Some people are willing to go to extremes to obtain their ideal body. Plastic surgery has exploded in recent decades with thousands of people willing to go under the knife to obtain the perfect nose, fewer wrinkles or fuller lips. Operations that aim to decrease a person’s weight have also grown in popularity. Liposuction, fat grafting and gastric bypass surgeries have made the news and been touted by various celebrities. Most people, however, do not have the money or desire to pay for surgical weight loss procedures. Instead, they rely on the good old-fashioned diet.

Diets are far less invasive than surgeries, but they are not necessarily safer. While there is no harm in cutting back on the snacks or keeping cookies out of the house, some dieters go to truly incredible lengths to get what they see as the perfect figure. Some of those lengths can cause permanent harm. Here are some of the world’s most dangerous diets.

Paleolithic Diet

Also called the Cave Man Diet or the Stone Age Diet, the Paleolithic Diet involves eating only nuts, fruits, vegetables, fish and wild meats. The idea behind the diet is that a person should only consume what their ancestors evolved to eat. While this may be perfectly fine theoretically, Cro-Magnons were eating what was available and were thus more prone to suffering from disease, vitamin deficiencies and other health problems. The Paleolithic Diet opens the door for those old dangers. Cutting whole grains and dairy out of a person’s diet means they are missing out on key nutrients that are necessary to keep the human body functioning properly. This can lead to malnutrition, vitamin deficiencies and all the maladies that go with them.


Mono-Diets are diets that require a person to eat only one food for 30 days. Two of the most famous forms of the mono-diet are the Grapefruit Diet and the Cabbage Soup Diet, though the Banana Diet was made briefly famous as well. These single-food diets are dangerous for the same reason as the Paleolithic Diet: they deprive the body of key vitamins and nutrients that are essential for normal functioning. In addition to leading to nutrient deficiencies, Mono-Diets tend to be starvation diets. Dieters take in as little as 800 calories a day, nearly half of the safe lower limit for caloric intake.

Master Cleanse

This has become a wildly popular diet ever since Beyonce publically praised it. The Master Cleanse diet involves drinking nothing but water mixed with lemon juice, cayenne pepper and maple syrup for ten to 40 days. In addition to leading to obvious nutritional deficiencies, the Master Cleanse has been known to lead to problematic blood-sugar levels as the body struggles to function without fuel.

The Master Cleanse is a starvation diet where dieters lose weight by simply refusing to take in even the minimal amount of calories needed for normal bodily functioning. Starvation diets leave dieters feeling lethargic, ill and suffering from hunger pains, and most starvation dieters end up gaining weight in the long run. This is because when dieters deny the body the calories it needs, their metabolism slows in an effort to conserve caloric fuel and may not speed up once the dieter returns to normal eating habits. Starvation diets like the Master Cleanse, Baby Food Diet and various liquid diets also lead to a loss of skeletal muscle which burns a great deal of calories. In extreme cases, starvation diets can cause to the body to begin to break down and consume its own organs in an effort to remain functioning.

Nicotine Diet

It should not surprise anyone that a diet relying on an addictive drug in dangerous. The Nicotine Diet, also called the Cigarette Diet or the Supermodel Diet, uses nicotine to suppress a person’s appetite. This is most commonly done through smoking cigarettes, though nicotine patches and gum are sometimes used. Beyond the risk of developing mouth, throat or lung cancer from cigarettes, nicotine is a highly addictive substance. Even if a dieter used nicotine gum or patches, they would still end up hooked on an addictive drug potentially for the rest of their life.

Ketogenic Diet

The Ketogenic Diet is extremely dangerous. The diet attempts to force the dieter’s body into ketosis, a process by which the body burns fat for energy. This naturally occurring process is usually triggered during periods of extreme food shortage as the body is forced to consume itself to survive. The Ketogenic Diet works to trigger this process by having practitioners consume a high-fat diet that is low in carbohydrates. Some forms of the diet call for less than ten percent of a person’s diet to come from protein or carbohydrates. Beyond the obvious dangers of cutting entire food groups from a person’s diet, the Ketogenic Diet was developed in the 1920’s and 30’s as a way to alter a person’s brain chemistry. It was meant to control epileptic seizures before modern drugs were developed and is still prescribed today for epileptics whose seizures do not respond to medication. The diet is meant to be prescribed by a physician and carefully monitored by a licensed dietician. It is not to be undertaken on a whim by someone wanting to shed some post-holiday weight.