|编译服务：||食物与营养||编译者：||潘淑春||编译时间：||Apr 29, 2016||浏 览 量：||2|
Getting your daily nutrients can be more difficult now than it was in the past. Fruit and vegetables grown decades ago were much richer in vitamins and minerals than the varieties most of us get today. A study of British nutrient data from 1930 to 1980, published by the British Food Journal, found that in 20 vegetables the average calcium content had declined by 19 percent, iron by 22 percent and potassium by 14 percent. Another study concluded that we would have to eat eight oranges today to derive the same amount of Vitamin A that our grandparents would have gotten from one.
The reasons for this include:
Industrial farming, processing and trading methods are causing a decline of minerals e.g. copper, iron, magnesium and potassium, in fruit and vegetables..
Modern-day intensive agricultural methods are stripping more and more nutrients from the soil in which we grow food..
Artificial fertilizers used to speed the growth and productivity of crops might not take account of the delicate balance of mineral requirements in plants and foods..
Fruit and vegetable often embark on a long journey before landing in our homes. Nutritionists say this may be affecting their vitamin content as fresh fruit and vegetables are more likely to contain the most vitamins..
Using artificial ripening on vegetables like tomatoes lowers the nutritional value of the products - tomatoes accumulate nearly all the sugars and many flavonoids in their last 3 days on the vine..
To ensure you get the most nutritious fruits and vegetables, you should buy regularly from local organic farms.