Plants contain phytonutrients that supply us with a multitude of nutrients essential for optimal health.
WE all know that the immune system keeps us safe from infections and attacks from harmful pathogens.
Immune cells are found in every part of the body, from the skin to the blood system, vital organs and more.
In the same way, plants also have an immune system that protects them from disease, insects, radiation, environmental pollution and harsh weather, as well as recovering from “injuries”.
The plant immune system is mainly formed from phytonutrients – natural compounds found in different parts of the plant, such as fruits, seeds, leaves or roots.
Plant foods contain, in addition to their common macronutrients and dietary fibre, a wide variety of biologically active micro-components called phytonutrients.
Different plants offer different phytonutrients and health benefits. Many plant foods even contain many phytonutrients, such as an orange, which has 170 phytonutrients.
In recent decades, experts have found that phytonutrients can also help to enhance our health and vitality.
Research also shows that phytonutrients can successfully prevent or treat chronic non-communicable diseases such as cancer, diabetes, heart problem and high blood pressure.
What are phytonutrients?
‘Phyto’ is a Greek word meaning plant, hence, phytonutrients refer to the nutrients that are derived from plant material. Apart from being high in fibre, vitamins and minerals, the phytonutrients in plants help strengthen the immune system, prevent disease and improve health.
Also known as phytochemicals, phytonutrients function to prevent cell damage, prevent cancer cell replication and decrease cholesterol levels. Studies show that plant foods have 64 times more antioxidants than animal foods, which speaks volumes about their health benefits.
Some phytonutrients are water-soluble, while others are fat-soluble. Fat-soluble phytonutrients need fat in the diet in order to be properly absorbed.
Some phytonutrient compounds are so dominant that you can still detect them for quite some time after consumption, such as “garlic breath”, strong odours after taking durian, petai or jering, and bright-red faeces from eating dragon fruit.
In order to preserve the phytonutrients, most plants are best taken raw. The only exception is tomatoes, which have been found to release more lycopene when turned into juice or sauce.
Phytonutrients contain pigments that give certain plants their colour. However, many pale-coloured plant material such as garlic, onions and leeks also contain high levels of sulphur, a potent phytonutrient.
Certain plants with deep rich colours such as broccoli are even known as superfoods for their high phytonutrient content.
In order to reap the full benefit of phytonutrients, it is best to choose a rainbow of colours on your plate. The more colourful, the higher the range of phytonutrients you will get!
Types of phytonutrients
Phytonutrients can be divided into various categories according to their natural chemical structure. Some of the more well-known phytonutrients include:
Antioxidants: Reduces inflammation and cancer risk, and improves bowel movement through larger stool size. Found in fruits and vegetables like bell peppers, cloves, peppermint, blackberries, apples, oranges, red rice, carrots, kailan and others.
Lycopene: This gives the red or pink colour to tomatoes, watermelon and carrots. Reduces risk of heart disease and prostate cancer.
Anthocyanins: Boosts short-term memory, reduces risk of Alzheimer’s disease, and stimulates fat burning. Found in fruits that are red or purple such as dark purple or red grapes, cherries, blueberries, blackberries, raspberries and strawberries.
Carotenoids: Act as antioxidants in the body to fight free radicals, the key cause of tissue damage; improves skin conditions; and protects against vision loss, heart disease and certain cancers. Found in fruits and vegetables that are yellow, orange and red, such as tomatoes, papaya, guava, pink grapefruit, watermelon, chillies, pumpkin and others.
Lutein and zeaxanthin: Protects against cataracts, glaucoma and macular degeneration – major causes of blindness. Found in spinach, leek, kailan and others.
Sulforaphane: Stimulates the body’s natural enzymes to detoxify carcinogens before they damage cells; protects against cancer by reducing oxidative stress; and improve cancer survival rates. Available in cruciferous or the cabbage family of vegetables like broccoli, cauliflower, asparagus, brussels sprouts and bak choy.
Phytoestrogens: Structurally similar to hormones and can interrupt cancer development by mimicking hormone function in the body, as well as reducing risk of endometrial cancer and bone loss. Found in soy, kudzu, red clover, sesame seed, flax and rye.
Phytosterols and saponins: Structurally similar to cholesterol and can help lower blood cholesterol by decreasing cholesterol absorption from the digestive tract. Saponins are found in fenugreek, quinoa, alfafa and chick peas, whereas phytosterols are present in plant oils, nuts and seeds, cereals, legumes, kidney beans, grapefruit, strawberries and asparagus.
Allylic sulphide: Contains sulphur and can help stimulate the activity of enzymes that detoxify carcinogens from environmental toxins, reduce cancer risk, prevent colds, improve blood circulation, reduce inflammatory conditions, and improve high blood pressue, diabetes, physical exhaustion, fatigue and insomnia. Found in garlic, shallots, onions, leeks and chives.
Other phytonutrient-rich foods include herbs and spices that serve to control blood sugar, raise good cholesterol levels and improve digestion.
Tips to get started
If you are contemplating starting on more greens and fruits, here are some things to guide you along:
1. Increase intake slowly. Taking a lot of fruits and vegetables suddenly may shock your body system into “denial”, causing problems such as gassiness and bloatedness.
2. Eat foods with at least seven different colours every day to enjoy a wide variety of nutrients. The brighter the colours, the better!
3. Choose from a wide spectrum encompassing fruits, vegetables, beans, tubers, bulbs, herbs, seeds, legumes, nuts and wholegrains.
4. Taking multivitamin and mineral supplements will not replace the nutrients found in fresh food. A healthy diet is still the key to good health.
5. Be creative in incorporating more varieties of phytonutrients into your diet. Examples include making a fruit and vegetable smoothie, rainbow-coloured salad, mixing fruits into oats and yoghurt, or even whipping up a vegetable curry.
6. Snack on fresh or dried fruits and nuts instead of cookies, cakes or processed foods.
Phytonutrients may not be essential for keeping you alive, unlike the vitamins and minerals in plant foods.
But the disease-preventing, and even disease-reversing, properties of phytonutrients will keep your body working better, for a longer time.
Datuk Dr Nor Ashikin Mokhtar is a consultant obstetrician & gynaecologist (FRCOG, UK). For further information, visit www.primanora.com. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
The views expressed are entirely the writer's own.