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Cortisol face is not real, at least not in the way the internet is currently using it.

The trend goes like this: someone posts a photo, or sends their Instagram pictures to an account online, and is told that because their face looks puffy, their cortisol must be elevated, and here is the thing that will fix it. That last part is worth noticing. When a diagnosis arrives attached to a product, it is usually marketing rather than medicine.

Here is the more useful picture. If a clinician genuinely suspects your cortisol is too high, they do not look at a photograph. They test blood biomarkers and look for real conditions such as Cushing's or specific hormonal imbalances. That is a proper diagnostic pathway, and it exists precisely because you cannot see endocrine function from the outside.

And most facial puffiness has far more ordinary explanations. Most people are a little puffy in the morning simply because of how you have been lying, lymphatic drainage, salt levels, heat, alcohol, poor sleep. In the aesthetic space, previous injections or surgery can also create a little fullness, often under the eyes or across the cheeks. None of that is a hormonal emergency. It is a face, in the morning, behaving like a face.

I am not dismissing the underlying concern, because chronic stress is genuinely worth taking seriously. I am objecting to the diagnostic method, which is a photograph interpreted by someone with something to sell.

If you are worried about your cortisol, that is a conversation with a clinician and a blood test, not a mirror.

What health trend would you most like me to look at next? Ask below.

Stress saves your life or quietly costs it, depending on the type.

Acute stress is good: hard exercise, a sprint, a dose your system adapts to. Chronic psychological stress is different. Always-on fight-or-flight resets your stress thermostat, drags on insulin and hormones, compromises immunity, recovery and sleep.

People reach for supplements and peptides when the first-line fix is often simpler: learn to dial down. As a stem cell doctor, one trial stays with me: circulating stem cells were higher and more functional in people who meditated daily. Fifteen minutes, box breathing, measurable cortisol decline within weeks.

When the brain calms, the body drops into recovery. That is where longevity is built.

Scientists just used AI to reverse ageing in human cells. Worth a careful read.

OpenAI partnered with Retro Biosciences to redesign the Yamanaka factors, the four proteins that can reprogram adult cells back towards a youthful state. Important discovery, but practice has shown they are only part of the picture. Cellular reprogramming is extraordinarily complex, and no single protein holds the answer.

That is where AI earns its place. Scientists can spend twenty years on one protein and its thousands of interactions. Humans cannot read a system that large. AI increasingly can, compressing decades of research into weeks.

Promising direction, still early. Cells in a dish are not a treatment.

More in the video.

Sleep debt cannot be repaid. Three extra hours on Sunday will not restore what the missed nights took.

Deep sleep is the most recovery-productive phase there is: heart resting, blood pressure lower, cortisol dropping, recovery hormones running their clean-up phase. Miss the window and the work simply does not happen.

But life does not always let you choose. Flights, time zones, young children. In those circumstances a thoughtful supplement stack can be a genuine adjunct: magnesium and GABA-supporting compounds, melatonin support. It is why F+NCTION Calm sits in my protocol.

The caveat matters most: never a replacement for the fundamentals. But if five hours is all you will get, optimise those five hours.

Stem cells are not a fat-loss treatment. Worth saying plainly, because the two get bundled together in a way that does not hold up.

What is true is more useful: the habits that support healthy stem cell activity also improve how your body handles fuel. The overlap is not a coincidence.

The conditions, none of them dramatic: sensible fasting rather than a constant surplus, training to build and keep muscle (your metabolic engine), good sleep, lower chronic inflammation, and daily signals like morning light and a little cold exposure.

No shortcut on that list. The unglamorous inputs are the ones with evidence behind them, and they compound.

More in the video.

"Scientists reversed human ageing." Worth reading that headline more carefully.

In 2025 a team engineered an ageing-resistant stem cell by editing FOXO3, a longevity gene, and infused it into elderly monkeys. They reported better memory and brain function, less brain shrinkage and bone loss, with no tumours or rejection. A careful, encouraging result.

Three questions keep claims like this grounded. What species, because monkeys are not humans. What was actually measured, because ageing can mean bone density, cognition or a biological clock. And most importantly, was it safe over time, since improving one system can quietly harm another.

Real reason for optimism, read with clear eyes.

Full thoughts in the video.

Every protein source you eat, rated honestly by a clinical team.

The winners are unfashionable: lean beef, chicken breast, cottage cheese, Greek yoghurt. Complete profiles, high protein per calorie.

The overrated tier is where the money goes. Most protein bars are confectionery with a claim on the wrapper. Oat and almond milk carry almost no protein at all.

And collagen? 2 out of 10. As a dietary protein it's incomplete, and your body doesn't send it where the advert promised.

Full ratings in the video. Comment the protein you eat most and we'll tell you where it ranks.

Can you raise your own stem cell activity without a procedure? Yes, within limits. The levers are unglamorous.

A fast of around 24 hours triggers autophagy: the body clearing damaged cells and prompting regeneration. A genuinely hard 20-minute session pushes repair cells from bone marrow into the bloodstream within hours. And sleep is the multiplier: cutting from 8 hours to 4 roughly halves stem cell migration.

Cold exposure and polyphenols help at the margins. Garnish, not the meal.

Stack all three on the same day and the effect compounds.

Full evidence breakdown in the video. Which one do you neglect most?

Joe Rogan has been talking, again, about stem cells. A full-length rotator cuff tear, no surgery, healed. The kind of headline-friendly outcome that fuels the wrong decisions.

The clinical position has to be careful, and so does the patient.

A single miracle case is not clinical evidence. One outcome does not generalise. Anyone in a regenerative field who tells you otherwise is selling, not diagnosing.

At the same time, biology is remarkable. We have had patients we told honestly we did not expect this to work. Their wider medical team and the patient themselves advocated for trying on a risk-benefit basis. We have seen people for whom every line of training said they needed surgery heal without it.

We cannot fully explain that case by case. When you stimulate biology in the right way, the body sometimes does what the textbook says it should not.

If you are looking at stem cell therapy on the back of a podcast clip, go to a clinician who understands the science, knows the evidence, and is willing to tell you both what they know and what they do not.

This is the future of medicine. It will not arrive faster by being oversold.

There is a complaint that surfaces in clinic far more often than people realise. The post-lunch crash. The dip in energy and focus in the hour or two after a midday meal. Most patients have been told, at some point, that it is simply normal. Clinically, it is worth examining rather than dismissing.

The reflex response in most working environments is to reach for a quick fix. Coffee. A chocolate bar. A protein bar marketed as healthier than it usually is. Each of these gives the system a short pulse of energy and a small dopamine reward, but does very little to address the underlying signal. Repeated often enough, this becomes a snack cycle. Continuous spikes of insulin. A gradual rise in systemic inflammation. Metabolism that becomes progressively less responsive over time. The cost is rarely felt in the moment. It is felt over years.

A more useful interpretation of the afternoon dip is that the body is reporting on the meal that preceded it. Meals weighted heavily towards refined carbohydrate, in clinical observation, are the most common driver. Carbohydrate is ultimately sugar in a slower form, and the glycaemic profile of a typical office lunch is rarely flat.

A reasonable adjustment, depending on individual circumstances, is to build lunch around a protein source and a generous volume of vegetables, with refined carbohydrate kept deliberately low. The pattern that tends to follow is steadier energy through the afternoon, fewer cravings, and a quieter inflammatory profile over the longer term.

The afternoon crash is not a personality trait. It is a signal worth listening to.

What does your typical working lunch currently look like?