2 Eat sugar-free food and you won't gain weight.

So-called sugar-free food only means the food doesn't contain sucrose. A lot of drinks have sugar, and studies have indicated drinks containing sugar will increase chronic disease risk. Biscuits, bread and desserts also contain sugar to some extent. Some institutes suggest that for the majority of people, sugar in food should be less than 10 percent, with 5 percent being ideal.

Also: In lots of sugar-free food, the percentage of fat is often high, and fat provides twice the calories as sugar does in same amount of weight.

3 Lemonade helps prevent cancer.

It is true that lemons have diversified nutrients, including vitamins and minerals, but if we think about the quantity of Vitamin C, the same amount of green pepper has three times of Vitamin C content of lemon.

The World Cancer Research Fund and the United States National Cancer Institute have proved with evidence that eating fruits and vegetables can reduce the risk of cancer, but what they mean is fruits and vegetables as a whole, not just one kind of fruit, and you certainly cannot prevent cancer through drinking fruit-flavored water.

Lemonade can increase intake of Vitamin C, but diet influences the incidence of cancer through a combination of factors.