There are MANY many studies out there that prove that high sugar and high glycemic index foods should be minimized or avoided. But there are also a growing number of studies that prove low carbers lose more weight.

In the old days, people felt you needed massive amounts of carbohydrates to stay healthy. People even erroneously thought that your brain needed carbohydrates! Now with new studies and improvements in biology, we understand how the body works far better. For example, it is GLUCOSE the brain needs - and this is provided by proteins and low carb foods just as well as by that chocolate donut.

Breakfast - Carbs make People Hungry
A study done at the Boston Children's Hospital found that teenagers who ate low carb breakfasts were far less hungry at lunchtime even with the exact same # of calories.
Boston Low Carb Breakfast Study

Breakfast Round 2 - Carbs make Children More Hungry
Yup, the study done at the Oxford Brookes University found that kids 8-12 who ate low carb breakfasts again were far less hungry at lunchtime than kids who ate the EXACT same number of calories in a high carb manner.
British Low Carb Breakfast Study

Low Carbers Lose More Weight
A strict study done by the Harvard School of Public Health has proven what low carbers have known for years - that on a low carb diet you can eat more calories and still lose weight.
Harvard Diet Study

Nutritionists Push for Glycemic Index Labels
This is a way to sum up hundreds of studies that prove that high glycemic index foods are unhealthy. Foods that have high glycemic indexes (say white bread and white rice) tend to spike your blood sugar levels. Then when your blood sugar levels drop after you finish eating, your body thinks it is in a sugar deficit situation and craves more food. It creates mood swings, cravings, binge eating and much more. Just about every diet out there nowadays warns you to stay away from high glycemic index foods - and low carb was at the forefront of this move.
Nutritionists and Glycemic Index