Yams are tubers which have white, yellow, or purplish flesh that have very minimal sweetness. The characteristics of yams vary greatly than those of sweet potatoes though. For one, yams are only minimally sweet while sweet potatoes, particularly the orange-coloured ones, are very sugary in taste. Yams’ skin, too, look quite different as it is rough and scaly as compared to the thin and smooth skin of sweet potatoes. Yam plant is a perennial vine cultivated for its large, edible, underground tuber, which can reach up to 120 pounds in weight and 2 metres in length. They are one of the typical tropical crops requiring hot, humid climates and may cease to grow when the temperature dips below 68 degrees F. Yams are similar in appearance to sweet potatoes, however, they are not at all related to it. Important differences that distinguish them from sweet potatoes; yams are monocotyledons, larger in size, features thick, rough, dark brown to pink skin depending on the cultivar type. Sweet potatoes on the other hand are dicotyledons, relatively smaller size and posess very thin peel.
Prospects of Yam Production in Nigeria:
Health Benefits of Yam:
1. Heals Skin Diseases & Cures Respiratory Problems – Yam has been used as a traditional medicine in China, Korea and Japan for centuries as it contains allantoin, a cell proliferate that expedites the healing process when applied topically on ulcers, boils and other skin diseases. Its decoction is also known to stimulate and relieve bronchial irritation, cough and other respiratory problems.
2. Good Source of Vitamin B6 – Yam is a good source of vitamin B6 which is needed by the body to break sown a substance called homocysteine, which can damage blood vessels walls. High levels of homocysteine can also lead to heart attack despite having low levels of cholesterol.
3. Supports Female Endocrine System – Yam is particularly useful for menopausal women. It contains an enzyme that provides a natural alternative to hormonal replacement in women who have reached menopause.
4. Source of Antioxidants – Yam contains antioxidants which also have anti inflammatory properties. The beta carotene and Vitamin C in this tuber work well to get rid of cancer-friendly free radicals. Free radicals can damage the body in reaction with DNA, so the antioxidants work to reduce the damage caused by these free radicals. It is also an excellent food for those suffering from arthritis and asthma.
5. Low Glycemic Index Healthy Food – Diabetics can eat yam without worrying about the rise in blood sugar level. Glycemic index of a food reflects the food’s effects on a person’s blood glucose level. Fast glucose absorption is not desirable, so yam raises the blood sugar level slowly as compared to simple sugars and is therefore highly recommended as a low glycemic index healthy food.
6. Aids Digestion & Improves Bowel Habits – The dietary fibre present in yam reduces constipation and decreases bad cholesterol. It contains good amount of potassium which aids in healthy digestion and stimulates smooth muscle contraction in the stomach for proper bowel habits.
7. Increases Nutrient Absorption of the Body – Daily consumption of yam juice can increase nutrient absorption of the body. It also protects valuable enzymes needed by the body for healthier cells and maintains the good condition of the body. By drinking yam juice, all the vitamins and nutrients of it can be easily absorbed by the body in its liquid form.
8. Improves Cognitive Ability – Yams also have the ability to increase learning and memory capacity in the human brain. According to a study, people who consumed yam for 6 weeks regularly noticed a significant increase in the cognitive abilities of the subject mainly due to the antioxidant compound present in yams. It can also help to cure Alzheimer’s disease.
9. Cancer Deterrent – Yam can also be viewed as a cancer deterrent especially of colon cancer. The dietary fibre in this tuber prevents colon cancer by preventing toxic compounds in the food from adhering to the colon mucosa. Vitamin A in yam provides protection from lung and oral cavity cancer.
10. Source of Energy & Antioxidant – Yams contain complex carbohydrate and fibre which gradually slow the rate at which sugars are released and absorbed in the mainstream. Being high in fibre, yam keeps you full without putting on those extra kilos. Yams are also a good source of manganese, a mineral that aids carbohydrates metabolism and is very important for energy production and antioxidant defences.
11. Mediates Metabolic Functions – The vitamins present in yams mediate metabolic functions in the body. Carotenes are very essential to convert Vitamin A in the body. Vitamin A maintains healthy mucous membranes and skin. It also improves vision. Vitamin C in yams play an important role in anti-ageing, improves immunity, wound. Healing and bone growth.
