How to Reduce Nighttime Urination | Dr. Andrew Huberman
00:00:00.000 | [silence]
00:00:02.400 | You need about eight ounces or 240 milliliters of fluid
00:00:06.240 | per hour for the first 10 hours of your day after waking.
00:00:10.560 | Now, why did I say for the first 10 hours?
00:00:12.160 | Well, it turns out that the filtration of fluids
00:00:14.720 | from your body, which is accomplished, of course,
00:00:17.500 | by your kidneys and by way of your bladder
00:00:20.760 | and the excretion of fluid out urethra,
00:00:23.420 | so-called urination,
00:00:24.920 | is strongly, strongly circadian dependent,
00:00:28.360 | meaning the cells of your kidney
00:00:30.960 | and the cells even of your gut,
00:00:32.720 | in fact, all the cells of your body,
00:00:34.000 | but especially the cells of your kidney,
00:00:35.980 | which filter the fluid that comes into your body
00:00:38.840 | and that makes certain hormones like vasopressin,
00:00:41.520 | which is anti-diuretic hormone,
00:00:43.800 | all of that functioning of the kidney
00:00:46.040 | is under strong regulation
00:00:48.000 | by so-called circadian clock genes.
00:00:50.200 | Circadian clock genes are genes
00:00:51.400 | that are expressed in every cell,
00:00:53.140 | but that in certain cells of the body
00:00:55.200 | very strongly impact whether or not that organ,
00:00:57.920 | in this case, the kidney,
00:00:59.080 | is going to be activated, meaning functioning,
00:01:02.600 | at a very high level or at a reduced level.
00:01:05.760 | And we can make all of this very simple
00:01:07.360 | by simply stating what's contained in this beautiful review
00:01:10.360 | that I'll provide a link to if you want to learn more
00:01:12.040 | called "Circadian Rhythms in the Kidney."
00:01:14.440 | And basically what is known
00:01:16.360 | is that for the first 10 hours after waking,
00:01:18.260 | your kidney is filtering fluid within your body
00:01:20.880 | at a very rapid rate.
00:01:22.440 | There are a number of different cell types that do that,
00:01:24.680 | but they are basically taking that fluid,
00:01:26.880 | pulling out any contaminants,
00:01:29.520 | using hormones such as anti-diuretic hormone, vasopressin,
00:01:32.920 | to adjust whether or not you're going to hold onto fluid
00:01:35.280 | or release more fluid from your body in the form of urine,
00:01:37.560 | depending on the salt concentration,
00:01:40.000 | depending on how much fluid you need,
00:01:42.920 | your work output, the conditions you're in, all of that.
00:01:46.120 | However, at about 10 hours after waking,
00:01:50.280 | your kidney really starts to reduce
00:01:52.600 | its overall level of functioning.
00:01:54.120 | Now, that doesn't mean that your kidney
00:01:55.640 | cannot filter fluid 11 or 12 or 16 hours after waking,
00:01:59.440 | but it becomes far less efficient at doing so.
00:02:01.920 | And thank goodness it does,
00:02:03.080 | because you do not want your kidney filtering fluid
00:02:06.480 | at the same rate at midnight,
00:02:10.120 | assuming you wake up at say 7 or 8 or 9 a.m.,
00:02:12.920 | that it was filtering fluid at 10 a.m.
00:02:17.700 | In fact, we can say that if you want to reduce
00:02:21.680 | your nighttime waking in order to urinate,
00:02:24.220 | which is a common, common question and concern
00:02:26.960 | that many people have,
00:02:27.800 | how can I avoid waking up in the middle of the night
00:02:29.440 | to urinate?
00:02:30.280 | And there I say, it's perfectly normal to wake up once,
00:02:33.480 | maybe twice each night to urinate.
00:02:35.400 | But if you want to reduce the number of times
00:02:37.940 | that you wake up in order to urinate across the night,
00:02:40.820 | maybe even make that number zero times,
00:02:43.440 | you will greatly benefit by doing three things.
00:02:46.480 | First of all, make sure that you're hydrating sufficiently
00:02:49.640 | during the daytime.
00:02:51.080 | That will ensure that you are not excessively thirsty
00:02:54.240 | in the evening and therefore consuming a lot more fluid.
00:02:57.520 | Second, and related to that first point,
00:03:00.720 | is that you do want to reduce your fluid intake at night,
00:03:03.920 | provided you hydrated sufficiently throughout the day.
00:03:07.640 | And believe it or not,
00:03:09.360 | the rate at which fluid moves from your gut
00:03:12.760 | and into the cells and tissues of your body,
00:03:14.760 | and then from your bladder into urine,
00:03:17.460 | is determined not just by the volume of fluid you ingest,
00:03:20.820 | but also the rate at which you ingest that fluid.
00:03:24.000 | And you might be thinking, that's crazy.
00:03:25.680 | That makes no sense at all, right?
00:03:27.200 | If I drink a ton of fluid slowly,
00:03:28.960 | doesn't it still mean that I'm going to urinate a ton?
00:03:31.840 | Yes and no.
00:03:33.080 | It also stands to reason that you might ask,
00:03:36.160 | if I ingest very little fluid, but I do it very fast,
00:03:39.800 | is it going to be the case
00:03:40.760 | that I'm going to urinate it out very quickly?
00:03:42.560 | Well, yes and no.
00:03:43.960 | The point is that the fluid filtration systems of your body
00:03:47.920 | that range from the gut to the bladder
00:03:49.600 | and include the kidney, of course,
00:03:51.300 | depend not just on the volume,
00:03:53.660 | but on the rate of fluid that you ingest.
00:03:56.860 | Because of those mechanosensors that we talked about earlier,
00:04:00.020 | if you gulp down a bunch of fluids,
00:04:02.500 | you are going to excrete those fluids more quickly
00:04:04.660 | than if you sip them slowly.
00:04:06.620 | Excuse me, sip them slowly.
00:04:08.620 | So here's what I recommend.
00:04:09.980 | Throughout the day when you're trying
00:04:11.180 | to get your adequate yield of water or other beverages,
00:04:16.060 | feel free to gulp that fluid or sip it.
00:04:19.880 | I'm a gulper, not a sipper,
00:04:22.680 | but many of you are going to be sippers, not gulpers.
00:04:25.520 | Consume fluid at the rate that feels right to you,
00:04:27.880 | but feel comfortable gulping that fluid.
00:04:29.540 | However, in the evening,
00:04:31.520 | if you are somebody who has challenges
00:04:33.000 | with waking up excessively in the middle of the night,
00:04:35.300 | reduce your fluid intake,
00:04:36.640 | provided you've hydrated properly throughout the day.
00:04:39.120 | And I suggest consuming no more than five,
00:04:42.280 | maybe eight ounces of fluid
00:04:44.560 | between the time of 10 hours after waking
00:04:46.940 | and when you go to sleep.
00:04:48.260 | Again, if you're very thirsty or you under hydrate
00:04:50.460 | or it's very hot, feel free to ingest more fluid, please.
00:04:54.380 | But most people will find
00:04:55.460 | that if they reduce their fluid intake
00:04:56.940 | to about five ounces or less of fluid
00:04:59.500 | in that later part of the day,
00:05:01.260 | after 10 hours of having woken up and before sleep,
00:05:05.580 | and they sip those beverages as opposed to gulping them,
00:05:08.880 | that they will have fewer bouts
00:05:11.380 | of waking up in the middle of the night
00:05:12.580 | to go to the restroom and ideally zero.
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