Talking about cancer causing factors, somatic and environmental factors are two of the major causes. Diet adds about 35% of the entire somatic and environmental causes. There are many foods that plays a significant role in cancer prevention and in slowing down the progression of cancerous cell lines.
In these, there are many vegetables that can perform a potent character in the cancer prevention and management along with potential cancer treatment. Studies have revealed that people who consume high amounts of fruits and vegetables have lower risk of developing many cancers. The reason behind this is the presence of phytoconstituents in them.
In this class of anti cancer vegetables, African leafy vegetables also made a significant space. According to the research published in the Journal of Nutrition and Dietetics, the African leafy vegetables exhibits considerable anticancer properties which aids in lowering the risk of cancer including cytotoxic and antioxidant effects. Their chemopreventive properties are credited to bioactive secondary metabolites.
The African leafy vegetables that show anticarcinogenic effects include:
- Ethiopian kale (Brassica carinata)
- Amaranth (Amaranthus retroflexus)
- Mustard (Brassica juncea)
- Sweet potato (Ipomoea batatas)
Ethiopian kale (Brassica carinata):
It is a leafy vegetable, which is consumed in the East African. It comes from the Brassicaceae family that contains several bioactive compounds, which present numerous benefits to health. It is always better to cook the vegetable before eating to eliminate the bitter taste. Though, overcooking may considerably decrease the phytochemical constituent.
In cancer prevention, this vegetable plays a significant role as it possesses potent anti-apoptotic and aids in improving the activities of certain enzymes which further helps to regress the progression of cancerous cells.
The efficacy of this leafy vegetable can be seen via a randomized control study, in which people who consumed 15 g of Ethiopian Kale for five days shows significant improvement in the activities of enzyme , which associated with liver cancer prevention.
Amaranth (Amaranthus retroflexus):
Amaranths species are known worldwide for their various health benefits. Almost every part of amaranth plant has health benefits. For example, the extracts of their leaves show benefits in case of constipation and the extracts when applied on the skin can show radioprotective properties.
Along with its other health benefits, amaranth also possess potential chemopreventive properties. Its free radical scavenging property due to phytochemicals like β-carotene, vitamin C, tocopherol, and riboflavin aids in neutralizing the free radicals formation, modulating environmental toxicants, preventing fibrosis, inhibiting lipid peroxidation, enhancing antioxidant status and lowering the alkaline phosphatase activity.
All these actions led by the phytoconstituents of this vegetable helps in chemoprevention.
Mustard (Brassica juncea):
This plant is grown in South- Africa. The mustard leaves have medicinal benefits. They are found to hinder the growth and stimulate the apoptosis in cancer cells. The process of angiogenesis is needed for cancer to spread to other tissues. The mustard leaf extracts repress the angiogenesis in cancer cells. They contain glucosinates and isothiocyanates, which are the bioactive phytochemicals responsible for its chemopreventive effect.
Sweet potato (Ipomoea batatas):
The leaves of this vegetable are loaded with vitamin B, β-carotene, calcium, zinc and iron. This vegetable has polyphenolic compounds that show antimutagenic activity. Sweet potato leaves also contain lutein, which is responsible for quenching singlet oxygen that can cause damage to DNA, leading to the formation of cancer cells.
Other than these vegetables, some of the other African leafy vegetables can also shows significant properties in cancer prevention. These are:
- Cowpeas (Vigna unguiculata)
- Spider Flower (Cleome hassleriana)
- Black nightshade (Solanum nigrum)
Cowpeas (Vigna unguiculata):
The leaves of cowpeas are considered very healthy as they are high in fibre and low in fat. They have many bioactive compounds like vitamins and folate minerals that are vital for the prevention of damage caused by free radicals.
Folate plays a role in the preventing mutations, particularly during the DNA methylation that can cause activation of tumour genes.
The vitamin, ascorbic acid present in this vegetable also exhibits important functions. This vitamin protects the DNA and cell membrane from damage caused by free radical.
Cowpeas also contains high levels of anthocyanins and phenolic content. Anthocyanins are flavonoids, which are suggested to show antioxidants activities and a few anticancer effects.
Spider Flower (Cleome hassleriana):
These flowers are used in different parts of the world to cure various health conditions such as cough, headache, and neuralgia. Their leaf paste is used to treat rheumatism, and its juice therapy is used against the ear disease. This vegetable is also used for the formation of a concoction in Kenya, which is utilized to cure scurvy.
This plant is rich in amino acids such as glutamic acid and histidine and vitamins like vitamin C. Due to these nutrients, this plant exhibits potent antioxidant properties and aids in scavenging free radicals and toxins. This property of this plant can potentially aids in preventing certain cancer cell lines.
Black nightshade (Solanum nigrum):
Solanum nigrum (black nightshade) is a medicinal plant that belongs to the family of Solanaceae. Certain studies reveal that three steroidal glycosides β2 solamargine, degalactotigonin and solamargine obtained from this plant show cytotoxicity on tumour cell.
This plant is used in various cultures for the cure of inflammation and other conditions. It is indicated to contain many active compounds such as polyphenols and glycoprotein that are affective in immune modulation. Immune modulation is the alteration of an immune response. The black nightshade extracts are shown to enhance the immunity by rising the CD-4 cells and T-cells that are important against tumour formation.
It is evident that these African leafy vegetables show notable effects in the inhibition of cancer cell growth. They exhibit chemo-preventive activities against cancer progression. Therefore, including these African leafy vegetables in the diet would be very beneficial for healthy and salubrious life.