard an otherwise promising cultivar.Breeders try to keep solanine levels below 0.2 mg/g (200 ppmw). However, when even these commercial varieties turn green, they can approach concentrations of solanine of 1 mg/g (1000 ppmw). Some studies suggest that 200 mg of solanine can constitute a dangerous dose. This dose would require eating 1 average-sized spoiled potato or 4 to 9 good potatoes (over 3 pounds or 1.4 kg) at one time. The National Toxicology Program suggests that the average American consumes at most 12.5 mg/person/day of solanine from potatoes. Dr. Douglas L. Holt, the State Extension Specialist for Food Safety at the University of Missouri - Columbia, notes that no reported cases of potato-source solanine poisoning have occurred in the U.S. in the last 50 years and most cases involved eating green potatoes or drinking potato-leaf tea.Solanine is also found in other plants, in particular the deadly nightshade. This poison affects the nervous system causing weakness and confusion.
Food plants species in the Cruciferae (Brassicaceae) family contain substances called glucosinolates, which probably play a role in the plant's defenses against predators and fungal attack. When eaten by animals or humans, glucosinolates can inhibit thyroid gland functioning, causing enlargement and atrophy of the thyroid, or goiter.Brassica species containing goitrogens include cabbage, broccoli, cauliflower, rutabaga, kohlrabi, and the oilseeds, rapeseed and canola. The enzymes required for production of goitrogens in the plant are destroyed by cooking. Goitrogens are also lost through leaching into cooking water.Effects in AnimalsFeeding rapeseed meal with high glucosinolate levels to animals and poultry induces enlarged thyroids, reduced circulating thyroid hormones, liver, kidney, and adrenal abnormalities, and poor growth and reproductive performance.Effects in HumansOne study showed no ill effects when volunteers ingested 40 mg goitrin/day in Brussels sprouts over a 4-week period. Another study showed inhibition of iodine uptake after administration of 50-200 mg of goitrin. Studies in Great Britain estimated an average intake of 76 mg glucosinolate per person per day, with a range of up to 200 mg per day. Whether or how much the consumption of Brassica vegetables contributes to ill health in humans is unknown. The cause of endemic goiter in certain geographic regions may be the result of the interaction between iodine deficiency and certain food components, such as glucosinolates.Many nutritional studies have shown that dietary fruits and vegetables, including those in the Brassica group, have a protective effect against certain cancers. In animal studies, glucosinolates and their breakdown products have inhibited tumor formation, although this anti-carcinogenic effect depends on the study design, the type of cancer being studied, whether other dietary components are present, and the timing of the administration of the glucosinolate compound.In summary, glucosinolates are known to be goitrogenic in animals, but their role in inducing goiter in humans is less clear. They can be anti-carcinogenic and cancer-promoting, depending on the species and circumstances of administration. In general, dietary vegetables, including Brassica vegetables, are beneficial in cancer prevention.
Protease inhibitors interfere with the action of trypsin and chymostrypsin, enzymes produced by the pancreas to break down ingested proteins. They are found to some extent in cereal grains (oats, barley, and maize), Brussels sprouts, onion, beetroot, wheat, finger millet, and peanuts. They have caused pancreatic hypertrophy in chicks and rats, but no ill effects have been observed in calves, pigs and dogs.Raw soybeans have high levels of trypsin inhibitors. Soybean fractions high in trypsin inhibitors depressed the growth of rats, chicks, and mice. Cooking heat largely destroys the trypsin inhibitors in soybeans, but 5 to 20% of the original trypsin inhibitor activity may be retained in commercially available soybean food products. For example, while raw soy flour contains 52.1 TI (trypsin inhibitor activity) per gram of sample, toasted soy flour contains 3.2-7.9 TI per g.
HAve you tried one!! sliced washed etc. Has a nice earthy flavor.. They are nice.. LOL Maybe I like dirt too! LOL