How to Reduce Nighttime Urination | Dr. Andrew Huberman

Summary

The kidneys filter fluids most efficiently in the first 10 hours after waking due to circadian rhythms. To reduce nighttime urination: properly hydrate during the daytime so you aren't excessively thirsty at night, reduce fluid intake in the evening, and sip fluids slowly after 10 hours of waking rather than gulping. This allows the body's filtration system to process fluids more slowly so less ends up in the bladder overnight.

Takeaways

• 😀 You need about 8 oz or 240 ml of fluid per hour for the first 10 hours after waking to stay hydrated
• 😕 Your kidneys filter fluids most efficiently in the first 10 hours after waking
• 🤔 Circadian clock genes regulate kidney function over 24 hours
• 😊 Drink fluids at whatever rate feels comfortable during the day
• 🚰 Hydrate well during the daytime to reduce nighttime thirst and urine production
• 🌙 Reduce fluid intake 5-8 hours before bedtime to avoid waking up to urinate
• 🍵 Sip fluids slowly in the evening for slower absorption and less urine production
• 😴 Mechanosensors in your body respond to both the volume and rate of fluid intake
• 🤭 Gulping fluids speeds their passage into urine compared to sipping
• 💧 Consider waking up once or twice per night to urinate as totally normal

Q & A

Why is kidney function circadian dependent?

Kidney function is strongly regulated by circadian clock genes that impact whether the kidney will be highly active or have reduced function at different times of day.

What happens to kidney function 10 hours after waking?

At about 10 hours after waking, the kidney starts to significantly reduce its overall level of functioning and becomes less efficient at filtering fluids.

How can you avoid waking up to urinate at night?

Hydrate sufficiently during the daytime, reduce fluid intake at night, and sip any fluids slowly in the evening to avoid excessive nighttime urination.

Why does the rate you drink fluids impact urination?

The body's fluid filtration systems depend not just on fluid volume but on the rate it is ingested due to mechanosensors that signal more rapid excretion if fluids are gulped versus sipped.

What is the recommended evening fluid intake?

Ingest no more than 5-8 ounces of fluid in the evening by sipping slowly to reduce nighttime urination.

What happens if you gulp fluids versus sip them?

Gulping fluids signals the body to excrete those fluids more quickly compared to sipping them slowly.

What hormone regulates fluid retention and release?

The hormone vasopressin, also called antidiuretic hormone, regulates whether the body will retain fluid or release more urine depending on factors like salt levels and hydration status.

What are circadian clock genes?

Circadian clock genes are expressed in cells throughout the body and regulate organ functioning on a 24 hour circadian rhythm, being most active at certain times of day.

What is the purpose of kidney filtration?

The kidneys filter fluids in the body to remove contaminants and regulate fluid and electrolyte balance through mechanisms like hormone release and urination.

What other organs have circadian dependent functioning?

In addition to the kidneys, circadian clock genes impact functioning of organs like the gut which follows a 24 hour cycle.