People think that sugar tastes good, so it must be harmless.
People have no idea that sugar and starchy foods could be the culprit behind the obesity wave. People don’t understand the biochemistry that leads from sugar and starchy food intake to the deposit of fat in fatty tissue.
People don’t understand that there is an insulin response anytime you eat too much sugar and that after years and years of abuse of your pancreas there comes a point where you do not produce enough insulin anymore. This is the point when you get diabetes. Diabetes has a host of possible complications. Blood Glucose Control Studies for Type 1 Diabetes: DCCT and EDIC | NIDDK.
Many people do not know that in response to a sugary meal the body first stores excess sugar as glycogen in the liver and muscle tissue. When the glycogen stores are full, the excess sugar is metabolized by the liver.
This is the point when the liver produces too much LDL cholesterol (the bad cholesterol) and triglycerides. These are stored as fat in fatty tissue, but also in blood vessels.
You can simplify this and say: too much ends up in fatty tissue and makes a person obese.
The process does not stop here: the lining of the arteries are filled with atheromatous deposits, so the coronary arteries and the brain vessels are narrowing. Eventually this process leads to heart attacks and strokes. Kidneys and legs are also affected. These problems often lead to a premature death.
The American Heart Association (AHA) clearly spelled out what the limits are: Added Sugars:
For men: a daily dose of 9 teaspoons of sugar from all foods, for women a daily dose of 6 teaspoons of sugar from all foods.