Custom Search

Phytonutrients in the diet

Apart from the major food principles like protein, carbohydrates, and fats, large number of food items we consume consists of invaluable components in them known as phytonutrients, or plant derived chemical substances. Although their caloric value is insignificant, inclusion in our diet in adequate levels of these inert compounds is imperative since the potential benefits in terms of their direct contribution to health promotion and disease prevention are really enormous.

orange peel mango peel with fruit peeler
Orange peel.
Photo courtesy: fdecomite
Mango peel with fruit peeler.
Photo courtesy: ms.Tea 

Changes in lifestyle and dietary patterns have resulted in modern world illnesses like coronary artery disease, diabetes, stroke, cancers, etc., in higher frequencies than ever before. Several research and experimental epidemiological studies have clearly suggested that the trends in these diseases patterns link very closely to the diet we consume.

Consequently, new interest has risen in the medicinal properties of food items like herbs, spices, vegetables, and fruits along with their peels.

Health benefits of phyto-nutrients

Studies have found that certain chemicals other than nutritional principles in them have anti-mutagenic, free-radical scavenging, and immunity boosting functions, which help promote health and prevent diseases, apart from their nutritive value.

Phytonutrients are present abundantly in the plant world. Examples include:

1. Anti-oxidants,

2. Phyto-sterols (plant sterols),

3. Non-digestible (non-starch) carbohydrates such as tannins, pectin, cellulose, hemi-cellulose, mucilage, etc.,

4. Natural acids,

5. Enzymes and lecithin.


Studies suggest that cancers occur due to a series of mutational events occurring at the cellular level triggered by free-oxygen radicals and reactive oxygen species (ROS). These free radicals have the ability to damage cell’s DNA, cell membrane and proteins like ion channels, receptors, etc. Antioxidants, by virtue of their reduction potentials, can bind to oxidation radicals at these levels and interrupt free-radical injury by reversing or limiting the extent of damage. Several groups of antioxidants have been identified such as poly-phenolic flavonoids, anthocyanins, etc. Examples of certain anti-oxidants in fruits and vegetables include:

Plant sterols

Plant sterols, also known as phyto-sterols, constitute mainly beta-sitosterol; however, they differ in function than human sterols like cholesterol. They are poorly absorbed by humans and in the process, appear to block the absorption of dietary cholesterol as well; and thus help reduce blood LDL-cholesterol levels.

Initial research studies have been found that experimental doses of plant sterols can be effective in countering the effects of testosterone-mediated hypertrophy in prostate glands. Again, they help minimize the risk of BPH and prostate cancer in men. Their effects in women, however, are found to be neutral or some beneficial effect on breast, uterine and ovarian receptors.

Non-digestible carbohydrates, natural acids and enzymes

The other phytochemicals include detoxifying agents like indoles, isothiocyanates, non- starch polysaccharides (NSP) or dietary-fiber like gums, hemicellulose, mucilage, pectin, tannins, and alkaloids like caffeine and non-protein amino acids. NSP, also commonly known as dietary fiber, increase bulk to the food and helps prevent constipation by decreasing gastro-intestinal transit time. They also bind toxins in the food, prevent their absorption, and help protect the colon mucus membrane from cancers. In addition, dietary fibers bind to bile salts (produced from cholesterol) and decrease their re-absorption, thus help lower serum LDL-cholesterol levels in the blood.

In conclusion, phytonutrients provide crucial links between health and nutrition. A well-balanced food that is rich in phytonutrients such as fresh fruits, herbs and vegetables can help minimize free radical and reactive oxygen species (ROS) mediated diseases.

Please read further interesting phytonutrients articles...
  • Read about fruit peel nutrition facts and health benefits.

  • Read about one of the most important natural anti-oxidant Beta-carotene.

  • Nutrition facts and health benefits of coconut water.

<<-Back to Home page from Phytonutrients.

Visit here for very informative pages on:-

Further Resources:

1. Dietary, Functional, and Total fiber- National agricultural library, USDA-pdf 

2. Stanford School of Medicine Cancer information Page-Nutrition to Reduce Cancer Risk (Link opens in new window).

3. Antioxidants and Cancer prevention- National Cancer Institute.