- Acute Flaccid Myelitis
- Alzheimer’s Disease
- Arteriovenous Malformations
- Attention Deficit Hyperactivity Disorder
- Back Pain
- Brain Aneurysm
- Brain Tumors
- Carpal Tunnel Syndrome
- Childhood Brain Tumors
- Delirium
- Dementia
- Hemorrhagic Stroke
- Ischemic Stroke
- Memory
- Meningitis
- Mild Cognitive Impairment
- Movement Disorders
- Multiple Sclerosis
- Neuroblastoma
- Neuromuscular Disorders
- Parkinson’s Disease
- Polio and Post-Polio Syndrome
- Speech and Language Problems in Children
- Stroke
- Transient Ischemic Attack
- Tremor
- Walking Problems
- West Nile Virus
- A1C
- Blood Glucose
- Diabetes
- Diabetes and Pregnancy
- Diabetes Complications
- Diabetes in Children and Teens
- Diabetes Medicines
- Diabetes Type 1
- Diabetes Type 2
- Diabetic Diet
- Diabetic Eye Problems
- Diabetic Foot
- Diabetic Heart Disease
- Diabetic Kidney Problems
- Diabetic Nerve Problems
- How to Prevent Diabetes
- Hyperglycemia
- Metabolic Syndrome
- Prediabetes
- Abortion
- Breast Cancer
- Breast Diseases
- Breast Reconstruction
- Breastfeeding
- Cervical Cancer
- Cervical Cancer Screening
- Cesarean Delivery
- Childbirth
- Ectopic Pregnancy
- Endometriosis
- Female Infertility
- Health Problems in Pregnancy
- High Blood Pressure in Pregnancy
- HIV and Pregnancy
- Hormone Replacement Therapy
- HPV
- Hysterectomy
- Infections and Pregnancy
- Mammography
- Mastectomy
- Menopause
- Menstruation
- Miscarriage
- Ovarian Cancer
- Ovarian Cysts
- Ovarian Disorders
- Pelvic Floor Disorders
- Pelvic Inflammatory Disease
- Pelvic Pain
- Period Pain
- Polycystic Ovary Syndrome
- Pregnancy
- Pregnancy and Drug Use
- Pregnancy and Opioids
- Premenstrual Syndrome
- Prenatal Care
- Prenatal Testing
- Primary Ovarian Insufficiency
- Sexual Problems in Women
- Stillbirth
- Teenage Pregnancy
- Trichomoniasis
- Tubal Ligation
- Uterine Cancer
- Uterine Diseases
- Uterine Fibroids
- Vaginal Bleeding
- Vaginal Cancer
- Vaginal Diseases
- Vaginitis
- Vulvar Cancer
- Vulvar Disorders
- Yeast Infections
- Alcohol
- Calcium
- Child Nutrition
- Cholesterol
- Cholesterol Levels: What You Need to Know
- Cholesterol Medicines
- DASH Eating Plan
- Eating Disorders
- Food Allergy
- HDL: The “Good” Cholesterol
- High Cholesterol in Children and Teens
- How to Lower Cholesterol
- How to Lower Cholesterol with Diet
- Infant and Newborn Nutrition
- LDL: The “Bad” Cholesterol
- Malabsorption Syndromes
- Nutrition for Older Adults
- Pregnancy and Nutrition
- Toddler Nutrition
- Triglycerides
- VLDL Cholesterol
- Alpha-1 Antitrypsin Deficiency
- Ataxia Telangiectasia
- Brain Malformations
- Cerebral Palsy
- Charcot-Marie-Tooth Disease
- Chiari Malformation
- Cleft Lip and Palate
- Color Blindness
- Congenital Heart Defects
- Craniofacial Abnormalities
- Cystic Fibrosis
- Ehlers-Danlos Syndrome
- Fetal Alcohol Spectrum Disorders
- Friedreich Ataxia
- Genetic Counseling
- Hemophilia
- Huntington’s Disease
- Hydrocephalus
- Muscular Dystrophy
- Neural Tube Defects
- Neurofibromatosis
- Newborn Screening
- Osteogenesis Imperfecta
- Prader-Willi Syndrome
- Pregnancy and Medicines
- Rett Syndrome
- Sickle Cell Disease
- Spina Bifida
- Spinal Muscular Atrophy
- Tay-Sachs Disease
- Tourette Syndrome
- Tuberous Sclerosis
- Usher Syndrome
- Acute Lymphocytic Leukemia
- Allergy
- Animal Bites
- Ankylosing Spondylitis
- Aplastic Anemia
- Asthma
- Asthma in Children
- Childhood Leukemia
- Childhood Vaccines
- Chronic Lymphocytic Leukemia
- COVID-19 Vaccines
- Cryptosporidiosis
- Eosinophilic Disorders
- Eosinophilic Esophagitis
- Giant Cell Arteritis
- Hay Fever
- HIV
- HIV and Infections
- HIV in Women
- Hodgkin Lymphoma
- Infectious Diseases
- Infectious Mononucleosis
- Juvenile Arthritis
- Kawasaki Disease
- Lymphedema
- Lymphoma
- Multiple Myeloma
- Pemphigus
- Pneumocystis Infections
- Rheumatoid Arthritis
- Scleroderma
- Sjogren’s Syndrome
- Tonsillitis
- Vaccines
- Viral Infections
- Adhesions
- Ankle Injuries and Disorders
- Arm Injuries and Disorders
- Back Injuries
- Brachial Plexus Injuries
- Burns
- Chest Injuries and Disorders
- Concussion
- CPR
- Dislocated Shoulder
- Dislocations
- Elbow Injuries and Disorders
- Eye Injuries
- Facial Injuries and Disorders
- Finger Injuries and Disorders
- Foot Injuries and Disorders
- Fractures
- Hand Injuries and Disorders
- Heel Injuries and Disorders
- Hip Injuries and Disorders
- Inhalation Injuries
