By The Times of India, October 12, 2011
The humble guava is the healthiest fruit for the human body, while the pineapple is at the bottom of this index. The first-of-its-kind research to evaluate the amount of natural antioxidant levels of 14 fresh fruits commonly consumed in India has come up with surprising revelations. Guava came in at the top, followed by the Indian plum. Mango, pomegranate, custard apple and apple are among the other fruits that offer the highest amount of antioxidants.
The study - conducted by Hyderabad's National Institute of Nutrition - found that pineapple, banana, papaya, water melon and grapes had the least amount of antioxidants. Antioxidants play a crucial role in preventing cellular damage - the common reason for aging, cancer and several degenerative diseases.
In a study published in the journal "Food Research International", lead author Dr D Sreeramulu from NIN's endocrinology and metabolism division found that the antioxidant activity ranged from as high as 496 mg/100 grams in guava to as low as 22 mg/100g in pineapple.
Sreeramulu told TOI, "The findings came as an eye-opener. We usually believe expensive fruits are the richest source of nutrition. But our extensive research shows that fruits that are rich in antioxidants help scavenge free radicals that destroy tissues." Modern lifestyles, he adds, lead to an excess of free radicals.
Fruit-rich diet cuts cell damage risk
A fruit-rich diet is linked to lower risk of chronic degenerative diseases, besides the added incentive of slowing aging. Adding to worldwide studies that show fruits are rich sources of phenolic compounds and antioxidant activity (AOA), Dr Sreeramulu of the National Institute of Nutrition in Hyderabad says even the commonly available guava can enrich the Indian diet.
Sreeramulu's study to determine the AOA and phenolic content of fresh fruits commonly consumed in India has provided an index of the healthiest fruits. The guava and Indian plum have pipped the pineapple in terms of antioxidant value.
"Dietary polyphenol intakes from fruits and vegetables are known to reduce the risk of coronary heart disease and cancer. The present data will be useful to consumers to plan antioxidant rich diets and to the health professionals and nutritionists in estimating the daily intakes of phenolic antioxidants and their impact," he added.
"Current lifestyles cause over-production of free radicals. Free radicals are atoms that can start a chain reaction and cause damage when they react with important cellular components such as DNA or cell membrane. Cells may function poorly or die if this occurs," says Sreeramulu.
"Natural antioxidants protect from oxidative stress and associated diseases, and therefore, play an important role in healthcare. Fruits are important dietary sources of antioxidant polyphenols to humans. In recent times, natural antioxidants have attracted considerable interest among nutritionists, food manufacturers and consumers because of their presumed safety and potential therapeutic value."
Three samples of each variety of fresh fruit were purchased and edible portions were cut into small pieces and extracted with acidified aqueous methanol.