Dizziness & Lightheadedness

Symptoms & Logged Metrics · Reviewed August 2026

Definition

Dizziness and lightheadedness cover a group of sensations, from feeling faint to a spinning feeling in the room, most often reflecting a temporary change in blood flow or balance signals to the brain.[1] It's one of the most common symptoms in medicine, affecting an estimated 15 to 20 percent of adults each year.[1]

Educational content, not medical advice. For personal or fertility concerns, please consult your doctor.

What Dizziness Is

Dizziness is a catch-all term, and it's typically sorted into four rough categories: vertigo (a spinning sensation tied to inner-ear or balance-system dysfunction), presyncope (a near-fainting feeling tied to reduced blood flow to the brain), lightheadedness, and disequilibrium, or unsteadiness on your feet.[1] The categories overlap in practice, people often have trouble describing exactly which one they're feeling, and a single episode can shift from one to another.[1] It shows up in women up to three times as often as in men, and it gets more common with age.[1]

How It's Logged

There's no wearable sensor or lab value for dizziness. It's a logged symptom: you record that an episode happened, roughly how intense it felt, and when, which turns something easy to forget by the end of the day into a pattern you can look back on.

Why People Track Dizziness

Pregnancy is one of the most common contexts for new dizziness. Blood pressure typically falls during the first half of pregnancy as vessels relax and widen, reaching its lowest point around 24 weeks before gradually climbing back toward baseline, while plasma volume expands by 45 to 55 percent to support the growing blood supply.[2] Those two shifts together are a big part of why lightheadedness, especially on standing, is such a well-documented early and mid-pregnancy symptom. For more on early pregnancy signs, see our guide to early pregnancy signs.

Because dizziness so often traces back to blood pressure and fluid balance, people log it alongside blood pressure readings, heart rate, and how much water they've had that day. A log that pairs dizzy spells with those numbers turns a vague "I keep feeling off" into a pattern with actual shape to it.

How Go Go Gaia Tracks Dizziness

Go Go Gaia logs dizziness with a 1-click entry: rate how often or how intense episodes felt that day, no typing required. Each entry is charted against your cycle phase and everything else you track, from blood pressure and heart rate to hydration and sleep, so you can see how dizzy spells line up with the rest of your data.

Log dizziness in one tap

Track dizziness alongside your blood pressure, heart rate, and cycle in Go Go Gaia.

Download on the App Store

Free to log. No account needed to start.

What the Research Shows

Blood volume plays a direct, measurable role. In a controlled study, healthy adults who drank 500 mL of water 15 minutes before a standing-tolerance test lasted an average of 5 minutes longer before feeling faint than when they drank a small control amount, showing how sensitive orthostatic tolerance is to fluid status.[6]

Whether dizziness itself shifts across the menstrual cycle is less settled. One study of healthy women found no difference in orthostatic tolerance, how well blood pressure holds up when standing, across cycle phases.[3] But a separate study in women with postural orthostatic tachycardia syndrome (POTS) found more presyncope episodes in the early follicular phase, when estrogen and progesterone are both low, than in the mid-luteal phase, when both hormones are elevated and support greater fluid retention.[4] More broadly, estrogen and progesterone help set the body's baseline for fluid regulation, including how much plasma volume it holds onto, which is part of why hydration needs can shift across the cycle.[5]

Related Terms

Blood Pressure

The force of blood against artery walls, and the metric most directly tied to feeling lightheaded on standing.

Heart Rate

Beats per minute, often logged alongside dizziness to see how the two track together.

Heart Palpitations

The feeling of a pounding or fluttering heartbeat, a common companion symptom to dizzy spells.

Fatigue

Tiredness that doesn't fully lift with rest, frequently logged on the same days as dizziness.

Nausea

The queasy-stomach sensation that often shows up alongside dizziness, sharing some of the same brain circuitry.

Frequently Asked Questions

Educational information based on published sources. Not medical advice. For personal concerns, please consult your doctor.

Is it normal to feel dizzy during pregnancy?

Feeling lightheaded, especially when standing up, is a well-documented pregnancy symptom. Blood pressure typically drops in the first half of pregnancy, reaching its lowest point around 24 weeks, while plasma volume expands by 45 to 55 percent to support the growing blood supply.[2]

Does dizziness change across the menstrual cycle?

The evidence is mixed. One study found no difference in how well blood pressure holds up when standing across cycle phases in healthy women,[3] while a separate study in women with postural orthostatic tachycardia syndrome found more near-fainting episodes in the low-hormone early follicular phase than in the high-hormone mid-luteal phase.[4]

How is hydration linked to feeling lightheaded?

Reduced blood volume, including from dehydration, makes it harder for blood pressure to hold steady when you stand up. In a controlled study, healthy adults who drank 500 mL of water measurably improved how long they could tolerate standing before feeling faint.[6]

References

  1. Davis AJ, Pozun A. Evaluation of the Dizzy and Unbalanced Patient. StatPearls [Internet]. NCBI Bookshelf. NBK589645
  2. Pascual ZN, Langaker MD. Physiology, Pregnancy. StatPearls [Internet]. NCBI Bookshelf. NBK559304
  3. Claydon VE, Younis NR, Hainsworth R. Phase of the menstrual cycle does not affect orthostatic tolerance in healthy women. Clinical Autonomic Research. 2006;16(2):98-104. doi.org/10.1007/s10286-006-0330-y
  4. Fu Q, VanGundy TB, Shibata S, Auchus RJ, Williams GH, Levine BD. Menstrual cycle affects renal-adrenal and hemodynamic responses during prolonged standing in the postural orthostatic tachycardia syndrome. Hypertension. 2010;56(1):82-90. PMC2894615
  5. Stachenfeld NS. Sex hormone effects on body fluid regulation. Exercise and Sport Sciences Reviews. 2008;36(3):152-159. PMID 18580296
  6. Schroeder C, Bush VE, Norcliffe LJ, et al. Water drinking acutely improves orthostatic tolerance in healthy subjects. Circulation. 2002;106(22):2806-2811. doi.org/10.1161/01.CIR.0000038921.64575.D0

Sourced from peer-reviewed research and, for basic mechanism claims, established references like NIH and StatPearls. Every citation above is checked to confirm it resolves to a real source and supports the sentence it's attached to. Last reviewed August 2026. See our full methodology on the Encyclopedia hub.