Very Low Calorie Diets

Originally liquid fasting diets, Very Low Calorie Diets, first made their appearance in the 1970’s, and experienced a resurgence in the 1980’s when millions of television viewers saw Oprah Winfrey squeeze into the size 8 jeans she had long since ‘grown’ out of. But these diets fell out of favor with physicians and nutritional experts due to nutrition shortfalls.

The Centers for Disease control report that 67% of adults age 20 and over are overweight or obese. That means that almost 7 out of 10 adults are at a greater risk of life-threatening conditions such as heart disease, hypertension, some cancers, and diabetes. Those seven adults also have a tendency to experience joint and muscle pain, increased social phobias, and can find simple tasks such as fitting into a movie theatre seat to tying their shoes more challenging than their average weight counterparts.

For adults, weight and height measurements are used to calculate a number called the “body mass index” (BMI). BMI is used because, for most people, it correlates with their amount of body fat.

An adult who has a BMI between 25 and 29.9 is considered overweight.

An adult who has a BMI of 30 or higher is considered obese. Over 40 is morbidly obese.

There has been a resurgence of these diet plans in response to physicians and patients seeking a quick and effective weight management tool. The liquid diet supplements of today claim to have a balanced nutritional profile containing complete protein, carbohydrates, fats, and essential vitamins and minerals.

A variety of program choices are now available to those seeking weight loss through a fasting plan from Slim-fast which is available at most any retailer, to the medically supervised programs such as HMR, Optifast, and Medifast. While Slim-Fast meals may be a simpler option for those looking to lose 5-10 pounds, the medically supervised program are more appropriate for those looking to lose a significant amount of weight as health indicators like blood pressure, liver enzymes, and iron levels will be monitored for safe levels. Choosing to purchase these items on-line to do at home can be a risky choice for those with pre-existing health concerns such as heart disease or diabetes.

Why are these diets so effective for weight loss?

Calories are simply measurements of energy, and it takes a reduction of 3,500 calories to lose a pound. Reducing the calorie intake of an adult to 400-1200 calories a day, especially when a typical daily total may have been upwards of 3,000-4,000 calories, will cause a reduction in body weight. Because the prescribed diet typically limits the patient’s choices to a handful of shakes, soups, or pre-prepared meals this limits the number of choices available and keeps the dieter on the fast track to weight loss which averages 3-4 pounds per week after the first two weeks.

Typically the newer, revamped liquid diet programs such as Optifast, Medifast, and HMR consist of:

• a 3 month fasting period (420-800 calories a day in liquid shakes)
• a “refeeding” stage where fruits, vegetables, and lean meats are added back into the diet and may still include the liquid supplements.
• and a maintenance stage where patients eat sensibly independently

This three-tiered method is used in conjunction with an exercise program, nutrition and behavioral change education, and support groups, and are quite effective when adhered to by the patient. Compliant dieters can see a reduction in blood lipids, blood sugars, and blood pressure, and some patients on medications treating diabetes, cholesterol, or blood pressure may also see a reduction in or elimination of these medications.

Challenges of Very Low Calorie Diets

The effectiveness of Very Low Calorie Diets is controlled by the adherence of the patient. This can be challenging for a person whose lifestyle habits have allowed them to gain enough weight to raise their BMI to an unhealthy level. Holidays and other occasions centered around food, and even daily occurrences like the office candy bowl, can challenge even the most resolute dieter.

To maintain the weight lost during the three tiered program, a dieter must be vigilant with food choices, regular exercise and activity, stress management, and control of their own environment as it relates to food. Neglecting one or more of these key components is sure to result in regaining at least a portion of the lost weight.

Potential side effects of a liquid diet

If quality meal replacements are not used or the specific meal requirements and supplementation of vitamins or fiber is not adhered to, side effects including fatigue, dizziness, hair loss, gallstones, cold intolerance, electrolyte imbalance, heart damage, and a loss of lean muscle tissue.. A lack of fiber can lead to constipation and other digestive ailments.

How do I know if a liquid diet is right for me?

Very Low Calorie Diets are intended for those in medical need of significant weight loss and change in behavior in the area of food and nutrition. Because of the potential health risks, all Very Low Calorie Diets should be discussed with your physician, supervised by qualified medical professionals, and contain a behavioral and educational component leading the patient towards a healthier lifestyle.