Tuber Crops - Sweet Potato

Importance and Scope

Sweet potato (Ipomoea batatas L. Lam.) is also believed to have originated in or around northern South America. It is a herbaceous, perennial plant, but is grown as an annual by vegetative propagation using either storage roots or stems cuttings. The tuber is an important source of carbohydrate. Certain varieties having yellow flesh are rich in carotene, a precursor of vitamin A. The edible sweet potato is variously referred to as a root, a root-tuber or a tuber. Sweet potato is a short duration crop, adaptable to a wide range of growing conditions. It exhibits no strict seasonality making it suitable as a combination crop with other crops.

Area and production

Sweet potatoes are widely grown throughout the world. It is grown in almost 111 countries, all over the world. Asia accounts for 78.7 per cent of the area under cultivation of which majority (67.7 percent) is accounted by China. As regards production, 93.1 per cent is accounted by Asia in which the contribution of China is 87.7 per cent. In India, sweet potato is grown in 0.14 million hectares with an annual production of 1.17 million tonnes at productivity of 8.3 t ha-1. The major sweet potato growing states in India are Orissa, Uttar Pradesh and Bihar. The crop is usually raised as a rainfed crop in kharif season and with supplemental irrigation during the rabi season. 

Climate and Soil requirements

Sweet potato is a warm weather crop and its growth is best at temperature around 24°C. Hence, it can be grown throughout the tropics, but in temperate regions, the aerial portion die out during winter. Warm sunny days and cool nights are very much favourable for storage root formation in sweet potato. Root formation requires cooler temperature (about 24 0 C mean temp.) while the weather should be warm for root bulking. Shading of the crop results in reduced tuber yield.

Sweet potatoes require at least 500 mm rainfall during the growing season and an annual rainfall of 750-1000 mm is considered the best. They can tolerate considerable periods of drought but yields are very much reduced if water shortage occurs at the time of tuber initiation. Sweet potatoes grown under high rainfall frequently produce vigorous vine growth but poor tuber yield. The ideal conditions for high yield are good rains during the period of early growth and dry sunny weather during the period of tuber bulking and maturity. Sweet potato can be grown on a wide variety of soils, but sandy loams, reasonably high in organic matter with permeable subsoil are ideal. On heavy clays, shoots and leaves grow well, but the yield is poor with tubers of irregular shape. Dry and compact soil favours lignification leading to the formation of pencil like roots and more vine growth. pH 5.6 to 6.6 of the soil for sweet potato cultivation is optimum. Sweet potato is an acid tolerant crop it cannot withstand salinity and alkalinity. Salinity significantly reduces growth of stems and roots and results in lateral rolling of leaf lobules, reduction in leaf size and necrosis of older leaves.

Botany 

Sweet potato is a hexaploid species with 90 somatic chromosomes. It is a perennial herb with trailing vines and with a cluster of a few medium sized tubers. For cultivation purpose, it is treated as an annual with duration of 90 to 120 days. Though plants produce viable seeds, highly heterozygous nature of the crop results in a heterogeneous population. Hence stem cuttings are used for propagation purpose. Sweet potato has an extensive fibrous root system both at stem cuttings and at nodes touching soil. Some roots act as storage organs for storing reserve food. Storage roots may be fusiform, spindle or globular in shape and surface is smooth. Skin has white, red or light copper colour. Flesh may be white or with different combinations of orange and red. Leaves are simple, alternate and stipulate. They vary in size and shape, occasionally in same plant. Shape varies from ovate to cordate, hastate or deeply lobed and may change on ageing. Leaf shape is an important character for identifying clones. All clones do not flower and in flowering ones, duration and initiation of flowering vary. Flowers are axillary and borne solitary or in simple cymes. Flowers are bisexual. Corolla is attractive and funnel shaped formed by fusion of five petals. Anthesis starts before dawn and closes by 9-11 a.m. Pollination is entomophilies. Fruit is a capsule with false septa. Seed coat is hard and impervious to water. Hence, scarification is required for promoting germination.

Varieties

Varieties Sweet potato varieties differ in shape, size and colour of leaves, tubers and nature of tuber flesh. A number of local cultivars like Badrakali chuvala, Chakkaravalli, Anakomban and Kottaram chuvala are grown in Kerala. The Central Tuber Crops Research Institute (CTCRI), Thiruvananthapuram developed quite a good number of varieties and a brief description of them is given below: 

Varsha: A semi-spreading hybrid with reddish purple skin, light yellow flesh and excellent cooking quality; yield 18-22 t/ha in 120-125 days. 

