High-Fat, Low-Carbohydrate Diets - Millions of Americans have joined the low-carb craze and started high-fat, low-carb diets such as the Atkins Diet, and the Zone Diet. They are made up of about 60% fat, 10% carbohydrate, and 30% protein. These diets say you can eat high amounts of fat and protein while getting very low amounts of carbohydrates in the form of vegetables. The main premise of the low-carb diet is that a diet low in carbohydrates leads to a reduction in body’s production of insulin. The end result is that fat and protein stores will be used for energy. So you stuff yourself full of unlimited amounts of meat, cheese, and butter, and only eat a small portion of carbohydrates.

People who start the diet usually lose a great amount of weight, but it’s not permanent weight loss. Instead of burning fat, the lose water and precious muscle tissue. Furthermore, these diets are low in several nutrients and contain excess amounts of cholesterol and saturated fats, substances that increase the risk of heart disease. Plus, regardless of what they claim, the enormous amounts of protein put a strain on your kidneys.

Moderate Fat Diets - Next, there are the moderate fat diets. Moderate fat diets include diets like Weight Watchers, the USDA Food Guide Pyramid, and Jenny Craig.  These diets are made up of about 25% fat, 60% carbohydrate, and 15% protein. They encourage the intake of whole grains, fruits, vegetables, and essential fatty acids found in foods like olive oil and salmon. These diets are usually nutritionally balanced if the dieter eats a variety of foods from all categories. For example, Weight Watchers operates on a point system where foods get a number of points based on calorie, fiber, and fat content. Dieters get a specific amount of points they can use for the day. While it’s not encouraged, they may choose to spend most of their points on carbohydrates instead of balancing it out. This could lead to deficiencies in nutrients such as calcium, iron, and zinc. However, if followed properly, these diets are probably the most successful for losing weight and keeping it off.

Low and Very Low-Fat Diets - Finally, you have your low-fat and very low-fat diets. Diets in this category include the Dr. Dean Ornish’s Diet and the Pritkin Plan, among others. They are made up of about 13% fat, 70% carbohydrates, and 16% protein. These diets are mostly vegetarian diets and don’t recommend eating a lot of meat. Like the low-carb diets, you can eat unlimited amounts of certain foods. Because you can’t eat a lot of meat, these diets are deficient in zinc, vitamin B12, and essential fatty acids. Also, it is so restrictive that people find a hard time staying on it for life and end up gaining their weight back.