Risks of Optifast

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Watching half an hour of television will make it clear that there are hundreds of different diets and weight loss programs on the market. Some of them have been proved to be effective, while others have not. One of the most popular weight loss programs is the Optifast diet, a liquid diet that involves only shakes, drinks and other meal-replacement beverages. According to the Optifast website, the Optifast diet is a convenient way to lose weight because it frees people from having to worry about meal planning and cooking. Even though the Optifast diet can save time and possibly lead to weight loss, there are also risks associated with doing the Optifast diet.


According to Vanderbilt University, one of the most common risks associated with liquid diets like the Optifast diet is constipation. This occurs often because the diet lacks fiber, which adds bulk to stool weight can promotes regular bowel movement. The Optifast diet also lacks fruits, vegetables, whole grains, and other types of roughage. It can be difficult for the body to form and pass stools without solid foods.


The Optifast diet provides several drinks per day and no meals with solid food. According to the diet review website Diet.com, the Optifast diet provides on average, 800 calories or fewer per day. Therefore, the Optifast diet is considered a very low calorie diet. Vanderbilt University states that very low calorie liquid diets tend to cause dizziness and a light-headed feeling, due to the fact that they do not contain enough calories.

Muscle Cramps

Another risk of using the Optifast diet is getting muscle cramps. Vanderbilt University states that the high amount of protein in liquid diets such as Optifast can lead to an electrolyte imbalance in the body. Electrolyte imbalances, and lack of enough minerals such as potassium, calcium and magnesium can lead to frequent and painful muscle cramping.


Gallstones are another risk that can occur from doing the Optifast diet. Gallstones are hard masses that can form in the gallbladder. Some people have gallstones without experiencing any symptoms, while others have a lot of pain from them. Gallstone treatment may even require surgery if they are severe enough. According to Diet.com, the risk of gallstones comes from the fact that the Optifast is very low in calories. Low calorie diets and rapid weight loss can cause the formation of gallstones, especially in women, though they can also occur in men. In fact, Vanderbilt University states that about 25 percent of those who go on liquid diets develop gallstones.

Weight Gain

Using Optifast does not teach you better eating habits, so when you stop Optifast and begin a regular diet, you run the risk of gaining back the weight you lost. You can help prevent this by improving your dietary habits while taking Optifast, and when you stop using the product you will have taken steps toward healthy changes that can help you keep the weight off.

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