Sree Nandini: A spreading variety with light cream skin, white flesh and good cooking quality; yield 20-25 t/ha in 100-105 days.

Sree Vardhini: A semi-spreading variety with purple skin, light orange flesh and high carotene content (1200 I.U.); yield 20-25 t/ha in 100-105 days. Tolerant to Feathery mottle virus. 

Sree Ratna: A spreading variety with purple skin, orange flesh and excellent cooking quality; yield 20-26 t/ha in 90-105 days. 

Sree Bhadra: A semi-spreading variety with light pink skin and cream flesh; resistant to root knot nematode; yield 20-27 t/ha on 90-95 days.

Sree Arun: A spreading variety with pink skin, cream flesh and good cooking quality; yield 20- 28 t/ha in 90-100 days. 

Sree Varun: A spreading variety with cream skin, cream flesh and good cooking quality; yield 20-28 t/ha in 90-100 days.

Sree Kanaka: The variety is developed by Central Tuber Crop Research Institute (CTCRI), Sreekariyam. It has cream color skin tuber which has dark orange color inner flesh. It gives an average yield of 41-62.5 qtl/acre.

The Kerala Agricultural University developed an improved variety, Kanjangad, yielding 12.39 t/ha. Purple coloured and spindle shaped tubers have yellow soft flesh. It is tolerant to shade and weevil incidence.

Pusa Sunheri: A brown skinned variety with yellow flesh rich in carotene; boiled flesh is attractively orange yellow. Acharya Ranga Agricultural University, Hyderabad developed following improved varieties: 

Cross-4: Yield 20-30 t/ha in 90-105 days; highly susceptible to weevil infestation.

Rajendra Shakarkand-5: Yield 30 t/ha in 105-120 days; Resistant to Fusarium wilt and Cercospora leaf spot disease. 

Kalmegh: A short duration variety (90 days) yielding 26 t/ha.

Co.1 and CO.2: Tamil Nadu Agricultural University has developed two varieties viz., Co.1 and CO.2 yielding 26 t/ha and 32 t/ha, in 135 days and 110-115 days, respectively 

IARI, New Delhi released two improved varieties viz., Pusa Safed, and Pusa Sunheri. Pusa Safed: A white skinned variety with white flesh

Preparation of cuttings

The cuttings should be 10-15 cm in length with 2-3 nodes and to be collected from matured vines aged 3 months and above. Dip the vine cuttings in a solution by mixing 400 g of Azospyrillum in sufficient quantity of water.

Sowing

Time of sowing

For optimum yield, tubers should be sown in nursery beds in the month of January to February and the optimum time for planting vines in the field is in the month of April to July.

Spacing

Use row to row spacing of 60cm and plant to plant spacing of 30cm

Sowing depth

Use depth of 20-25cm for tuber planting.

Method of sowing

Mainly propagation is done by tubers or vine cuttings. In vine cutting method (commonly used), the tubers are taken from the old vines and planted on prepared nursery beds.  Mainly vines are planted in ridges or on prepared flat beds. It is seen that terminal cuttings gives better result. The host plant must have at least 4 nodes. Row spacing of 60cm and within row spacing of 30cm is used. Before planting it is better to treat the cuttings with DDT 50% solution for 8-10 minutes.

Planting system

The land is ploughed or dug to a depth of 20 cm and harrowed to pulverize the soil. Mounds, ridges and furrows and flat bed methods of planting are being practised in different locations. It is preferable to plant sweet potato on mounds in areas experiencing problems of drainage. Ridges formed across the slope are recommended in slopy lands to prevent soil erosion. Among the different methods of land preparation, the highest tuber yield was obtained when planted on mounds. The higher yield obtained in mound system of planting is attributed to better soil aeration and less tendency for soil compaction.

The cuttings are planted in the soil with both the ends exposed and the middle portion buried in the soil. Vines are also planted in an inclined position with half of its length buried in the soil. The number and weight of total and marketable tubers are higher when slips are planted horizontal to the soil with 5 or 6 nodes covered than when planted perpendicular to the soil. Horizontal planting also results in higher plant survival and better development of the root system.

Plant the terminal vine cuttings (80,000/ha) at 20 cm spacing.

