Blog
News, research and guides
348 articles from our editorial and science team.
GuidesT3 and T4: Is Combining Thyroid Hormones Worth It Instead of Levothyroxine Alone?
Some hypothyroidism patients, despite normal TSH on levothyroxine alone, still report fatigue and brain fog — and look for an answer in combined T4+T3 therapy. We check what a meta-analysis of 16 randomized trials shows before you decide to ask your doctor for a treatment change.
PZdr Piotr Zieliński11 min
August 22, 2026
GuidesTRT and the Liver — Does Injectable Testosterone Actually Damage It?
"Testosterone destroys your liver" is one of the most repeated warnings about TRT — and one of the least accurate. We explain where the fear comes from, why the route of administration is absolutely decisive here, and what the research on injections, gel, and pills actually shows.
PZdr Piotr Zieliński13 min
August 20, 2026
ResearchLongevity Vitamins: Which Supplements Actually Have Real Scientific Evidence Behind Them
Every supplement shelf promises a longer life in every capsule, but the hard data from large clinical trials tells a far more measured story. We go through which vitamins genuinely extend healthy lifespan in people with a real deficiency, and which — despite their popularity — have no supporting evidence at all, or worse, evidence of no benefit.
AKdr Anna Kowalczyk15 min
August 20, 2026
GuidesBiohacking for Beginners — 10 Habits Worth Starting With
Before you buy your first gadget or supplement stack, start where the evidence is strongest: sleep, strength training, movement, food, and bloodwork. A practical guide to ten habits that give you the biggest return for the smallest investment.
AKdr Anna Kowalczyk13 min
August 20, 2026
GuidesNMN vs NAD+ vs Resveratrol — What Actually Extends Life?
Three of the biggest names in longevity, one shared hypothesis, and a very different level of evidence in humans for each. An honest comparison of mechanism, clinical trial quality, and monthly cost — with no marketing rounding up.
PZdr Piotr Zieliński14 min
August 20, 2026
GuidesVitamin D3 and Longevity — Does a Deficiency Shorten Your Life?
Low vitamin D levels correlate with higher mortality across dozens of observational studies, yet the massive randomized VITAL trial found no evidence that supplementation extends life in people without a deficiency. We break down this apparent contradiction piece by piece.
PZdr Piotr Zieliński13 min
August 20, 2026
GuidesSleep Biohacking — How Better Sleep Extends Your Life
Sleep tends to get treated as dead time, something to get through on the way to a productive morning. The epidemiological data says otherwise: both too little and too much sleep are linked to higher mortality risk, and sleep regularity turns out to matter more for survival than the raw number of hours. We gather what's actually known about sleep and longevity, and explain which sleep-biohacking habits actually have research behind them.
JWJulia Wiśniewska14 min
August 20, 2026
GuidesWhich Magnesium Should You Choose? Glycinate, Citrate or Lactate — Comparing the Forms
The supplement shelf can be overwhelming: glycinate, citrate, lactate, oxide, chelate... We compare the most popular forms of magnesium for absorption, price, and what each one is actually best suited for.
PZdr Piotr Zieliński10 min
August 18, 2026
Expert opinionAdaptogen Ranking: Which One Works Best for Stress, Sleep and Energy
Ashwagandha, rhodiola, ginseng, eleuthero — they're all called 'adaptogens', but they have different mechanisms and different strengths. We sort out which one fits which context, based purely on the strength of the available evidence.
MNMichał Nowak11 min
August 18, 2026
GuidesWhich Collagen Should You Choose? Type I, II and III — What the Research Actually Says
Collagen is one of the most commonly bought supplements in Poland, yet few people know that 'collagen' isn't a single substance — it's a family of proteins with different uses. We explain the difference and help you pick the right type.
AKdr Anna Kowalczyk10 min
August 18, 2026
GuidesMelatonin, Magnesium, or L-Theanine? Comparing Sleep Supplements
The three most popular over-the-counter options for better sleep — and each works through a completely different mechanism. We look at which situation calls for which one, instead of reaching for all three at once.
JWJulia Wiśniewska10 min
August 18, 2026
Expert opinionNootropics Ranking: Focus Substances With the Strongest Evidence
The 'brain booster' market is full of promises with nothing to back them up. We've compiled the nootropics that actually have randomized clinical trials behind them, ranked by real strength of evidence — not social-media popularity.
