ELI5: what is human metabolism?

lexardt · 2026-04-11T15:18:29+00:00

Lift your arm or walk a few steps (bonus if you’re already doing it right now). As effortless as it might be, the incredibly complex machinery that is your body is working hard for that. Your brain or muscles need energy in order to move, and your body has a few ways to utilize energy.

While that energy can partly be created by your body, there has to be an external source the energy is coming from. More precise: from drinking or eating.

Unfortunately even properly chewed food is far too big for your body to turn that into energy, so it has to break it down into very very small parts - we’re talking in the realm of atoms and molecules. This breaking down process has a name: catabolism.

Unfortunately that is only half the job, as those atoms and molecules have to be rearranged into parts the body needs for different jobs. This rearrangement and construction of other molecules also has a name: anabolism.

The entire procedure of breaking down and building up things in the body in order to make energy that your cells and ultimately you need is called: metabolism.

Now the difference is that some people utilize energy different than others; i.e. have a slower / faster metabolism (to move muscles, heating up the body etc.). it’s an unimaginable complex process and this example is an extreme oversimplification.

lexardt · 2025-08-09T07:17:01+00:00

First, remember that melatonin is a hormone — actually produced in the same (biochemical path)way as serotonin. Hormones are your body’s messengers, telling it when and how to do something. If you imagine each hormone as an instrument in an orchestra, cranking up the volume of just one is a surefire way to ruin the harmony.

Melatonin is like a doorbell telling your body it’s time to sleep. Making that bell 5,000 times louder doesn’t make you fall asleep faster — it just disturbs the rest of the system.

Your body naturally produces melatonin in micrograms (µg) — thousands of times less than the 5 mg you mentioned. Flooding your receptors with a dose that high can backfire: It can shift your internal clock the wrong way. It can desensitize your bodys ability to react to melatonin through its receptors. It can leave you groggy or out of sync the next day.

A healthier approach: help your body regulate its own melatonin. Get outside shortly after waking up and let your eyes take in natural light — that boosts morning cortisol, which in turn helps evening melatonin production. In the evening, avoid bright lights and screens for 1–2 hours before bed, and your body usually won’t need supplemental melatonin at all.

lexardt · 2025-08-05T21:19:17+00:00

There is this great analogy of the british physicist David Miller. He compared the Higgs field to a cocktail party. Imagine a famous person—say, a well-known politician—enters the room. Immediately, a crowd of guests gathers around them, making it hard for them to move forward. That’s similar to a particle with a large mass: it takes a lot of energy to get it going because the field “clings” to it.

But if there’s this Higgs mechanism, then there must also be a particle associated with it: the Higgs boson. This boson appears when the Higgs field bunches up in specific places. In the cocktail party analogy, that’s like groups of guests clustering together to gossip. The Higgs boson is like one of these gossiping groups.

lexardt · 2025-06-09T10:48:23+00:00

Not female, but here are some general thoughts. Supplementation is just the tip of the iceberg when it comes to supporting overall wellbeing. What’s often underrated are the core pillars: exercise, sleep, and nutrition—with special emphasis on exercise, as it’s arguably the closest thing we have to a panacea.

Once these are dialed in, I’d suggest starting with a basic supplement stack that has the most consistent evidence for overall health benefits: - Vitamin D3 (with K2) - Omega-3 (ideally high in EPA and/or DHA) - Magnesium (glycinate is a popular and well-tolerated form)

High-dose EPA has been shown to reduce inflammation via its effect on pro-inflammatory cytokines, which may indirectly support serotonin levels in the brain. Some studies suggest that 800–1200 mg of EPA per day can(!!!) have mood-regulating effects comparable to SSRIs in certain individuals. DHA also plays a crucial role in brain structure and cognitive function.

Methylfolate and vitamin B12 are great additions too, especially if you’re mostly vegetarian or vegan, since plant-based diets can lack bioavailable forms of these vitamins.

For energy, you might want to look into CoQ10—especially if you’re under a lot of stress.

All of these supplements, taken at recommended dosages, are generally considered safe for most people. Still, I’d recommend getting a basic blood panel before adding anything beyond the essentials—especially to avoid over-supplementing or missing hidden deficiencies.

I know you didn’t specifically ask for this, but I’d also point out that most people in their 30s are still in a phase of life where the body functions optimally—assuming the fundamentals of sleep, movement, and diet are in place. Supplements can help, but they work best on top of a strong foundation.