Irrigation

To ensure proper sprouting and establishment of vines, a moist seedbed is required for 4-5 days. When sufficient soil moisture is not available at planting, irrigation has to be provided daily for the first three days followed by irrigation on alternate days for one week. The tuber initiation phase, which falls around 20 days, is very critical and maintaining optimum soil moisture during this period is essential to obtain economic yield. Irrigation would generally increase the yield and improve the grade and quality of marketable tubers.

When grown as irrigated crop, provide irrigation once in 2 days for a period of 10 days after planting and thereafter once in 7-10 days. Stop irrigation 3 weeks before harvest. But one more irrigation may be given 2 days before harvest.

Organic manuring

As sweet potato removes appreciable quantities of plant nutrients, incorporation of considerable amount of organic manure at planting has been recommended to maintain soil productivity. Application of 5-10 t ha-1 FYM is advocated.  If 20 kg/ha Azospirillum is applied.

Weeding

Sweet potato vines are so aggressive that they cover the soil surface quickly and suppress most of the weeds. However, weeds are a problem in the early stages of the crop and keeping the field weed free at this stage is recommended.

After cultivation

The field should be kept clean by hand weeding till vines are fully developed. Earthing up can be done on 25th, 50th and 75th day after planting. The vines are lifted and turned on 50th and 75th day after planting but before earthing up to prevent root formation at nodes and to make the originally formed roots larger. Spray Ethrel five times at 250 ppm at fortnightly intervals commencing from 15 days after planting.

Rotation and mixed cropping

Under irrigated conditions, sweet potato can be rotated with rice and planted during December-January after harvest of the second crop of rice. As a mixed crop, it can be grown along with colocasia, amorphophallus etc. Under rainfed conditions, green manure crops such as kozhinjil and sannhemp can be grown after harvest of the sweet potato and later incorporated into the soil at the time of land preparation for the succeeding crop.

Health Benefits of Sweet Potatoes, According to Science

Sweet potatoes are nutritious and delicious root vegetables. The sweet potato is creamy and soft enough to be an ingredient in several pie recipes, and most people think of the vegetable as merely a dessert ingredient. However, scientists have found that sweet potatoes are among the best sources of Vitamin A. Sweet potatoes are also naturally packed with vitamin B5, riboflavin, niacin, thiamin, and carotenoids due to their naturally orange color.

The sweet potato, also known as the Ipomoea batatas, not only contains many nutrients, but it is also packed with medicinal benefits. Scientists have determined that sweet potatoes contain anti-inflammatory, anti-diabetic, and anticancer properties. Most sweet potatoes are orange in color, but there are others that come in purple, yellow, white, pink, and red. The following are some of the health benefits that you can accrue from including sweet potatoes in our regular diet.

Sweet potatoes help prevent Vitamin A deficiency

Vitamin A deficiency is a serious issue especially in developing nations around the world. The health repercussions of a vitamin A deficiency are grave and can include decreased resistance to infectious disease, increase in infectious morbidity, dry eyes as well increased mortality for both pregnant and lactating women and their children.

Sweet potatoes are an extremely important source of Vitamin A because they contain high levels of beta-carotene. Beta-carotene is transformed into vitamin A in our livers, with every molecule of beta-carotene producing two molecules of Vitamin A.

Bottom Line: Sweet potatoes are a natural and abundant source of beta-carotene and Vitamin A. Vitamin A is essential in helping the body fight off infections, and remain resistant to any further infections.

Sweet potatoes can also help manage diabetes

Sweet potatoes are categorized as low to high on the glycemic index scale, and several studies have indicated that it can minimize the occurrence of insulin resistance and low blood sugar levels, as well as high blood sugar in people who are suffering from diabetes.

Their relatively low glycemic index means that the sweet potatoes release sugar into the bloodstream slowly, unlike other starchy foods. This steady release of sugar is what aids in controlling the blood sugar levels of individuals so that it does not go low or high. Thus, the sweet potatoes can be used in the regulation of blood sugar levels especially in people with diabetes. This regulation is witnessed in both types of diabetes, i.e. type I and type II.

Studies into the varieties of sweet potatoes have revealed that the Beauregard is the most effective sweet potato variant when it comes to blood glucose regulation. In addition, the variant has been shown to have similar protein patterns to Caiapo, which is an extract from white sweet potatoes. Caiapo has been documented as improving the glucose and cholesterol levels of individuals with type II diabetes, and is thus used as dietary management of this disease.

The fiber in the sweet potato is also hypothesized to be beneficial for diabetes management. The sweet potato is a high fiber food, which has been shown to lower the blood sugar levels of individuals suffering from type I diabetics. 10-15% of the fiber in a sweet potato consists of soluble fibers such as pectin, which are effective in reducing food consumption and spikes in blood sugar.