MNMichał Nowak11 min
August 18, 2026
ResearchVitamin D3 or D3 + K2? What the Research Says About Combining Them
Vitamin D3 is the most commonly supplemented nutrient in Poland, and more and more products are now pairing it with vitamin K2. We check whether that combination is actually backed by science, or mostly a marketing hook.
PZdr Piotr Zieliński9 min
August 18, 2026
Expert opinionFunctional Mushroom Ranking: Which Ones Have the Strongest Scientific Evidence
Reishi, shiitake, lion's mane, cordyceps, chaga... The VitMode knowledge base covers more than 50 species of medicinal mushrooms. We picked the five with the most solid evidence base and ranked them by specific use case.
AKdr Anna Kowalczyk9 min
August 18, 2026
GuidesIntermittent Fasting 16:8, 18:6, or OMAD? Which Eating Window to Choose
All three protocols restrict your eating window, but they differ enough that not every one suits everyone. We compare them on how hard they are to implement, the effects they produce, and who each variant makes the most sense for.
JWJulia Wiśniewska10 min
August 18, 2026
ResearchCreatine Monohydrate or HCl? Do the Pricier Forms Actually Make Sense
Monohydrate, HCl, malate, buffered creatine — the supplement shelf keeps growing with more options at higher prices. We check whether the newer forms actually outperform the oldest, best-studied one: plain monohydrate.
PZdr Piotr Zieliński9 min
August 18, 2026
Expert opinionTestosterone Supplements: A Ranking of What Actually Works
The 'testosterone booster' market is built mostly on promises with nothing behind them. We checked the evidence behind the most popular ingredients and ranked them from those with real potential down to pure marketing.
PZdr Piotr Zieliński11 min
August 18, 2026
GuidesLow Testosterone: 12 Symptoms Men Often Don't Connect to Their Hormones
Fatigue, a flatter mood, trouble building fitness despite training — most men blame these on age, stress, or a lack of willpower. We look at which symptoms are actually worth linking to low testosterone, and why none of them, on its own, proves anything.
PZdr Piotr Zieliński12 min
August 15, 2026
GuidesHow to Raise Testosterone Naturally? What Actually Works vs. What's Marketing
The 'testosterone booster' market is worth billions, and most of it does nothing for a man with a normal hormone level. We check what real clinical trials say — from sleep and training to vitamin D, zinc, and ashwagandha — and separate genuine effect from marketing copy.
PZdr Piotr Zieliński13 min
August 15, 2026
GuidesTRT and Fertility: Can Testosterone Therapy Cause Infertility?
Testosterone replacement therapy can suppress sperm production even in men with a 'perfect' blood testosterone result — we explain the mechanism, the real scale of the problem, and the concrete options for men who want to have children.
PZdr Piotr Zieliński12 min
August 15, 2026
GuidesHow Long Does TRT Last? Is Testosterone Therapy for Life?
For most men with confirmed primary hypogonadism, TRT is a lifelong therapy — but in some with functional hypogonadism, it's possible to fix the underlying cause and return to natural production. We explain what this depends on, and what living on TRT for years actually means.
PZdr Piotr Zieliński11 min
August 15, 2026
GuidesTRT and Libido/Erections: Does Testosterone Really Improve Your Sex Life?
Testosterone raises libido more reliably than anything else in this therapy, but erections are a different story entirely — in many men over 40, normalizing the hormone alone won't fix the problem if something other than a testosterone deficiency is behind it.
PZdr Piotr Zieliński12 min
August 15, 2026
ResearchTRT and the Prostate: Does Testosterone Increase Prostate Cancer Risk?
For eighty years, medicine believed testosterone 'fed' prostate cancer, and that any rise in it was dangerous. Newer evidence forces a major narrowing of that rule — but not in the same way for every man.
PZdr Piotr Zieliński12 min
August 15, 2026
GuidesTRT Side Effects: What Should You Actually Worry About?
Internet forums warn of prostate cancer and heart attacks, while for most patients the real everyday issue is thicker blood and acne. We've sorted TRT's side effects by actual risk — not by what sounds the most terrifying.
PZdr Piotr Zieliński13 min
August 15, 2026