How many grams of sugar is too much?

If you cut out all the obvious sources of sugar—candy, sweet desserts, soda, fruit juice, and processed foods with added sugar—you'll be way ahead of the game. Then you need to look at more complex carbohydrates, like grain flours and starches, and starchy vegetables like potatoes, since these all turn into sugar very quickly upon digestion. Ideally, you should cut all these foods to nearly zero to keep you daily sugar load (added and natural sugars plus starches) to something like 50 to 80 grams per day. For more detailed information, this is a good place to start:

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