Approximately 77% of the fibers in sweet potatoes are insoluble, and the have their own role to play in the fight against diabetes. Insoluble fibers are essential in promoting insulin sensitivity, which then helps in regulating the amount of sugar in the blood.

Furthermore, sweet potatoes are an important source of magnesium, which has also been shown to minimize the risk of individuals developing type II diabetes.

Bottom Line: Sweet potatoes contain essential fibers and magnesium that are critical in the prevention and management of diabetes. The vegetables also have a moderately low glycemic index that also aids in the regulation of blood glucose levels.

Sweet potatoes can help manage stress levels

Sweet potatoes contain a significant amount of magnesium, which is an essential mineral for normal body functioning . One of the most important benefits of magnesium is that it helps reduce stress and anxiety. Studies have shown that an increase in magnesium deficiency in modern diets has resulted in a significant increase in the cases of depression reported across the world. For instance, some controlled studies have indicated that magnesium deficiency increases depression in women experiencing premenstrual symptoms.

Magnesium deficiency and depression are linked because they both feature cell-mediated immune responses and bodywide inflammation. Studies done on animal models have shown that an increase in magnesium intake protects the brain from anxiety and/or depression after a traumatic injury. Furthermore, studies on animal models have shown that a decrease in magnesium will result in an increase in anxiety-related behaviors as well as depression in mice.

In addition, magnesium has been found to reduce insomnia in older individuals. Insomnia is a trigger for stress, depression, and anxiety, which is unfortunate as more than 50% of elderly people suffer from some form of lack of sleep.

Bottom Line: Sweet potatoes are an important source of magnesium, whose deficiency has been reported to be linked with a higher risk of depression, stress and anxiety. Thus, sweet potatoes can replenish the body’s magnesium levels and help alleviate the symptoms of depression and anxiety-related behaviors in individuals.

Sweet potatoes contain anti-inflammatory activity

Sweet potatoes contain a significant amount of vitamins, most of which have powerful anti-inflammatory properties. Studies carried out on the purple sweet potato have conclusively shown that the extracts from the vegetable variant had the capability of inhibiting the production of active inflammatory components in the body.

Furthermore, sweet potatoes have a high concentration of choline, which is a very versatile nutrient. One of the main benefits of choline is that it reduces inflammatory responses in the body resulting in less inflammation. Studies on animal models have shown that choline is effective in therapeutically restraining incidences of systemic inflammation in the body.

Other studies have indicated that extracts from the purple sweet potato contained anthocyanins, which proved essential in reducing and preventing inflammation in colon cancer cells as well the reduction of cell proliferation in specific cancer cells.

Bottom Line: The presence of anthocyanins and choline in sweet potatoes make the vegetables an essential dietary source in the prevention and reduction of chronic inflammation in the body.

Sweet potatoes can help protect/prevent/manage cancer

Studies have also shown that the purple-fleshed sweet potato is especially effective in the fight against cancer. This variation of the sweet potato has elements that are able to inhibit growth of specific cancers that include breast cancer, gastric cancer, and colon cancer by inducing the cell death of these cancer cells. The vegetable’s high anthocyanin content is believed to be the reason behind the sweet potato’s anti-cancer activity when it comes to gastric and breast cancers.

Other studies have conclusively shown that extracts from different parts of the sweet potato can also induce cell death in prostate cancer cells, ensuring that the cancer does not grow and spread to other parts of the prostate. Scientists have concluded that the anti-cancer activity of sweet potatoes when it comes to controlling prostate cancer is due to their high polyphenol content.

The presence of carotenoids such as beta-carotene in sweet potatoes has also been reported as having a significant effect on reducing the risk of men becoming afflicted with prostate cancer.

Beta-carotene has also been found to be effective in preventing and reducing the risks of individuals developing colorectal cancer.

Bottom line: Sweet potatoes contain beta-carotene, a carotenoid, which is essential in protecting men from developing prostate cancer. In addition, extracts from different parts of sweet potatoes have been shown to accelerate the death of breast, gastric, colorectal, and prostate cancers, limiting the growth and spread of these cancers.

Sweet potatoes can help guard against ulcers

An ulcer occurs when an inflamed tissue is shed from the mucous membrane or from the skin, and it can be quite painful. Studies on animal models have shown that the methanol extract from the root of a sweet potato can protect the gastrointestinal tissues from aspirin-induced ulcers. The results of these studies have proved that the sweet potatoes can be used in the treatment and management of peptic ulcers.

