Topic
Skin health
How skin conditions and screening are evaluated, separating what the evidence supports from marketing.
This page collects every article by Dr. Damon Tojjar in this topic. For all topics see browse by topic, and for the source-anchored record see damontojjar.com/record.
Articles in this topic (22)
- How Good Are the ABCDE Rule and Dermoscopy at Catching Melanoma?
The ABCDE rule and dermoscopy catch a lot of melanoma, but neither is a magic filter, and how much they help depends heavily on who is using them. In the largest...
- How the 2024 Acne Guidelines Grade Treatments and Fight Antibiotic Resistance
The 2024 American Academy of Dermatology (AAD) acne guidelines grade every treatment on two separate axes rather than one: how strongly the therapy is recommended,...
- Which Actinic Keratosis Treatment Works Best? Reading the Head to Head Trial
Across the four field therapies compared directly in the New England Journal of Medicine, one option separated itself from the rest. In a randomized trial of 624...
- How the Eczema Guidelines Rank Biologics and JAK Inhibitors
The 2024 American Academy of Dermatology (AAD) guideline on systemic treatment of atopic dermatitis gives its strongest endorsement, a "strong recommendation," to...
- Does Sunscreen Cause Vitamin D Deficiency? What the Evidence Says
The tension in one questionIn a laboratory dish, sunscreen does exactly what its chemistry promises: it absorbs or scatters ultraviolet B, the same wavelengths the...
- Does Sunscreen Actually Prevent Melanoma? Reading the One Randomized Trial
Only one randomized controlled trial has ever measured whether sunscreen prevents melanoma, and it points cautiously toward yes. In the Nambour trial in Queensland,...
- Why Daily Baby Moisturizer Did Not Prevent Eczema in Large Trials
Two large, well-conducted randomized trials set out to prove a tidy idea, that rubbing moisturizer into a baby's skin every day from birth would head off eczema...
- How to Read the Evidence Behind the First FDA Cleared AI Skin Cancer Device
The first artificial-intelligence device the FDA authorized to help detect skin cancer in a primary care setting, granted through the De Novo pathway in January...
- What the USPSTF I Statement on Skin Cancer Screening Actually Means
The 2023 grade I from the US Preventive Services Task Force is not a ruling that skin cancer screening does not work. It means the evidence is too thin, too...
- Is Melanoma Overdiagnosed? What Rising Incidence and Flat Mortality Reveal
Melanoma diagnoses in the United States have risen roughly sixfold over the past four decades, yet the death rate barely moved for most of that period. That...
- What the Evidence Really Shows About Isotretinoin, Depression, and Bowel Disease
Large, carefully controlled studies have not found that isotretinoin causes depression, suicide, or inflammatory bowel disease. A 2024 JAMA Dermatology...
- When Is Mohs Surgery the Right Choice? How the Appropriate Use Criteria Were Built
Mohs micrographic surgery is the right choice when a skin cancer combines a high-risk location, aggressive or poorly defined behavior, or a patient whose immune...
- Is Psoriasis Really a Whole Body Disease? Reading the Cardiovascular Evidence
Yes, psoriasis is reasonably described as a whole body disease, and the cardiovascular data are the strongest evidence for that label. People with psoriasis,...
- How the Evidence Guides Rosacea Treatment by Phenotype
The strongest current evidence recommends matching rosacea treatment to the specific features a person actually has, such as redness, flushing, inflammatory bumps,...
- What a Sentinel Node Biopsy Tells You and What the MSLT Trials Changed
A sentinel lymph node biopsy is a staging test, not a treatment. It tells you whether the first lymph node draining a melanoma already contains tumor cells, which...
- Why Melanoma Is Deadlier in Darker Skin Even Though It Is Rarer
Melanoma is far less common in darker skin, yet it takes a larger share of the people it reaches. The reason is not that pigment makes the tumor more aggressive by...
- Why Smartphone Melanoma Apps Miss Cancers a Dermatologist Would Catch
Smartphone apps that promise to screen your moles for melanoma consistently miss cancers that a trained clinician would flag, and the best available evidence says...
- Sunscreen Chemicals in Your Blood: What the FDA Absorption Studies Do and Do Not Show
Yes. In two maximal-use pharmacokinetic trials published in JAMA, several common chemical sunscreen filters were absorbed through the skin into the bloodstream at...
- How Accurate Is Teledermatology Compared With an In-Person Visit
Teledermatology matches an in-person diagnosis roughly three times out of four, and the asynchronous "store-and-forward" version performs about as well as a live...
- Why the USPSTF Backs Sun Protection Counseling for Young People but Not Everyone
Why the same advice earns a B for a teenager and only a C for a middle-aged adultThe US Preventive Services Task Force gives sun protection counseling a grade B for...
- What a Skin Biopsy Actually Decides: Breslow Depth and Melanoma Staging
The number that sets the courseWhen a suspicious mole is removed and sent to pathology, the most consequential figure on the report is a single measurement in...
- What SPF Really Measures, and Why 100 Is Not Twice as Good as 50
SPF is a ratio, not a timer and not a straightforward percentage of the sun blocked. It reports how much more ultraviolet energy your skin can absorb before it...