Pros and Cons of Extreme Weight Loss Diets

If you’re on a diet now or have recently been on one, you’re not alone. An estimated 45 million Americans go on a diet each year. 

The weight loss industry in the United States is booming. Consumers spend $33 billion each year on weight loss products. That’s because 40 percent of adults in the U.S. have obesity and another 32 percent are overweight. Globally, more than 1.9 billion adults are overweight, out of which 650 million adults are obese. 

Although many individuals attempt to lose weight quickly through “extreme” diets, most put on the weight they lose once they start eating regular meals again. In fact, research suggests that roughly 80 percent of people who shed a significant portion of their body fat will not maintain that degree of weight loss for 12 months. Plus, most of these extreme diets come with potentially dangerous side effects. 

What exactly is an extreme diet? It’s a diet intended to make the dieter lose a large amount of body weight in a short amount of time, usually by severely restricting calories. According to the Academy of Nutrition and Dietetics, calorie needs for adult women range from 1,600-2,200 per day; for men, the estimates range from 2,000-3,200 daily.

Some extreme diets restrict the number of calories consumed in a day to as low as 600-800, resulting in a weight loss of seven to 10 pounds in a week. The Centers for Disease Control and Prevention (CDC) recommends individuals attempting to lose weight only lose one to two pounds per week and notes that those who lose weight gradually and steadily are more successful at keeping it off.  

All About Extreme Diets 

The Chemical Diet 

Overview: Promoted as a way to reduce blood sugar levels, this diet is based on the chemical constituents of specific food combinations, which are thought to amplify results and boost fat burning. It consists of three meals per day. 

What You Eat: Lean, non-fried meat, water, eggs, vegetables (tomatoes, spinach, carrots, cucumbers, celery, lettuce), fruits (grapefruit, apples, bananas, oranges, pears, peaches, plums), whole grain toast, some beverages (water, black coffee, unsweetened tea) 

What You Don’t Eat: Some grains (quinoa, couscous, barley, rice, oats, buckwheat), legumes (beans, chickpeas, lentils) and vegetables (sweet potatoes, broccoli, cauliflower, asparagus); oils, snacks, nuts, seeds, dairy products, sweeteners, fruit juice, alcohol 

Pros: Can lead to short-term weight loss 

Cons: Not nutritionally balanced, overly restrictive, increased risk of nutritional deficiencies 

The Raw Food (Raw Paleo) Diet 

Overview: This diet consists of eating anything uncooked or unprocessed. Proponents of it believe cooking or processing foods deprives them of some nutrients. 

What You Eat: Raw red meat, fish, fruits, vegetables, nuts, seeds, sprouted grains, unpasteurized dairy foods, seaweed, purified water 

What You Don’t Eat: Anything processed or cooked 

Pros: Aids in weight loss, may reduce appetite, eliminates highly processed foods and added sugar 

Cons: Overly restrictive, higher risk of food-borne diseases, increased risk of nutritional deficiencies, higher amounts of saturated fat, not recommended for individuals with chronic medical conditions 

The Grapefruit Diet 

Overview: First introduced in the 1930s, this extreme weight loss method limits food intake to 800-1,000 calories per day. There are variations to this diet, but the main instruction is to eat grapefruit or drink grapefruit juice before each meal. 

What You Eat: Grapefruit, salad, eggs, cooked vegetables, most meats, bacon, coffee, tea, water 

What You Don’t Eat: Other fruits, dairy products, grains, starches, added sugar 

Pros: Promotes weight loss of 10 pounds during a 10-12day detox 

Cons: increased risk of anemia, negative interactions with more than 50 medications 

The Cabbage Soup Diet 

Overview: You have to like cabbage to be on this diet, as it requires you to eat the fat-free soup two to three times daily along with some assigned foods. Individuals who follow this diet usually consume 1,000 or fewer calories per day. 

What You Eat: Cabbage soup, assigned daily food 

What You Don’t Eat: Anything not on the diet 

Pros: Promotes weight loss of 10 pounds in one week 

Cons: Overly restrictive, lacks sufficient carbohydrates and protein, not recommended for individuals with diabetes 

The Master Cleanse/Lemonade Diet 

Overview: Sometimes referred to as the maple syrup diet, the Master Cleanse is a liquid-only diet consisting of a lemonade-like beverage, a salt-water drink and herbal laxative tea. Individuals who follow this diet are encouraged to consume six to nine of these drinks per day. 

What You Eat: A lemonade-like beverage, a salt-water drink, and herbal laxative tea 

What You Don’t Eat: Any solid food, alcohol 

Pros: Promotes weight loss of 10 pounds in one week 

Cons: Overly restrictive, fatigue, headaches, dizziness, diarrhea, loss of muscle, bone, and water 

Dangers of Rapid Weight Loss 

Although some individuals want to lose a lot of weight in a short time period, doing so can result in numerous side effects, not the least of which is malnutrition. Malnutrition can lead to short- and long-term health problems, slow recovery from wounds and illnesses and a higher risk of infection. 

Other potential dangers of extreme weight loss diets include dehydration, bone and muscle loss, heart problems, insulin resistance, electrolyte imbalance, fatigue and slowing metabolism. Rapid weight loss can even put you at increased risk for gallstones, which occur in 12-25 percent of people losing large amounts of weight over several months. 

Safer Weight Loss Methods

Even the increasingly popular intermittent fasting weight loss method, which some research suggests may be more beneficial than other diets for reducing inflammation and improving conditions associated with inflammation, comes with temporary side effects, such as hunger, fatigue, insomnia, nausea, and headaches. 

Popular approaches to intermittent fasting include:

  • Alternate-day fasting: Eat a normal diet one day and either completely fast or have one small meal (less than 500 calories) the next day
  • 5:2 fasting: Eat a normal diet five days a week and fast two days a week
  • Daily time-restricted fasting 

Harvard Medical School lists four side effects to watch out for when doing intermittent fasting:

  1.   It may make you feel sick.
  2.   It may cause you to overeat.
  3.   It may cause older adults to lose too much weight.
  4.   It may be dangerous if you’re taking certain medications.

Except for a physician-monitored very low-calorie diet (VLCT) and weight loss (bariatric) surgery, no other diet has been proven to safely work for fast weight loss. Gastric bypass surgery is the most common weight reduction procedure

At VIDA Bariatrics, we offer multiple types of bariatric surgery, including gastric bypass, gastric sleeve, gastric banding and more. See if you’re a candidate for weight loss surgery, and learn about the weight loss surgery travel packages we offer!


Dr. Gabriela Rodriguez specializes in General and Laparoscopic Bariatric Surgery. She brings to VIDA Wellness and Beauty a wealth of experience in bariatrics. Dr. Rodriguez is a founding associate of the Mexican College of General Surgeons. A world-class bariatric surgeon with double certification in the US and Mexico.