40 grams is the MAXIMUM amount recommended for non-diabetic people and no added sugar, such as granulated sugar, is necessary, since it adds no nutrition to the body. If you're diabetic or borderline diabetic, please see the note at the bottom. 40 grams of sugar refers mainly to added sugar, which is anything that is put into foods rather that which is naturally occurring such as in fruit. By this logic, for instance, ALL sugar in soda would be considered "added," since the beverage itself is constructed rather than harvested.

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Actually, this is a bit of a complicated question. Carbohydrates can take the form of sugar once digested, and a certain amount of sugar, as the answer above indicates, occurs naturally in food. However, the following bit from healthatoz.com, I found helpful:

In petitioning for labeling changes regarding sugar, CSPI (Center for Science in the Public Interest), joined by dozens of leading health experts, also wants the FDA to set a maximum recommended daily intake (Daily Value) for added sugars of 10 teaspoons (40 grams) and require labels to disclose the percentage of the Daily Value a food provides.

There are many naturally occurring sugars such as sucrose which is a combination of glucose and fructose (or fruit sugar), lactose (from milk), maltose and galactose. You don't want too many of the simple sugar glucose, but you can have a few more of the complex ones. If you digest too many simple sugars, your body gets swamped and the excess that is not used by your body gets stored as fat. Also useful to know is that sugars also enters your cells using the same pathway as Vitamin C - so, too much sugar and your body does not absorb Vitamin C as well. Too much sugar also interrupts your immune system. However, you can eat or drink natural sugars in moderation - say up to 100 grams a day (like orange juice which contains quite a lot of fructose).

From a health standpoint, specifically adding simple table sugar is a favorable alternative to adding a potentially hazardous substance such as high fructose corn syrup. This isn't to say sugar itself lacks dietary benefits. Sugar, in its original state, is a naturally produced substance rich in vitamins and minerals. And if refined properly, retains these qualities (so long as it remains in the form of table sugar.) In addition, a regular intake of table sugar is important in regulating insulin productivity. There are also positive metabolic effects. Sugar is added to FDA-approved energy products for a reason--it's a safe stimulant that augments energy in a confined period of time and promotes a heart-healthy agenda. Thus, it is somewhat difficult to say exactly how much sugar per day any one person may require. For someone with a regular metabolism, that doesn't devote time to exercise, a 100g maximum should not be crossed (and in many cases not be approached.) However, athletes may consume 150% of this without seeing notable side-effects. It is important that I reiterate that in either case this threshold should not be approached. Sugar in very high doses is dangerous; if you're concerned for your health it is best to stay at a far more shallow intake than the maximum dosage recommends.

Recommended amount of any food per day is always subjective to the following:

a. Age

b. Health conditions

c. Physical activity (calorie expenditure per day)

d. General food habits (based on locality of individual, he may be consuming more of one food and may be immune to bad effects of it)

e. Others

There are many other minor factors which may determine the amount of sugars that a person needs. So based on the law of individualism, each individual is unique and their needs are different based on various factors.

Processed sugar is not necessary at all in anyone's daily diet. It should be avoided. Our body gets enough carbohydrates from ordinary foods and converts raw carbs to sugars as needed. Grains, fruits, and other carbs provide enough(sometimes too much) sugars as is. Dried fruits such as raisins are especially full of sugars. To add even more processed sugar is harmful. As a dentist, I see daily the harm done by hard candy, chocolate, soda, cough drops (98% sugar), sweetened tea, coffee (with either sugar and sometimes powdered cream substitute (contains high % sugar), pastries, pies, cakes, cookies. None of these foods are necessary and should be avoided unless it is a rare special occasion. Hope I have been of some help to you. Consult a dietitian if you disagree with anything that I have said.

**NOTE FOR DIABETICS

The answer is different for each individual. A much more useful answer that may save lives is: Everyone is different. If you are diabetic and worried about harming your body with sugar intake (as you should be), then it is small comfort if your intake is fine for average people but tends to cause high blood sugar for youin particular.

Rather than researching grams of sugar and asking people (or even doctors) if that's harmful, you should buy a glucometer (blood glucose meter) at any drugstore, learn to use it, and find out what foods you can eat (on your current medicine and diet) that will keep your blood sugar in the safe ranges according to the link below "How to keep your blood sugar under control".

Fasting blood sugar under 100 mg/dl (5.5 mmol/L)

One hour after meals under 140 mg/dl (7.8 mmol/L)

Two hours after meals under 120 mg/dl (6.6 mmol/L)

After you have determined how much milk or sugar or carbohydrate you can eat and stay within these boundaries, then and only then are absolute grams of carbohydrate or sugar a useful thing to know.