InsideOut Institute Logo
Log inAre you at risk?
eClinic
Our world-first eClinic is here. Free, trusted eating disorder support now available anytime, anywhere. No referral. No cost. Backed by experts, built for you.
Resources
/

Physical & Psychological Effects of Anorexia Nervosa

Physical & Psychological Effects of Anorexia Nervosa

Last Reviewed: 01 May 2025

Physical and Psychological Effects of Anorexia Nervosa 

 

As a result of the food restriction and malnutrition that occurs with Anorexia Nervosa, the body is denied the essential nutrients it needs to function normally. This, along with excessive activity/exercise to avoid weight gain, forces the body to slow down its natural processes to conserve what little energy it has, and if left untreated can result in severe medical and mental health problems. In some cases, the condition can be life-threatening. 

 

Physical effects associated with Anorexia Nervosa include: 

 

  • Rapid weight loss or frequent fluctuations in weight 

  • Low iron levels 

  • Poor blood circulation, irregular or slow heart beat, very low blood pressure, sudden cardiac arrest and even heart failure 

  • Menstrual loss or disruption in females 

  • Decreased testosterone in males 

  • Decreased libido 

  • Fertility issues 

  • Poor bone health, increased risk of fractures and breaks 

  • Muscle loss, weakness and fatigue 

  • Weak nailes , thin hair, dry skin 

  • Fainting, headaches or dizziness 

  • Dehydration, kidney failure 

  • Constipation, diarrhoea, abdominal pain 

  • Increased sensitivity to coldness, growth of fine hair, ‘lanugo’, all over the body to keep warm 

 

Psychological effects associated with Anorexia Nervosa include: 

  • Depression 

  • Anxiety 

  • Sleep disturbances 

  • Impaired concentation, decision making 

  • Mood swings, irritability 

  • Preoccupation with food/calories 

  • Obsessive compulsiveness 

  • Intense fear weight gain, or ‘feeling fat’ 

  • Social withdrawal 

  • Suicidal ideation and increased risk of suicide 

 

Children and adolescents are particularly vulnerable to health problems as a result of malnutrition, and long-term consequences can occur due to interrupted growth and pubertal development. Below is a list of complications that should be considered when assessing young people with eating problems: 

 

  • Significant dehydration 

  • Significant deficits in bone mass (leading to osteopaenia and osteoporosis) 

  • Stunted growth 

  • Limited fat mass stores 

  • Delayed or incomplete pubertal development 

  • Psychological complications including depression, anxiety, obsessive compulsive disorder and cognitive impairment 

InsideOut Institute LogoAccreditation icon

Subscribe to our newsletter!

© 2026 InsideOut

InsideOut acknowledges the tradition of custodianship and law of the Country on which the University of Sydney and Charles Perkins Centre campus stands. We pay our respects to those who have cared and continue to care for Country. We are committed to diversifying research and eliminating inequities and discrimination in healthcare. We welcome all people regardless of age, gender, race, size, sexuality, language, socioeconomic status, location or ability.