Author

Callum Hartmann

Callum Hartmann is a senior writer at Biology Insights specializing in dermatological health. Living in Tacoma, Washington, he applies scientific training to explain surface symptoms affecting the skin, nails, and lips. Hartmann worked on a fashion magazine copy desk and studied science journalism, having received a bachelor’s degree in communications.

Why Do I Have an Indent on My Forehead?Skin & Hair
What Causes Nails to Turn Purple?Skin & Hair
What Is This Bubble on My Finger? Common Causes Skin & Hair
Why Did I Wake Up With a Swollen Lip?Skin & Hair
How to Heal a Sore in the Corner of Your Mouth Skin & Hair
Why Does the Skin on My Lips Keep Peeling?Skin & Hair
Why Is My Bottom Lip Peeling and How Do I Fix It?Skin & Hair
Why Is There a Red Spot on My Lip?Skin & Hair
How to Assess Cyanosis in Dark Skin Tones Healthcare
Why Your Eyelashes Fall Out and When to Worry Eyes & ENT
Why Do My Lips Feel Chapped but They Aren’t?Skin & Hair
Why Are My Lips Dark? Causes and When to Worry Skin & Hair
Why Are My Lips Black and I Don’t Smoke?Skin & Hair
What Causes a Bare Spot on the Tongue?Dental
How to Heal a Scab on Your Lip Faster Skin & Hair
What Causes Discoloration Around the Mouth?Skin & Hair
Why the Corner of Your Mouth Hurts and How to Fix It Skin & Hair
Why Is the Corner of My Mouth Cracking: Causes & Fixes Skin & Hair
Bruise on Lip: Causes, Healing Stages, and Care Strategies Skin & Hair
Why Is One Side of My Face Hot?Skin & Hair
How to Get Rid of a Scab on Your Lip Skin & Hair
How to Treat Sunburnt Lips: Soothe and Heal Fast Skin & Hair
What Color Should Lips Be? What Changes Mean Skin & Hair
Why Is There a Brown Spot on My Lip?Skin & Hair
Why Are My Lips Dry Around the Edges?Skin & Hair
Why Does My Tongue Look Purple? Possible Causes Dental
Why Is My Lunula So Big? Causes of a Large Lunula Skin & Hair
Why Is My Head Shaped Weird? Causes & When to Worry Bones & Muscles
Why Is My Eyebrow Hurting? Causes and What to Do Bones & Muscles
How to Get Rid of a Blood Blister on Your Lip Skin & Hair