Another study showed that the flour in the roots of the sweet potatoes helped in the prevention of ethanol-related ulceration in the stomach in animal models. The flour from the vegetable is reported to suppress gastric ulceration b reducing swelling in the surrounding tissues, and protecting the gastric wrinkles.

In addition, extracts from the vegetable have been shown to have free radical scavengers, which are important in the healing of wounds inside the body.

Bottom Line: Studies on the extracts from sweet potatoes have shown that the vegetable has chemicals that can help heal wounds and ulcers in the stomach. Thus, dietary consumption of sweet potatoes can be an effective treatment plan against major types of ulcers including ethanol and aspirin-induced ulcers.

Sweet potatoes can help in minimizing the risk of cardiovascular diseases

Oxidation in the body results in complications such as atherosclerosis, which in turn can lead to the development of a number of cardiovascular diseases. Leaf extracts from sweet potatoes were tested and scientists found that the high levels of polyphenols in the leaf extracts were able to suppress oxidation in humans, decreasing the chances of development of cardiovascular disease.

Scientists believe that the leaves of the vegetable have considerable antioxidant properties because of their relatively high levels of radical scavenging activity, as well as a high amount of polyphenol compounds. The scavenging activity and the high levels of polyphenols contribute to its antioxidant properties and help in minimizing the risk of one developing a cardiovascular disease.

Other scientific studies have shown that the high levels of anthocyanin in the purple-fleshed sweet potato contributed to the vegetable’s ability to reduce the chances of coronary disease.

In addition, sweet potatoes contain soluble dietary fibers, which have been strongly linked to reduced risk of cardiovascular diseases.

Bottom Line: The fibers, anthocyanin, polyphenols, and high radical scavenging activity contained in sweet potatoes are all important in the fight against cardiovascular diseases.

Sweet potatoes contain antimicrobial properties

Despite the fact that studies on the antimicrobial properties of sweet potatoes are limited, a number of scientific reports have concluded that the sweet potato does have some level of antimicrobial activity. Some studies have found that the ethanol and acetone extracts from sweet potato leaves possess antimicrobial properties against bacteria that cause pneumonia, and typhoid.

The fiber in sweet potatoes has also been documented to inhibit the growth of foodborne bacteria.

Other studies have found that sweet potato leaf powder, and its water, ethanol, and peptone extracts possess antimicrobial activity against Salmonella typhi, E.coli, and Klebsiella pneumoniae.

Bottom line: Sweet potatoes and their extracts possess antimicrobial activities, which can be used in the prevention and treatment of a variety of bacterial pathogens and infections.

Sweet potatoes can help improve hair and skin

As mentioned above, sweet potatoes are rich in vitamin A. The vegetables are also rich in Vitamin C and Vitamin E.

Studies have shown that dietary consumption or supplementation of Vitamin E has the potential of significantly increasing hair numbers in individuals who are suffering from hair loss. This is because Vitamin E contains antioxidant properties that help reduce oxidative stress, a major cause of alopecia.

Vitamin C has been known to be an effective dermatological treatment that can be used in the treatment of photoaging and hyperpigmentation. Vitamin C is also effective at neutralizing the oxidative stress caused by exposure to UV light. In addition, the combination of Vitamin C and E can significantly reduce the risk of skin cancer in individuals. Vitamin C is also essential in the synthesis of collagen, which is the main structural protein of the skin. A number of studies have also shown that Vitamin C contains anti-inflammatory properties. This means that the vitamin can help manage skin diseases such as acne, as well as promoting healing of wounds on the skin.

Vitamin A has been proven to be effective in the treatment and management of sun-damaged skin. In addition, the studies have shown that the vitamin is also effective in the treatment of skin cancer along with chemotherapy, and other treatment solutions.

Other studies have shown that Vitamin A is an effective stimulant of collagen, making it useful in decreasing the rate of natural cell aging as well as inhibiting photoaging of our skin.

Bottom Line: Sweet potatoes contain high levels of Vitamin A, C, and E, all of which are useful in the promotion of proper skin and hair health. These vitamins are useful in repairing skin that is damaged due to exposure to UV light. The vitamins also slow down the cell aging process in the skin helping you retain a youthful look for longer. In addition, vitamin E is especially useful in the prevention and treatment of alopecia, and maintaining good hair health.

