Benifits of Fruits and Vegetables
Their contribution as a group is estimated at 91% of vitamin C, 48% of vitamin A, 27% of vitamin B6 , 17% of thiamine, and 15% of niacin in the diet.
Fruits and vegetables also supply 16% of magnesium, 19% of iron, and 9% of the calories. Legume vegetables, potatoes, and tree nuts (such as almond, filbert, pecan, pistachio, and walnut) contribute about 5% of the per capita availability of proteins in the diet,
and their proteins are of high quality as to their content of essential amino acids.
Nuts are a good source of essential fatty acids, fiber, vitamin E, and minerals. Other important nutrients supplied by fruits and vegetables include folacin, riboflavin, zinc, calcium, potassium, and phosphorus.
Fruits, nuts, and vegetables in the daily diet have been strongly associated with reduced risk for some forms of cancer, heart disease, stroke, and other chronic diseases.
Some components of fruits and vegetables are strong antioxidants and function to modify the metabolic activation and detoxification/disposition of carcinogens, or even influence processes that alter the course of the tumor cell (Wargovich, 2000).
Although antioxidant capacity varies greatly among fruits and vegetables (Prior and Cao, 2000) it is better to consume a variety of commodities rather than limiting consumption to a few with the highest antioxidant capacity.
The USDA 2000 Dietary Guidelines (USDA, 2000) encourage consumers to:
(1) enjoy five a day, i.e., eat at least 2 servings of fruits and at least 3 servings of vegetables each day.
(2) choose fresh, frozen, dried, or canned forms of a variety of colors.
(3) choose dark-green leafy vegetables, orange fruits and vegetables, and cooked dry beans and peas often. In some countries, consumers are encouraged to eat up to 10 servings of fruits and vegetables per day.
There is increasing evidence that consumption of whole foods is better than isolated food components (such as dietary supplements and nutracenticals).
For example, increased consumption of carotenoid-rich fruits and vegetables was more effective than carotenoid supplements in increasing LDL oxidation resistance, lowering DNA damage, and inducing higher repair activity in human.
fruits and vegetables and on the bioavailability of nutrients taken as dietary supplements or as foods that contain these nutrients.
Examples of the components of fruits and vegetables that have positive effects on human health and their important sources.
|Elements||Sources||Impacted human diseases|
|Antioxidants||cancer, cataracts, heart disease, stroke|
|Vitamin C||broccoli, cabbage, cantaloupe, citrus fruits, guava, kiwifruit, leafy greens, pepper, pineapple, potato, strawberry, tomato|
| Vitamin A |
|dark-green vegetables (such as collards, spinach, and turnip greens), orange vegetables (such as carrots, pumpkin, and sweet potato), orange-flesh fruits (such as apricot, cantaloupe, mango, nectarine, orange, papaya, peach, persimmon, and pineapple), tomato|
|Vitamin E||Nuts (such as almonds, cashew nuts, filberts, macadamias, pecans, pistachios, and walnuts)|
|Fiber||most fresh fruits and vegetables, nuts, cooked dry beans and peas||diabetes, heart disease|
|Folate||dark-green leafy vegetables (such as spinach, mustard greens, and romaine lettuce), legumes (cooked dry beans and peas, green peas), oranges||birth defects, cancer, heart disease|
|Potassium||baked potato or sweet potato, banana & plantain, cooked dry beans, cooked greens, dried fruits (such as apricots and prunes), winter (orange) squash||hypertension, stroke|