Top 5 Rankings
Short, structured tests: five products, three weighted criteria, one winner. Links go to Amazon.
Best PDRN Serums and Creams: 6 Products Ranked (2026)
Six PDRN serums and creams compared on published facts: PDRN source, declared strength, niacinamide,…
The 5 Best Collagen Powders, Tested in the Kitchen
Five collagen peptide powders compared on dose, third-party testing, cost per 10 grams and how they…
The 5 Best Melatonin Gummies, Tested for Two Weeks
We tested five melatonin gummies for dose, third-party verification and cost per night. The winner is the…
The 5 Best Vitamin C Serums, Tested for Four Weeks
Five vitamin C serums, four weeks, one winner. We compared L-ascorbic acid strength, stability and price…
All Articles
Eyelash Serum Side Effects: What to Check on the Label
Eyelash serum side effects mostly trace back to one ingredient class. How to spot prostaglandin analogs on the label, and what to do with contact lenses.
Creatine for Women Over 40: What It Does, How Much to Take
Creatine monohydrate for women over 40: what research shows for strength, bone and mood, the water-weight and hair-loss myths, and the right daily dose.
Collagen Supplements: What the Studies Actually Show
Collagen peptides for skin, joints, bone and hair: what 19 trials found, which dose and timing were tested, and how they compare with retinoids.
PDRN vs. Retinol: Which Is Better for Wrinkles After 40?
PDRN vs. retinol compared: what the studies show for wrinkles, whether you can use both, which goes on first, and three products with prices.
Do Eyelash Serums Really Work? What the Evidence Says
Do eyelash serums really work? One prescription drug has trial proof. What peptide serums can realistically do, how long it takes and what to skip.
Melatonin: The Dose Most People Get Wrong (and the Fix)
Most US melatonin products carry 3 to 10 mg; the dose that mimics your own body is 0.3 to 1 mg. What to take, when to take it, and who should skip it.
What Is PDRN? Korea’s Wonder Ingredient, Fact-Checked
What is PDRN? Purified salmon DNA from Korean skincare, explained: what the studies show, what a cream can and cannot do, and how fast it works.
Magnesium: Which Form Actually Absorbs, and for What
Oxide, citrate, glycinate or Epsom salt? What the evidence says about each magnesium form, doses for sleep and migraine, and who should ask a doctor first.
Flu Shot 2026–27: Who Needs It, When, and What It Costs
CDC guidance for the 2026–27 flu season: who needs the shot, the best weeks to get it, which vaccine to ask for after 65, and what it really costs.
Fall Skin Reset: What Changes After Summer, What to Adjust
Why skin turns dry, red and blotchy in fall: indoor humidity under 40%, sun damage surfacing, and a four-question Skin Type Finder for what to change.
Trending
About Medi-Journal
Plain-language health, skin and nutrition reporting for readers over 40. Every article is checked against primary sources: CDC, NIH, FDA and peer-reviewed studies.
Our Top 5 Rankings are short, structured tests: five products bought at retail, three weighted criteria, one winner. Links go to Amazon and may earn us a commission; they never change the ranking.
2022Publishing since
5Products per test
Health Tools
BMI & daily calorie calculator
Body mass index plus the calories you burn at rest and per day, based on the Mifflin-St Jeor equation used in clinical practice. Nothing you enter leaves your browser.
27.0BMI
Overweight1518.5253040
At rest1,346kcal
Maintain1,850kcal
Lose 1 lb/wk1,350kcal
Estimates for adults; BMI does not account for muscle mass. Not medical advice.