General health
😮💨 What Vaping Does To Human Lung
A new study (PMID: 42579367) has found that exposure to vaping in a lab kills human lung cells after just 24 hours of exposure. Meanwhile animal data shows similar damage can persist for 10 days after the last exposure.
Normally, I would hesitate to write about research not conducted on humans.
You are not a mouse, nor a pile of lung cells lying in a Petri dish.
But given the pervasiveness of vaping and the fact that human evidence will only come from the unfortunate natural experiments many people are conducting on themselves, I’ve decided to make an exception.
Researchers exposed cell samples, both donated from human lungs and lab-grown, to vapour from e-cigarettes at a level designed to mimic occasional use.
They found that vaping caused damage to blood vessels and airways in the lungs due to a normal cell recycling process being disturbed.
To test the longer-term impacts, the researchers then turned to hamsters.
The rodents were exposed to vapour for five days in a row, once each day, before being left alone for 10 days and then examined.
On day 15, the researchers found increased levels of a protein called p62, which builds up when the clean-up process for damaged cells gets disrupted — the same pathway observed in the human cells.
Again, damage was seen in both blood vessels and airways, and individual cells were still dying 10 days after the last exposure.
A later experiment infected a group of hamsters with SARS-CoV-2, the virus that causes COVID-19 (remember COVID-19, anyone?) then exposed some to vapour.
Animals that had been exposed to five days of vapour carried significantly more SARS-CoV-2 than unexposed animals, probably due to genetic alterations in the genes involved in fighting infections.
So, exposure to moderate levels of vapour (by human standards) resulted in lung cell death, including for up to 10 days after the last exposure in hamsters, and a reduced ability to fight viral infections.
Let me repeat the usual caveats: this data can’t tell us exactly how vaping affects human lungs in healthy adults, teenagers, or someone with a chronic illness.
Nevertheless, the “circumstantial” evidence is mounting up. So, here’s my advice
1️⃣ If you’re a smoker and vaping helps you reduce the number of cigarettes you get through, that’s a good thing.
2️⃣ However, vaping is not harmless, so it should only be used as a temporary measure.
3️⃣ If you don’t smoke, but you’re thinking about vaping, please don’t. All you’re doing is trading your hard-earned cash for a nicotine delivery system. Remember, all the major tobacco companies either own or have invested in vape companies. You’ll still be giving them your money.
4️⃣ Much of the advice for stopping smoking can be useful for anyone who wants to stop vaping. There’s some excellent advice here.
Gut health
📈 3 Things More Important Than 30g Of Fiber
These days, gut health specialists recognise that the distinction between soluble and insoluble fibre, though accurate, is insufficient.
Here are three other criteria you should bear in mind when choosing your fibre
1. Viscosity
This refers to how thick or gel-like the fibre becomes when mixed with water.
Psyllium and beta-glucan from oats are highly viscous, whereas wheat bran is much less so.
Why does it matter?
Higher viscosity can be important for anyone who wants to reduce LDL cholesterol, moderate blood sugar spikes (e.g. people with type 2 diabetes) or regulate bowel movements (whether constipation or diarrhoea is the issue). Just make sure you drink plenty of water if you're taking fibre to relieve constipation.
2. Fermentability
This is about how easily gut microbes break fibre down. A by-product of this process is the production of short-chain fatty acids, which have beneficial effects throughout the body.
Fast-fermenting fibres include inulin (found in chicory root), fructooligosaccharides (FOS) and galactooligosaccharides (GOS), found in foods such as garlic, onions and legumes.
Medium-fermenting fibres include RG1s from carrot and beta-glucan from oats.
Slow-fermenting fibres include some types of resistant starch and fibers found in beans, nuts, seeds (and even day-old rice!)
Why does it matter?
The speed at which fiber ferments determines which gut microbes it will feed. Eating too much of one may mean limiting what’s available for bacteria in other parts of the gut. As different gut bacteria produce different short-chain fatty acids, you really need to feed the whole length of your gut.
3. Water-Holding Capacity
As the name suggests, this refers to how much water fiber can hold.
Why does it matter?
It's all about regulating stool consistency. Water retention can help improve stool consistency and may relieve constipation or diarrhoea symptoms, depending on the fibre and the individual. Flaxseeds and chia seeds all have good water-holding properties.
Even then, things aren't as clear-cut as these 3 neat categories would suggest.
Take chia seeds as an example: their structure contains both gel-forming soluble fibre and insoluble structural fibre, which means different parts of chia seeds have different fermentation rates.
To be honest, you could go crazy trying to tick all these boxes. Your safest bet for getting a variety of fibre types is to eat a varied diet that includes 30 different plant foods (including nuts and seeds) each week.
Or…you could always try LOAM: a six-in-one mixture of slow-, medium- and fast-fermenting fibres that delivers 10 g of the good stuff in a single serving. Stir it seamlessly into your morning coffee; you won't notice a thing.
REFLECTIONS
🧠 How To Take a Dump (For Your Brain)
Ever go to bed realising you not only have the same list of things to do rattling around your mind, but that it’s actually grown during the day and…wait, what did my wife ask me to buy from the chemist??
There are plenty of people online telling you to get all these thoughts out of your head and on to paper aka a brain dump and that’s sensible advice. It’s worth doing just to get rid of the mental burden.
But I’ve realised recently this isn’t enough.
Because “buy nappies for the little one” and “is it worth investing another six-figure sum into product development for LOAM?" don't really belong on the same list.
Here’s how I do a brain dump now.
1️⃣ Divide a piece of paper into four and label each box: To-do, Decisions, Ideas, Let go.
2️⃣ To-do: Populate this box with all the little decisions you need to make and actions you need to take. Pay that invoice, make that appointment etc.
3️⃣ Decisions: These take more time. Whatever decision you need to make will require some amount of mental effort, so pick a time when you can devote the necessary time to tackling these decisions.
4️⃣ Ideas: Anything you’re thinking about goes here. We have lots of ideas, and now is not the time to worry about how realistic they are. Get them down and choose one to pursue when you get the chance.
5️⃣ Let go: By far the most important, in my opinion. Here, you put down the argument you had with your partner, the mistake you made five years ago, the witty retort you couldn’t think of in time, or the embarrassing thing you said in real life or online.
Now cross each one out and remind yourself they don’t belong anywhere — not in your mind, nor on that piece of paper.
One last tip: do it on paper, not on your phone. Nothing compares to physically crossing out a completed task on your to-do list or crossing out something taking up mental space that doesn’t deserve to be there.
👋 Who are you again? I’m Karan Rajan - a doctor and curious explorer of all things health and wellness. I'm the founder of LOAM Science, a microbiome company aiming to create the best fiber product in the world! I host the Dr Karan Explores Podcast, where I talk to experts in science and medicine to cut through the BS of modern health advice. If you'd like an easy way to dig through the archive, you can ask me any questions about the podcast and talk to my digital librarian here. I've also written two books "This Book May Save Your Life" and "This Is Vital Information".
If you feel strongly about some health things or just want to say hi? Hit reply... I’d love to hear it and hear from you! (yes I read every reply!!!)f
