Water yam [Dioscorea alata] is a species of yam, a tuberous root vegetable. The tuber are usually bright lavender in color, water yam [Dioscorea alata] is one of oldest food crops so far. It belongs to the family of monocotyledonous plants. It originated from south-east Asia in Burma. From there it spreads to India, Malaysia, Indonesia and eastern part of south-east Asia It served as food for voyagers and was there by spread to parts of the tropics. Immigrations from India and Malaysia introduced it to Madagascar from where it was introduced into east Africa in the 16^th century. It was introduced to West African countries by the Portuguese and Spanish. Today, water yam is the most widely distributed of all the yams, being grown in all parts of the tropics. It is the most extensively cultivated species yam in the West Indies, the pacific Islands and tropical Asia. It is known as greater yam or ‘ten month yam. It can be found in some places in Nigeria It is called [Ewura] in Yoruba land, it is the main staple food in Ijebu area-western Nigeria. Yet most people do not consume it efficiently.

Water yam is planted within the months of March –April, late planting yield poorly. It mature in 8-10months and keeps better in storage than other species because they remain dormant for several months. It grows best at temperature between 25°C and 30°C. It requires soil that is well drained, of high fertility and high inorganic matter, hence loamy soil is best. It grows in a shorter time than the white yam and possesses a fibrous root system. Most of the roots occur in the top-soil, 30cm, above the soil level. The tubers vary considerably in shape and size, depending on the soil and how deep the ground in when planting.(udensi, 2008) They may occur singly or in groups, straight or branched which yam contains a higher proportion of water than either the white or yellow. Its loose or watery texture is readily noticeable when the tuber is cut or grated the tuber may be purple, white yellow; light brown or almost red in color when peeled. The leaves are distinctively different from other being heart-shaped long broad and winged at the petiole. The stems usually have no spines and they climb round the stakes in a counter- clockwise direction    

Dioscorea alata or water yam, a common staple food in Nigeria, has been used for more than 2000 years in traditional medicine to treat different systemic diseases including hypertension. Hypertension is the most common risk factor for conditions such as stroke, heart failure and heart palpitation. It is one of the world’s greatest public health problems. Although, many new antihypertensive drugs with improved efficacy have been introduced to the market, still possess serious side effects, on the one hand, nutrition and physical exercise are gaining more importance in the treatment of hypertension. Recent attention has focused on herbal and mineral preparations such as water yam, which are traditionally used as potential therapeutic agents, in the prevention and management of cardiovascular diseases such as diabetes and hypertension. Various varieties of water yam tubers are used as food as well as for medicinal purposes. It is generally believed that an intake of water yam may be beneficial to improve the function of spleen, stomach, kidney and lung. In folk medicine, water yam has been used as a laxative and worm expeller, and as a treatment for fever, gonorrhea, leprosy, tumor and inflamed hemorrhoids. Moreover, water yam may also help reduce irritability, and its anti- inflammatory benefits might offer relief of joint pain that often accompanies menopause because it contain a chemical, diosgenin, which is often promoted as a ‘’natural alternative ‘to estrogen therapy compounds in water yam may prevent muscle loss after menopause, according to a laboratory animal study published in the June 2008 issue of the Taiwan journal of obstetrics and gynecology.

In study, supplementation with 250miligrammes to 1,500miligrammes per kilogram of body weight per day of wild yam showed improved muscle function. By contrast, supplementation with diosgenin, the active component of wild yam, did not produce beneficial results for muscle function in this study. So it makes it useful in correcting, vaginal dryness in older women pm [premenstrual syndrome], menstrual cramps, weak bones [osteoporosis], increasing energy and sexual drive in men and women, and breast enlargement. Another interesting health benefit of water yam is its role in increasing fertilities while it used to be touted as an anti-fertility treatment and originally, birth control pills were made using these plants when taken in small does such as 10 to 20 drop daily from the first day of menstrual bleeding to the middle of the month. (Ovulation), it has actually been shown to increase fertility (Abdul 2013)

Further evidence suggests that water yam benefits stress and inflammatory conditions too. Its consumption can normalize the production of the adrenal cortex hormones. The anti-steer and anti-inflammatory hormones(natural steroidal hormones) help prevents inflammation and maintain joint and general structural integrity. This would explain the anti-arthritic, especially relating to rheumatoid arthritis and anti- rheumatics effects observed traditionally.

Water yam can show down the ageing process and boost the immune system for diabetics’ patients because it contains fiber, a substantial amount of antioxidants and vitamin C and helped to suppress blood sugar. Water yam belongs to the family of Dioscorea alata specie of yam, a tuberous root vegetable. High fiber content in water yam could be used to manage pile [hemorrhage] and constipation. The fresh root of water yam contain good amount of antioxidant and vitamin c. the vitamin in water yam play so many role in anti-ageing immune functions wound healing and bone growth. Also, it contain small amount of vitamin E and beta-carotene level. The tuber are in deeded one of the vegetable rich sources that has a lot of minerals, like copper, it has calcium, it contains potassium, iron and also phosphorus, these are all essential elements contained in the water yam. It suppresses the blood sugar because of the high fiber content. Also it is a good source of vitamin B complex and energy, among others she explained that anything had fiber could help to prevent constipation and also reduce pain for pile patients because when it comes to bowel movement, you have hard stool, but by the time you eat water yam, the stool softens because of the fiber content. The nutritionist also advised Nigeria to always eat local food for good health. Water yam are climbing plants with glabrous leaves and twining stems, which coil readily around a stake, they are perennial through root system but are grown as annual crops water yam [Dioscorea alata] is one of the most economically important yam species, which serves as a staple food for millions of people in tropic and subtropical countries [Hahn 1995].D.alata is popular and prevalent within Abakaliki agro ecological zone of Ebony state, Nigeria where it is called ‘Mbala or Nvula’[Igbo names].

They are consumed, boiled, roasted, fried or pounded and eaten in association with protein rich sauces. D. alata. Can also be processed into flour and reconstituted into fufu dough. Generally, they contain less sugar and have an extended shelf life [Raemackers, 2001], which ensure availability in periods of scarcity. Five high yielding and disease resistant water yam varieties developed by International Institute of Tropical Agriculture [IITA] and two landrace were evaluated within Abakaliki agro ecological zone [Oselebe and Okporie, 2005], most of these improved varieties showed remarkable potential for high yield over the landraces. Water yam can be eaten boiled, mashed, fried or mixed with palm oil or groundnut oil and steamed. Flour can also be made from it. Dishes such as Isikolo, pounded yam, Ikokore, pottage and fritters can be made from it. It can also be cooked with beans. Dishes such as queen cakes, biscuits and pastries can be prepared from water yam flour.