False.
Over the past ten to fifteen years there has been a sharp increase in the number of high protein, low carbohydrate diets being marketed. I believe one of the reasons so many people explore these types of diets is the mistaken belief that carbohydrates make you fat. Carbohydrates are a macronutrient; macronutrients are nutrients we need in larger quantities to help provide energy to cells for normal growth and development. Protein and fats are also macronutrients. Carbohydrates are a very important energy source for our bodies. In fact, many medical and exercise science researchers believe that carbohydrates are the preferred energy source for the brain, and also are important for supplying the energy needs of muscles and other organs in the body. Various organizations recommend that you consume somewhere between 45 and 65% of your daily calories from carbohydrates. So, roughly speaking, it is recommended that the average person consumer more than half of their daily calories in carbohydrates. If your daily caloric intake is about 2,000 calories that would mean you would want to consume roughly 250 grams of carbohydrates per day. One study published in the journal Obesity Research (1996) showed that subjects who ate a carbohydrate rich, low fat diet lost more weight and fat mass than controls that did not change their diets. I find it hard to believe that nutritional experts would recommend we consumer over half our calories in carbohydrates, if carbohydrates in fact made us fat. Additionally, it is often recommended that we consume more complex carbohydrates (whole grain pasta, vegetables) instead of simple carbohydrates (sugars). Now eating too many carbohydrates certainly does have the potential to add extra pounds to your body, just like eating too many fats or proteins. It really comes down to the total number of calories you consume.
Reference:
Siggaard R, Raben A, Astrup A: Weight loss during 12 week’s ad libitum carbohydrate-rich diet in overweight and normal-weight subjects at a Danish work site. Obesity Research (1996), Vol 4, pps. 347-356.