Before you do anything, I suggest a look at the complications of these weight loss techniques:

Malnutrition
Dehydration
Electrolyte imbalance, which can cause cardiac arrest or brain damage from a stroke
Hyponatremia
Damaging of the voice
Vitamin and mineral deficiencies
Teeth erosion and cavities, gum disease
Salivary gland swelling (sialadenosis)
Potential for gastric rupture during periods of binging
Esophageal reflux
Irritation, inflammation, and possible rupture of the esophagus
Laxative dependence
Peptic ulcers and pancreatitis
Emetic toxicity due to ipecac abuse
Swelling of the face and cheeks, especially the lower eyelids, due to the high pressure of blood in the face during vomiting; for the same reason Purpura can occur, a rash caused by burst blood vessels.
Callused or bruised fingers
Dry or brittle skin, hair, and nails, or hair loss
Lanugo
Edema
Muscle atrophy
Decreased or increased bowel activity
Digestive problems that may be triggered, including celiac and Crohn's disease
Low blood pressure (hypotension)
Orthostatic hypotension
High blood pressure (hypertension)
Iron deficiency
Anemia
Hormonal imbalances
Hyperactivity
Depression
Insomnia
Amenorrhea
Infertility
High risk pregnancy, miscarriage, still-born babies
Diabetes
High blood sugar (hyperglycemia)
Ketoacidosis
Osteoporosis
Arthritis
Russell's sign (scarring on the knuckles or back of the hand due to self-induced vomiting over long periods of time)
Weakness and fatigue also along with depression
Cancer of the throat or cancer of the voice box
Liver failure
Kidney infection and failure
Heart failure, heart arrhythmia, angina
Seizure
Paralysis
Death caused by heart attack or heart failure; lung collapse; internal bleeding, stroke, kidney failure, liver failure; pancreatitis, gastric rupture, perforated ulcer, depression and suicide. Stunted growth
Endocrine disorder, leading to cessation of periods in girls (amenorrhoea)
Decreased libido; impotence in males
Starvation symptoms, such as reduced metabolism, slow heart rate (bradycardia), hypotension, hypothermia and anemia
Abnormalities of mineral and electrolyte levels in the body
Thinning of the hair
Growth of lanugo hair over the body
Constantly feeling "cold"
Zinc deficiency
Reduction in white blood cell count
Reduced immune system function
Pallid complexion and sunken eyes
Creaking joints and bones
Collection of fluid in ankles during the day and around eyes during the night
Tooth decay
Constipation
Dry skin
Dry or chapped lips
Poor circulation, resulting in common attacks of 'pins and needles' and purple extremities
In cases of extreme weight loss, there can be nerve deterioration, leading to difficulty in moving the feet
Headaches
Brittle fingernails
Bruising easily
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