12. Helps in RBC Production & Improves Blood Flow – The minerals present in yam also play major roles in the body. Copper is very useful for the production of red blood cells and improves blood flow in the body. Iron further improves the blood circulation in the body. Manganese is used by the body as a co-factor for the antioxidant enzyme, superoxide dismutase.
Skin Benefits of Yam:
13. Delays Ageing Signs – Yam has amazing anti-ageing benefits. It contains amazing skin-friendly nutrients like beta carotene Vitamin C, Vitamin B6 and antioxidants which can help to prevent wrinkles and other signs of ageing.
14. Stimulates Collagen – Production: It contains a high amount of antioxidants which protects the skin from harsh sun rays and environmental hazards. It stimulates the production of thee skin collagen and brings smoothness and elasticity to the skin. Yam also renews damaged skin and improves the appearance of the skin.
Face Packs: Boil some yam and leave aside to let it cool. Mash it properly and add a dollop of honey. Apply it all over the face and let it stay for 30 minutes. You can also soak your feet in the boiled water to calm and relax your feet. Cut slices of your yam and place them on your eyes. Tubers have natural bleaching properties which help to reduce stubborn dark circles and rejuvenate the eyes and treat wrinkles as well.
Hair Benefits of Yam:
15. Promotes Hair Growth – Yam is considered as an excellent source of natural health promoting compounds like antocyanins and beta carotene. It also contains Vitamin A which is highly beneficial for cell growth, including growth of hair. A deficiency in beta carotene can lead to dry, dull and lifeless hair which flakes off into dandruff.
16. Hydrates Scalp – Vitamin A in yam helps to produce and protect the oil in the scalp. This will keep the scalp hydrated and will prevent hair fall due to breakage.
17. Prevents Premature Hair Greying – Yam will also prevent premature greying as it contains a good amount of Vitamin B6 which creates melanin and gives the hair its colours.
18. Promote Blood Circulation in the Scalp – Iron in yam helps the red blood cells to carry oxygen and promote blood circulation in the scalps. Low levels of iron in the body can lead to hair loss and baldness in both men and women. Thus, regular consumption of yam will prevent hair loss and will promote hair growth.
Problems of Yam Production in Nigeria:
Though yams are rich in carbohydrates, they are very low in protein. A 100-gram yam provides just 1.5 grams. Protein is essential for building and maintaining body tissues, and research suggests that increasing protein intake may aid in dieting. Yams also contain virtually no fat. While this can be helpful if you’re following low-fat diet, it can also be a major drawback. Fat promotes satiety, ensures proper growth and development and helps your body absorb vitamins, so consuming too many yams at the expense of fat-containing foods can be detrimental.
Yams are very low in iron. Iron is an essential nutrient that helps ensure proper cell growth and is essential for the delivery of oxygen to the cells. With low consumption of iron, one can experience fatigue and a compromised immune system. Yams are also devoid of vitamin D, which is important because it supports the body’s absorption of calcium. The body needs calcium to maintain the strength of the bones and teeth, and chronic deficiency of vitamin D may increase the risk of osteoporosis. While yams offer a variety of vitamins, they do not offer any vitamin B-12. This vitamin is essential because it helps form DNA and red blood cells. Failure to consume enough vitamin B-12 can also result in anaemia, a condition in which the body doesn’t produce enough red blood cells.
Yams grow under the ground and so are naturally prone to diseases and infestation of pests and pathogens. Yams, too, may contain alkaloids that are toxic when ingested. These bitter alkaloids compounds also tend to accumulate in the flesh of young yellow and white yams. Yams contain oxalates and phytic acid as well. Oxalates crystallize in the body when in excess amounts so individuals with impaired kidney and/or bladder function should consult their doctor prior to incorporating this vegetable in their diet. Phytic acid, meanwhile is considered an anti-nutrient and binds with minerals like iron, zinc preventing the absorption of these desirable nutrients.
Yam is not an allergenic food and does not contain too much of oxalates or purines but precautions should be exercised while consuming. A small amount of oxalates can cause kidney damage therefore it is important to speak to a doctor in case of any kidney or gall bladder ailment. People who have a healthy digestive tract are better able to absorb the nutrients of yam without any side effects. There might be side effects like nausea, vomiting, headache and diarrhoea and it is important to seek medical attention if any of these side effects occur.