Phytochemicals are nonnutritive natural plant chemicals found in fruits, vegetables, legumes and nuts. They have a positive impact on the health as they contain protective disease preventing compounds. Some of the most common phytochemicals are-
- Carotenoids- beta carotene, lutein, lycopene, zeaxanthin
- Flavonoids- wuercetin, anthocyanins, hesperidin
- Ellagic acid
The phytochemicals from fruits and vegetables play a key role in reducing chronic disease risk. Apples are rich source of phytochemicals and have been found to reduce the risk of cancers, asthma, diabetes and cardiovascular diseases. Storage usually does not affect the phytochemicals of apples, but processing does.
Phytochemicals attribute much of the protective effects of fruits and vegetables. We have been able to identify thousands of phytochemicals, but still, there are many which are yet to be identified. Phytochemicals
- Inhibit cancer cell proliferation
- Regulate inflammation
- Protect against lipid oxidation
Various metabolic activities in our body result in production of oxidants. Our bodies have a complex antioxidant defense system. Still, some damage is always caused by oxidants. Oxidatives stress our body that can cause damage to larger biomolecules such as proteins, lipids and DNA. Approximately, there are 10,000 oxidative hits to DNA per cell each day in human bodies. As most of the fruits and vegetables are high in antioxidants, eating diets that are rich in such foods help relieve this oxidative stress. This can prevent many chronic diseases and also delay aging.
Many phytochemicals are under clinical trials for their potent medicinal properties. Lycopene which is found in tomatoes is being tested to cure cardiovascular diseases and prostate cancer as it helps in improving blood flow through heart.
Spinach is rich in zeaxanthin and lutein that improve the human vision. Carrots are good source beta carotene. Foods that have highest anticancer activity are-
It is also interesting to note that most of phytochemicals are not destroyed by cooking as most of these compounds are heat stable. Vitamin C is partially lost during the process of cooking but carotenoids and indoles actually increase during cooking. These are found in broccoli.
Soybeans have high levels of various compounds that have anti-cancer properties. They also decrease the cholesterol level in the body.
Citrus fruits are rich source of vitamin C, potassium, folic acid and pectin. They are also rich source of active phytochemicals that protect our health in long run. There are almost 170 phytochemicals in orange. They have various properties such as anti-inflammatory, anti-tumor activity, inhibition of blood clots and quite strong antioxidant activity.
Whole grains are also rich in few phytochemicals that reduce the risk of cardiovascular disease and cancer. But it is important to consume them as whole. Refining process causes 200-300-fold loss in the phtyochemical content.
Flax seed flour is usually used in bread and few bakery products. It enhances the flavor and also nutritional and health benefits. It lowers the blood cholesterol. Flax seed oil is known to be the richest source of omega-3 fatty acids and helps prevent arthritis, lupus and various allergies. It also boosts the immune system.
Pigmentation of food makes it more appealing to consume. There are around 2000 plant pigments in our foods. They not only appeal to our senses, but also play a major role in protecting our bodies from various diseases.
Anthocyannins is a reddish pigment found in cherries, blueberries, raspberries, strawberries etc. inhibit cholesterol and provide protection against heart disease.
Various herbs such as rosemary, sage, oregano, thyme etc, are known to have strong antioxidative properties. Garlic and onion decrease the tendency of blood clots and decrease the risk of cancer.
Everyday, research is uncovering more and more disease preventing phytochemicals from plants. With the help of science, the remarkable benefits are being uncovered and are now being called as essential nutrients. As science adds knowledge about these disease preventing components, they are increasingly becoming an integral part of our regular diets as we are now more aware of their amazing properties.
More and more phytochemicals are being identified everyday. A single serving of vegetable may contain as many as 100 different types of phytochemicals. Researchers have long known that phytochemicals provide protection in plants but it is a recent discovery that they provide innumerable benefits and strong protection against human diseases as well. But if taken in high doses, some of the phytochemicals can have detrimental effects. Optimal levels of phytochemicals have not been determined so far. It varies as per genders, body types, age group and so forth.