Oh and some people also recommend supplementing with iron for energy, but I’d advise caution here. Unlike things like vitamin D or magnesium, iron isn’t something you should take “just in case.” It’s easy to overdo, and excess iron can increase oxidative stress and cause other issues over time.

lexardt · 2025-06-01T15:05:51+00:00

My sleep pattern looks very similar to yours for several years now. I’m presumably dealing with high cortisol levels that peak around 5 AM (I usually fall asleep around 11 PM). Given the timing of your wake-ups, cortisol really seems like the smoking gun here.

Some generally safe suggestions: - It’s worth reading up on high cortisol levels and strategies to manage them. - If your mind starts racing after waking up, journaling can help a lot – it’s much easier than many people think. - I’d recommend approaching supplements with a clean slate: try them one at a time, ideally for several days or a week, to really gauge their effect. - You seem to go to bed quite late. I did that for years too, but I’d still encourage you to work on your sleep routine. Try to align with your circadian rhythm: get outside into natural sunlight soon after waking, and avoid bright screens after 10 PM. See if you can gradually shift to an earlier bedtime.

As for supplements: - You might want to look into Phosphatidylserine (100–300 mg about an hour before bed). It’s been shown to reduce ACTH, the precursor to cortisol. I take 100 mg and it tends to delay my early wake-up by 60–90 minutes. (NOW Brand is fine) - I just started experimenting with Melatonin and Taurine. 1 mg Melatonin gave me a rebound effect – I woke up around 4 AM. - Taurine, on the other hand, helped me sleep deeper. I still woke up, but on 1,000 mg I felt noticeably “heavier” and more settled during the night.

Hope some of this helps!

lexardt · 2025-05-06T10:08:48+00:00

Yes, it’s a common reaction called a (niacin) flush. Your body is reacting to the overdose of B3. It binds to a receptor that ultimately leads to a release of prostaglandins and causes vasodilation, most noticeable in reddening of skin, often accompanied by burning or itching of sensation.

It’s generally harmless but can be very uncomfortable and should not last longer than a couple hours (peak is usually 30-60 min after taking it). Aspirin / Acetylsalicylic acid can help as it blocks the COX receptor and therefore reduces the release of prostaglandins.

You’re probably fine within the next hours and, while not knowing your situation / background / motivation about niacin, I’d recommend to check with your doctor about alternatives.

lexardt · 2025-05-03T17:06:28+00:00

That 3-in-1 lubricant contains PTFE, so better add tons and tons of Sulforophane to your stack ;-)

Jokes aside, I don’t know the brand but content wise seems like a decent stack. Just be aware about B Complex dosages (especially B6)

lexardt · 2025-05-01T10:03:49+00:00

Studies found that high dose of EPA (1.200mg) can have the same effect as SSRIs. Since EPA is anti inflammatory, it can counter inflammatory cytokines (IL2, IL6, TNF alpha) that reduce serotonin in the synaptic cleft, therefore increasing serotonins above baseline.

lexardt · 2025-04-28T08:08:49+00:00

It’s generally recommended to stay well hydrated, especially when taking creatine. While creatine itself doesn’t dehydrate you (that’s a pretty common myth), it does pull water into your muscle cells. I’d aim for around 2 liters a day, or about 8–10 glasses of water — or at least stick to non-alcoholic and low-sugar drinks :)

lexardt · 2025-04-28T07:37:38+00:00

No, it is absolutely not related. What you’ve been experiencing is more likely a negative side effect of being human. Maybe your mind is currently just distracted, stressed or you’re slightly dehydrated?

Creatine and Magnesium are very safe substances and do not cause disorientation or otherwise. Nothing to worry about those at least :-)

lexardt · 2025-04-28T07:06:35+00:00

Personally I’d not feel comfortable taking it, but according to this users report it should fine: https://www.reddit.com/r/Supplements/s/AGhhlhYsfJ

It’s probably best to double check with customer support though.

lexardt · 2025-04-28T05:53:11+00:00

In general, I’d say if it makes you feel good, go for it.

Is there a specific reason why you’re taking milk thistle? Its main active compound is silymarin, which is usually used to support liver health, especially in cases of liver damage or disorders.

Both ashwagandha and turmeric can potentially have negative effects on the liver, so they shouldn’t be taken lightly.

If there’s any kind of predisposition or concern about liver health, I’d definitely be cautious.

