My piss is currently bright yellow from B vitamins. Just wondering how my body knows how much to take and how much to excrete?
In: Biology
One of the reasons is mal-absorption. I began taking Betaine HCL to better digest food and it also helps break down my multivitamin which as many of us tend to forget actually contain grainy metals. Some brands chelate theirs so its better absorbed but most dont. If you see Oxide written by any of them , those are usually the cheapest way to produce and low quality and also very hard to digest. I def urinate out less bright yellow when my stomach acid strength is ideal.
Things that are clumped together like to spread out. Like if you blow air into a balloon and don’t tie it closed, the air will rush out because it doesn’t like being forced together with so much other air
Your kidneys use this strategy to filter things from your blood. If there are very few vitamins in your blood, the vitamins you have will be happy to stay there because it isn’t too crowded. If you take a bunch of vitamins and there starts to be too much of them, they will want to spread out. They spread out by going into your bladder and then coming out in your urine
In the simplest ELI5 terms, if you have too much of a vitamin in your blood it will want to leave. If you have low amounts in your blood it will be happy to stay
Imagine a kitchen sponge. When it gets a little wet, it absorbs water. When you fully submerge it, it absorbs some, but eventually stops absorbing because it’s already full, called Saturated. Under normal conditions, something can’t hold more than it’s saturation point. (There are exceptions but this is ELI5 so I’ll leave that to the comments)
Your cells are like sponges, sort of. They have cell walls that act like sponges, soaking up nutrients and oxygen and other things the blood cells carry to them, and when a cell is saturated, it stops absorbing. Any of these items that make it through your body all the way to your kidneys were the leftovers, the extra water in the tub, after all the cell sponges were full. Your kidneys take that material and dispose of it through urine, because your blood can only carry so much stuff, so if these are leftovers, they’re not in demand and would just get in the way of the in-demand nutrients if they were allowed to keep circling.
There’s no decision, no intention. The function of absorbing or not is entirely automatic, like a sponge absorbing a drop of water, or not.
Your body temporarily “stores” water-soluble vitamins (like B and C) in the bloodstream, and they just flow around and get used up as needed. But your body also has to keep removing waste products that are also in the blood, using your kidneys and liver. The body doesn’t really have a “filter” to keep the vitamins in while removing the waste. It all gets excreted together. Fortunately the vast majority of people in developed countries get plenty of vitamins from their diets and maintain healthy blood levels without supplements, and there’s not really any reason to take supplements unless your doctor recommends them. A lot of multivitamins will have like 300% of the daily recommended amount, which means you’ll be peeing out at least 2/3 of it. Probably more, because you’re likely getting those vitamins anyway through your food in a form that’s easier for your body to absorb.
As an aside: It’s important to note that supplements are NOT regulated by the FDA in the US, and manufacturers can put in basically whatever they want to. The FDA only evaluates the product after it has arrived on market, not before. And there are thousands of new products being released every year so the FDA can’t keep up. Most supplements have not been tested for ingredient accuracy, efficacy, or safety.
Latest Answers