Sweet potatoes are good for digestion

Sweet potatoes contain large amounts of fibers, which have long been known for improving the health of the gut as well as digestion. Many laxatives in use today are made from fibers, meaning that consumption of sweet potatoes can increase your intake of fibers needed to promote proper digestion. The high fiber content of the sweet potatoes can also aid in preventing constipation in both children and adults.

Bottom line: Sweet potatoes contain significantly high amounts of fibers, which are essential in promoting a well-functioning digestive tract, as well as preventing constipation.

Sweet potatoes can help in regulating blood pressure

Sweet potatoes can help in controlling blood pressure because they are rich in both magnesium and potassium. Studies have shown that a higher intake of potassium results in a decrease in blood pressure, which then significantly reduces the chance of an individual developing a stroke or a coronary problem.

Magnesium is also considered an effective dietary component in the prevention of hypertension, as well as its reduction in both pregnant and non-pregnant patients. In addition, other studies have found that magnesium deficiency in the body increases the risk factors for the development of hypertension.

Bottom Line: Sweet potatoes contain considerable amounts of both magnesium and potassium, both of which are essential in the fight against hypertension. They also help regulate the blood pressure, which reduces the chances of individuals suffering from cardiovascular diseases.

Sweet potatoes can boost fertility

The high doses of Vitamin A in sweet potatoes makes the vegetable ideal for consumption by women of childbearing age to enhance their fertility. Studies on animal models have shown that Vitamin A plays an integral role in improving reproductive performance. Research has also shown that a deficiency in Vitamin A can lead to secondary infertility in women of childbearing age.

Sweet potatoes also contain a healthy dose of iron, which is a crucial mineral in promoting fertility in women of childbearing age. Reports indicate that anaemia, or iron deficiency, is a cause of infertility among women. These reports have shown that treating the iron deficiency by increasing dietary intake of iron usually results in women being able to conceive a few months to a year after the treatment. Other studies have found that an increase in dietary iron intake reduces the risk of ovulatory infertility.

Bottom Line: Iron is essential in the promotion of fertility amongst women. An important source of dietary iron is sweet potatoes. Studies have shown that an increase in dietary intake of iron from food sources such as sweet potatoes can help reverse secondary fertility, as well as reduce the chances of women ending up suffering from ovulatory infertility.

In addition, sweet potatoes contain high doses of vitamin A, which is essential in improving reproductive performance in women of childbearing age.

Sweet potatoes are important for good vision

Sweet potatoes contain a lot of vitamin A, and most of us know that vitamin A is good for our vision, but we may not know in exactly which way the vitamin improves our vision. Studies have shown that the vitamin is essential in the formation of the pigments responsible for light absorption. In addition, vitamin A is also essential in maintaining the proper structure of the retina. A deficiency of vitamin A can result in poor vision, and in some instances blindness. Deficiency in the vitamin can also lead to night blindness.

Furthermore, other eye diseases including the dryness of the cornea, the ulceration of the cornea, and conjunctiva, have also been linked to a deficiency in vitamin A.

Sweet potatoes are also a significant source of both Vitamin C and E. A study carried out in India showed that there was a significant relationship between Vitamin C deficiency and the development of cataracts. Other studies have found that both vitamin C and E could be effective in the fight against oxidative stress, which most often leads to eye cataracts.

Bottom Line: Sweet potatoes contain high amounts of vitamin A, C, and E, all of which are integral in promoting good vision. Deficiency of vitamin A results in night blindness, total blindness, as well as malformation of the retina. Deficiency in vitamin C is mostly associated with the development of cataracts.

Sweet potatoes can help in weight management

Sweet potatoes contain soluble and fermentable fiber that increase satiety and offers the body a natural, self-sustaining mechanism for body weight regulation. Studies have shown that one of the major soluble dietary fibers in sweet potatoes, pectin, is effective at reducing food intake , reducing weight gain, and also increasing the activity of satiety hormones in the body.

Scientific studies have also shown that a higher intake of fibers is strongly correlated to reduced body weight. An increase in consumption of sweet potatoes will result in an increase in fiber intake, which will in turn, lead to a lower body weight.

Bottom line: The fiber in sweet potatoes can help in maintaining satiety, as well as reducing the overall weight of an individual. The more full you feel throughout the day, the less you will snack, which will help you manage your weight effectively.

Sweet potatoes are also memory-enhancing foods

Anthocyanin contained in the purple sweet potato possess memory enhancing properties. The underlying belief here is that the antioxidant properties of the anthocyanins are what make sweet potatoes memory enhancing agents.