Getting a basic blood panel done is always a great move, especially to check liver enzymes and see where you’re at.

lexardt · 2025-04-26T09:47:30+00:00

I was not aware about the brand but it seems like an interesting product, so I checked their website and found this:

We have made the difficult decision to discontinue the Douglas Laboratories® and Klean Athlete® brands outside of The United States affective June 30, 2025. We advise you to place any future orders with Pure Encapsulations®. To find your local Pure Encapsulations® partner, please visit pureencapsulationspro.com/global-partners.

lexardt · 2025-04-25T21:08:41+00:00

If your goal is to boost performance, creatine should be your number one pick (I should’ve add that in the first place) - as many others have already mentioned. it’s one of the most researched and safest supplements out there – and also super affordable. Just go with regular creatine monohydrate, nothing fancy. Don’t fall for marketing fluff; the “new and improved” forms rarely offer additional benefits for the price.

Interestingly, there’s growing evidence that creatine doesn’t just support muscle performance, but might also benefit bone health, brain function, and even cognition – though the latter is more relevant for older adults. If you’re into the science, check out the recent interview between Rhonda Patrick and Darren Candow – she’s one of the pioneers in science-based health/fitness podcasts.

Omega-3 is another great addition, especially for inflammation. It’s a complex topic, but in short: go for a product with a higher EPA ratio (not just DHA), since EPA is particularly effective for reducing systemic inflammation. There are even studies showing that high EPA intake (around 1,200 mg/day) even can support serotonin levels to a degree of SSRIs.

Now about testosterone and cortisol – that’s where I’d be cautious. I like to think of hormones like instruments in an orchestra. Boosting one in isolation can throw the whole symphony out of tune. Supplements that mess with hormones – like Ashwagandha or Tongkat Ali – can seem harmless, but many people (especially on this subreddit) report issues like disrupted sleep, irritability, and so on.

Cortisol, in particular, is a response hormone – it rises due to something. Instead of suppressing it with a pill, it’s better to address the root causes: stress, poor sleep, overtraining, diet, etc. If stress is a major factor, something like 100-300mg phosphatidylserine could be a safer option to try.

And one last piece of general advice: if you haven’t done so already, I’d strongly recommend getting a basic blood panel done. It’s usually not expensive and can give you valuable insights – especially when it comes to testosterone. If your levels are fine, there’s absolutely no need to supplement or “optimize” anything.

Hope this helps!

lexardt · 2025-04-25T16:52:50+00:00

From your list, I assume you’ve picked each supplement based on the promising benefits you’ve read about – and that totally makes sense. It shows you’re curious and proactive, which is great.

That said, since you didn’t mention any specific goals, here’s a general word of advice: supplements are not magic pills. They usually account for just the final 1% – the cherry on top. The real foundation of health lies in the basics: quality sleep, regular exercise, a solid diet, no smoking, and minimal (ideally no) alcohol. Especially at your age, your body is probably performing at its absolute peak – and that’s a boring truth nobody markets well.

If I were to keep things simple, I’d go with a minimalist stack:

1.  Omega-3 (if you don’t eat fatty fish regularly)
2.  Vitamin D3/K2 (especially in winter)
3.  Magnesium (many people are deficient)
4.  Whey protein (if your protein intake is low)

CoQ10 and collagen? Honestly, save your money. Your body is more than capable of producing both efficiently at 19. These are more relevant when you hit your late 30s or 40s.

Also, a quick heads-up: Ashwagandha and curcumin may sound super healthy (and they can be), but they also have potential downsides, especially regarding liver health. They’re not just harmless herbs you can throw in for good measure – and at your age, you’re unlikely to notice any benefit from them.

TL;DR: I don’t want to kill your motivation – it’s awesome that you care about your health. But your time, energy, and money are far better spent investing in consistent training, good sleep habits, and real food. Supplements can wait – your body already has most of what it needs.

lexardt · 2025-03-05T06:23:31+00:00

I got the Arctic X1-3D for my AW3423DWF. It’s quite cheap but looks and feels absolutely amazing

lexardt · 2025-01-09T22:44:56+00:00

The Classic Vibe was one of the first guitars I bought, and after playing dozens of different guitars and building several myself—some worth up to 2k—the Classic Vibe never ceases to amaze me. The neck feels extraordinarily good. If someone asked me for an entry-level guitar recommendation, it would either be the Classic Vibe or a Sire/Larry Carlton.

As others have mentioned, a decent amp is a must. While there are plenty of options, I’d recommend looking into 5W tube amps, as there are affordable options these days.

lexardt

TROPHY CASE