What are phytochemicals?
Phytochemicals are natural chemicals that plants make which serve many different functions for the plants healthy life. They can help keep plants from getting diseases from invading bacteria’s or fungi, and they can repel pests. They supply a plant its colour eg lycopene in red tomatoes, its aroma like allicin in garlic, or its taste like menthol in mint leaves.
As well as these pleasant attributes, eating a higher intake of phytochemical rich foods such as colourful fruits, vegetables, herbs, pulses, spices and teas is associated with a lower risk of cancer and relapse after treatments (WCRF World Cancer Research Fund). The international evidence for their anti-cancer mechanisms of action and other clinical benefits is well documented. Wellbeing programmes highlight the importance of phytochemical rich diets, along with other lifestyle factors with guidelines from influential organisations such as American Society of Clinical Oncology [ASCO].By concentrating these foods or extracted elements of these foods into nutritional supplements gives an opportunity to boost their beneficial anti-cancer effects.
Potential anti-cancer mechanisms of phytochemicals?
1. Antioxidant properties. The most quoted cancer prevention mechanism is via their antioxidant activity. A number of clinical studies involving known common carcinogens have highlighted the antioxidant properties of phytochemicals.
2. Reducing chronic inflammation. Another key anti-cancer mechanism of phytochemicals appears to be their ability to reduce inappropriate inflammation. It is now well established that inflammation is intimately involved in the cancer process, particularly in the promotion and progression stages of cancer. Inflammation is closely associated with oxidative stress.
3. Direct biological effects. More recently, it has been discovered that phytochemicals have an affect on several cancer process through modulation of cellular and signalling events involved in growth, invasion and metastasis.
4. Phytochemical (Hormonal effects) Some polyphenols and other phytochemicals are also able to influence cancer via a hormonal mechanism.
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