- Insect Bites and Stings
- Jaw Injuries and Disorders
- Knee Injuries and Disorders
- Leg Injuries and Disorders
- Mosquito Bites
- Neck Injuries and Disorders
- Rotator Cuff Injuries
- Shoulder Injuries and Disorders
- Spinal Cord Injuries
- Sprains and Strains
- Tick Bites
- Toe Injuries and Disorders
- Traumatic Brain Injury
- Wrist Injuries and Disorders
- Acute Bronchitis
- Bird Flu
- Chronic Bronchitis
- COPD
- COVID-19 (Coronavirus Disease 2019)
- Croup
- E-Cigarettes
- Fistulas
- Flu
- Granulomatosis with Polyangiitis
- H1N1 Flu (Swine Flu)
- Legionnaires’ Disease
- Lung Cancer
- Mesothelioma
- Pneumonia
- Pulmonary Hypertension
- Respiratory Syncytial Virus Infections
- Sleep Apnea
- Smoking
- Tuberculosis
- Whooping Cough
- Anatomy
- Assisted Reproductive Technology
- Birth Control
- Chlamydia Infections
- Circumcision
- Erectile Dysfunction
- Genital Herpes
- Genital Warts
- Gonorrhea
- Herpes Simplex
- Infertility
- Male Infertility
- Penis Disorders
- Prostate Cancer
- Prostate Cancer Screening
- Prostate Diseases
- Reproductive Hazards
- Sexual Health
- Sexual Problems in Men
- Sexually Transmitted Diseases
- Syphilis
- Testicular Cancer
- Testicular Disorders
- Vasectomy
- Abdominal Pain
- Bad Breath
- Bleeding
- Breathing Problems
- Bruises
- Chest Pain
- Choking
- Chronic Pain
- Constipation
- Cough
- Diarrhea
- Dizziness and Vertigo
- Edema
- Fainting
- Fever
- Frostbite
- Gas
- Gastrointestinal Bleeding
- Headache
- Heartburn
- Heat Illness
- Hives
- Hypothermia
- Indigestion
- Itching
- Jaundice
- Nausea and Vomiting
- Pain
- Rare Diseases
- Raynaud’s Disease
- Sciatica
- Speech and Communication Disorders
- Stuttering
Hair Problems
Summary
The average person has 5 million hairs. Hair grows all over your body except on your lips, palms, and the soles of your feet. It takes about a month for healthy hair to grow half an inch. Most hairs grow for up to six years and then fall out. New hairs grow in their place.
Hair helps keep you warm. It also protects your eyes, ears and nose from small particles in the air. Common problem with the hair and scalp include hair loss, infections, and flaking.
National Institute of Arthritis and Musculoskeletal and Skin Diseases
Related Issues
- African-American Hair: Tips for Everyday Care American Academy of Dermatology
- Formaldehyde in Hair Smoothing Products: What You Should Know Food and Drug Administration
- Hair Dye and Hair Relaxers Food and Drug Administration
- How to Stop Damaging Your Hair American Academy of Dermatology
Patient Handouts
- Aging changes in hair and nails Medical Encyclopedia
- Dry hair Medical Encyclopedia
- Excessive or unwanted hair in women Medical Encyclopedia
- Folliculitis Medical Encyclopedia
- Trichorrhexis nodosa Medical Encyclopedia
Find an Expert
- American Academy of Dermatology American Academy of Dermatology
- National Institute of Arthritis and Musculoskeletal and Skin Diseases National Institute of Arthritis and Musculoskeletal and Skin Diseases
Genetics
- Autosomal recessive hypotrichosis: MedlinePlus Genetics National Library of Medicine
- Keratoderma with woolly hair: MedlinePlus Genetics National Library of Medicine
- Monilethrix: MedlinePlus Genetics National Library of Medicine
- Uncombable hair syndrome: MedlinePlus Genetics National Library of Medicine
Clinical Trials
- ClinicalTrials.gov: Dandruff National Institutes of Health
- ClinicalTrials.gov: Hair Diseases National Institutes of Health
Start Here
- Common Hair Problems VisualDX
Specifics
- Folliculitis Mayo Foundation for Medical Education and Research
- Hirsutism American Academy of Family Physicians
- Ingrown Hair Mayo Foundation for Medical Education and Research
Images
- Folliculitis VisualDX
- Hot Tub Rash (Pseudomonas Folliculitis) VisualDX
- Pilar Cyst VisualDX
- Pseudofolliculitis Barbae VisualDX
Women
- Hirsutism Endocrine Society
- Hirsutism and Polycystic Ovarian Syndrome American Society for Reproductive Medicine
Encyclopedia
- Hot tub folliculitis Medical Encyclopedia
- Skin and hair changes during pregnancy Medical Encyclopedia
Statistics and Research
- How Stress Causes Gray Hair National Institutes of Health
Treatments and Therapies
- Laser Hair Removal VisualDX
Journal Articles
Teenagers
- Removing Pubic Hair (For Young Women) Boston Children’s Hospital
Children
- Why Does Hair Turn Gray? Nemours Foundation
- Your Hair Nemours Foundation