Quick answer

Women need 2,600 mg of potassium and 310 to 320 mg of magnesium a day, less than men, and share the same sodium ceiling of under 2,300 mg. Pregnancy raises potassium to 2,900 mg and magnesium to 350 to 360 mg. Women usually lose less sweat than men, mainly because they tend to be smaller.^1,2,3,4

Key facts

Adult women average about 2,320 mg of potassium a day from food, below the 2,600 mg recommended.⁵
Breastfeeding women need about 2,800 mg of potassium a day.¹
Each liter of sweat is about as salty in women as in men.⁴
Chloride needs fall from 2.3 g a day to 2.0 g after age 50 and 1.8 g after 70, for women and men alike.⁶

How much women need

Daily amounts for women, from food, drink and supplements together^5,6,7
Mineral	Ages 19 to 50	51 and older	Pregnancy	Breastfeeding
Potassium	2,600 mg	2,600 mg	2,900 mg	2,800 mg
Magnesium	310 mg to age 30, then 320 mg	320 mg	350 to 360 mg	310 to 320 mg
Chloride	2.3 g	2.0 g to age 70, then 1.8 g	2.3 g	2.3 g

Sodium runs the other way: its figure is a ceiling, not a target, and the Daily Value of less than 2,300 mg is the same for women and men.³

Food leaves many women short of potassium. Adult women average about 2,320 mg a day from food against 2,600 mg recommended, which is why fruit, vegetables, beans and dairy do more for that gap than any drink mix, most of which carry 99 mg or less per serving.⁵

Women over 40, 50 and 60

Potassium needs do not change with age for women, and neither does the sodium ceiling. Magnesium edges up from 310 mg a day before 31 to 320 mg from 31 on, while chloride drops to 2.0 g after 50 and 1.8 g after 70.^5,6,7

Sweat rates tend to be lower in older adults, mostly because fitness declines rather than because of age itself.⁴

Some people lose their sense of thirst as they age, so they may not drink enough.⁸

MedlinePlus advises drinking enough water every day and asking a health care provider how much is right for you, which matters more with age than any particular mix.⁸

Sweat, body size and the menstrual cycle

Men tend to sweat more than women mainly because they are larger and produce more heat. Sweat sodium concentration does not differ much between adult men and women, or with age.⁴

Whole-body sweat losses do not differ much across the menstrual cycle, and a review of rehydration studies found no special concerns for women linked to cycle hormones.^4,9

In practice, a smaller woman doing the same session as a larger man will usually lose less fluid and less sodium in total, even though each liter of her sweat is just as salty. Sweat rates differ so much from one person to the next that weighing yourself before and after training tells you more than any average.^4,10

What the evidence shows for women

Sweat research leans male. In the sweat testing data Baker reviewed, about four in five of the 506 athletes were men, so the averages behind the sodium guidance come mostly from them.⁴

Sodium replaces what is lost in sweat and helps the body hold on to fluid after long or heavy-sweat exercise*^4,11,12,13

Moderate evidence

Sodium's role in fluid balance is well established. Sports nutrition guidance suggests taking sodium mainly for exercise longer than about 2 hours, for heavy or salty sweaters, or in heat, at about 300 to 600 mg an hour; one scoop is roughly the sodium in a liter of average sweat. A modelling study found sodium replacement unnecessary in realistic scenarios for a soccer match or a marathon, so for shorter sessions it is likely a matter of taste, not need.

Amount studied: About 300 to 600 mg of sodium an hour during exercise lasting more than about 2 hours, in heat or with heavy sweating

We found no research showing that women need a different electrolyte formula from men. The rehydration studies we read found no special concerns tied to the menstrual cycle.⁹

What's in ours

What’s in ours

Creatine + Electrolytes: Sodium, 1,000 mg per serving, from the label

For a woman, a scoop's 1,000 mg of sodium is the same 43% of the Daily Value as for a man, while its 200 mg of potassium is about 8% of her 2,600 mg daily need.^1,3

Pregnancy, low blood sodium and who should ask first

In the 2002 Boston Marathon study, women were more likely than men to finish with low blood sodium in a simple comparison, but not once weight gain during the race, finishing time and body mass index were taken into account. Gaining weight during the race, a sign of drinking more than was sweated, was the stronger warning sign.^14,15

Ask your doctor before using an electrolyte product if you are pregnant or breastfeeding
Ask first if you have high blood pressure, kidney disease or a heart condition
Ask first if you take a water pill, a blood pressure medicine or lithium
If you take spironolactone, its label advises avoiding potassium supplements and salt substitutes that contain potassium¹⁶

MedlinePlus notes that people over 50 are among those more sensitive to salt, so women past 50 who are thinking about a daily high-sodium drink should raise it with their doctor.¹⁷

Questions people ask

Do women need electrolytes more than men?

Not as a rule. Women need less potassium and magnesium than men, the sodium ceiling is the same, and women usually lose less sweat in total because they tend to be smaller. Needs rise in pregnancy and while breastfeeding.^1,2,4

Do I need more electrolytes at certain times of my cycle?

Not according to the studies we read. Whole-body sweat losses change little across the menstrual cycle, and a review of rehydration research found no special concerns tied to cycle hormones.^4,9

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Sources

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.