Phytonutrients and vitamin and mineral supplementation have been reported to provide increased antioxidant capacity in humans. Besides vitamins and minerals, plants contain a wide variety of phytonutrients that have been reported to be involved in the prevention of chronic diseases.
Phytonutrients, also called phytochemicals, are chemicals produced by plants. Plants use phytonutrients to stay healthy. For example, some phytonutrients protect plants from insect attacks, while others protect against radiation from UV rays.
Phytonutrients can also provide significant benefits for humans who eat plant foods. Phytonutrient-rich foods include colourful fruits and vegetables, legumes, nuts, tea, whole grains and many spices. They affect human health but are not considered nutrients that are essential for life, like carbohydrates, protein, fats, vitamins and minerals.
Among the benefits of phytonutrients are antioxidant and anti-inflammatory activities. Phytonutrients may also enhance immunity and intercellular communication, repair DNA damage from exposure to toxins, detoxify carcinogens and alter estrogen metabolism.
Phytonutrients also have antioxidant and anti-inflammatory properties that can help support a healthy human body.
Phytonutrient health benefits
While their antioxidant qualities lead the pack in healthful benefits, phytonutrients are also known for other characteristics:
Carotenoids: These are beneficial for eye health and immune health. Two of the six more common carotenoids lutein and zeaxanthin are found in the retina and can decrease your risk of developing macular degeneration by 43 per cent, according to studies.
Flavonoids: These can protect against cancer and cardiovascular disease. These phytochemicals contribute to healthy cell communication. This can trigger detoxification, decrease inflammation, and reduce the risk of tumours spreading.
Glucosinolates: These are similar in helping to prevent cancer. Found predominantly in cruciferous vegetables such as broccoli, bok choy, cauliflower and brusse sprouts they help to eliminate toxins in the body.
Types of phytonutrients
There are classes of phytonutrients, determined by chemical structure. Phytonutrient classes include: Betalains; Chlorophyll; Indoles; Organosulfides; Phenols; Terpenes; Triterpenes.
Within these classes are dozens of phytonutrient groups, which in turn contain hundreds of phytonutrients.
Phytonutrient groups
These include: Carotenoids; Curcuminoids; Flavonoids; Glucosinolates; Hydroxycinnamic acids; Lignans; Lipids; Stilbenes; Sulfides; Tocopherol.
Antioxidants and free radicals
Antioxidants are found in certain foods and may prevent some of the damage caused by free radicals by neutralising them. These include the nutrient antioxidants, vitamins A, C and E, and the minerals copper, zinc and selenium.
Other dietary food compounds, such as the phytochemicals in plants, are believed to have greater antioxidant effects than vitamins or minerals. These are called the non-nutrient antioxidants and include phytochemicals, (such as lycopenes in tomatoes and anthocyanins found in cranberries).
The effect of free radicals
Some conditions caused by free radicals include:
Deterioration of the eye lens, which contributes to vision loss.
Inflammation of the joints (arthritis).
Damage to nerve cells in the brain, which contributes to conditions (such as Parkinsons or Alzheimers disease).
Acceleration of the ageing process.
Increased risk of coronary heart disease, since free radicals encourage low-density lipoprotein (LDL) cholesterol to stick to artery walls.
Certain cancers triggered by damaged cell DNA.
Disease-fighting antioxidants
A diet high in antioxidants may reduce the risk of many diseases (including heart disease and certain cancers). Antioxidants scavenge free radicals from the body cells and prevent or reduce the damage caused by oxidation.
The protective effect of antioxidants continues to be studied around the world. For instance, men who eat plenty of the antioxidant lycopene (found in tomatoes) may be less likely than other men to develop prostate cancer.
Lutein, found in spinach and corn, has been linked to a lower incidence of eye lens degeneration and associated vision loss in the elderly.
Flavonoids, (such as the tea catechins found in green tea) are believed to contribute to the low rates of heart disease in Japan.
Vitamin supplements and antioxidants
There is increasing evidence that antioxidants are more effective when obtained from whole foods, rather than isolated from a food and presented in tablet form.
Research shows that some vitamin supplements can increase our cancer risk. For example, vitamin A (beta-carotene) has been associated with a reduced risk of certain cancers, but an increase in others such as lung cancer in smokers (if vitamin A is purified from foodstuffs).
A study examining the effects of vitamin E found that it did not offer the same benefits when taken as a supplement.
Also, antioxidant minerals or vitamins can act as pro-oxidants or damaging oxidants if they are consumed at levels significantly above the recommended amounts for dietary intake.
A well-balanced diet, which includes consuming antioxidants from whole foods, is best. If you need to take a supplement, seek advice from your doctor or dietitian and choose supplements that contain all nutrients at the recommended levels.
The Role of Minerals in Health:
Every living cell on earth depends on minerals for proper structure and function. Minerals are naturally occurring chemical elements that are found in the earth. Erosion breaks down stone, rocks, particulate and sand to form soil, which is the basis for plant growth. The minerals are thereby passed on to the plants, which are in turn passed on to the herbivorous animals that eat the plants. Humans eat plants and the herbivorous animals to obtain necessary mineral nutrients.
Minerals are needed for the proper composition of body fluids, including blood, and for the proper composition of tissues, bone, teeth, muscles and nerves. Minerals also play a significant role in maintaining healthy nerve function, the regulation of muscle tone, and supporting a healthy cardiovascular system.
Like vitamins, minerals also function as coenzymes that allow the body to perform its biochemical functions including: energy production; growth; healing; and proper utilisation of vitamins and other nutrients.
The human body must have a proper chemical balance that depends on the levels of different minerals in the body and in the ratios of certain mineral levels to one another. If one mineral level is out of balance, all other mineral levels may be affected. If this type of imbalance is not corrected, a chain reaction of imbalances can begin that may lead to disease or illness.
Minerals are nutrients that are essential for the body. There are 22 of them in total.
Types of minerals
Minerals can be broken down into two types: macro-minerals and micro-minerals. They are also sometimes referred to as major minerals and minor (or trace) minerals.
Macro-minerals (Major minerals)
The macro-minerals include: Calcium; Phosphorus; Magnesium; Sodium; Chloride; Potassium; and Sulfur.
Macro-minerals, in particular calcium and phosphorus, tend to play structural roles within the body.
The body needs over 100mg per day of each macro-mineral. This may sound like a large amount, but it can be put in perspective by considering that a dollar bill weighs 1000mg.
Micro-minerals (Trace minerals)
There are more than 12 micro-minerals. The main ones are: Iron; Copper; Zinc; Manganese; Iodine; Selenium.
Micro-minerals are not needed in as high amounts as micro-minerals, as they are generally used as catalysts in enzyme reactions.
More specifically, the body needs less than 100mg per day of each micro-mineral.
(The author is jr scientific officer, Drugs Testing Laboratory, Bangalore. He can be contacted at siddu.tadasad@gmail.com)