Diet & Nutrition

Electrolytes on GLP-1: The Sodium, Potassium, and Magnesium Triangle

April 8, 2026 · 4 min read · By the Sharpy team
TL;DR

Aim for 2,000–3,000 mg sodium, 3,000–4,000 mg potassium, and 300–400 mg magnesium daily on a GLP-1. Salt your food, eat potassium-rich foods (bananas, potatoes, leafy greens), and supplement magnesium glycinate at night for sleep, constipation, and muscle cramps.

If you're on a GLP-1 and you have leg cramps at night, headaches, dizziness when you stand, or constant low energy, the culprit is usually electrolytes — specifically sodium, potassium, and magnesium. All three are commonly low because food intake is down and sweating + GI losses are up.

The daily targets

Sodium: 2,000–3,000 mg/day for most active adults; up to 4,000 mg if you're exercising hard or in heat.

Potassium: 3,000–4,000 mg/day. Most Americans eat <2,500 mg.

Magnesium: 300–400 mg/day for women; 400–500 mg for men.

(These are general targets for healthy adults without kidney disease or heart failure on potassium-restricting medications. Your prescriber can adjust if you have specific conditions.)

Why GLP-1 patients run low

Sodium: Most American sodium comes from processed food (bread, cheese, lunch meat, condiments, restaurant meals). When food intake drops 50%, sodium drops with it — often to 1,000–1,500 mg/day, which is below the threshold for symptomatic hyponatremia.

Potassium: Comes mostly from fruit, vegetables, beans, and dairy. Reduced food volume = reduced potassium. The ratio of sodium to potassium also matters; you want roughly 1:1 to 1:2.

Magnesium: Comes from leafy greens, nuts, seeds, whole grains. Most adults are already low; GLP-1 makes it worse. Diarrhea episodes accelerate loss.

Sodium

Don't be afraid of salt on a GLP-1. The "low sodium for everyone" advice was built on data from people eating processed food. If you're eating mostly whole foods and 50% less, you need to add salt deliberately.

Food sources:

  • A pinch of salt on every meal: ~500 mg total/day
  • Pickles, olives, capers: 200–400 mg per serving
  • Cured meats (in moderation): 500+ mg per serving
  • Broth (bone or chicken): 700–900 mg per cup

Supplement source:

  • Electrolyte mix with 500–1,000 mg sodium per serving (LMNT is the most concentrated; Liquid IV is moderate; Pedialyte is gentler)

Potassium

The high-potassium foods that are realistic on a GLP-1:

  • Banana (450 mg per medium)
  • Baked potato with skin (900 mg per medium)
  • Sweet potato (450 mg per medium)
  • Spinach, cooked (840 mg per cup)
  • Avocado (700 mg per fruit)
  • Greek yogurt (240 mg per cup)
  • Salmon (530 mg per 4 oz)
  • Beans (500–700 mg per cup)
  • Tomato sauce (700 mg per cup)
  • Cantaloupe (470 mg per cup)

Most patients can hit 3,000+ mg of potassium with a banana + a baked potato + a serving of greens or beans.

Supplement source: Potassium supplements are limited by the FDA to 99 mg per pill (for safety reasons — too much potassium can be cardiotoxic). "Lite salt" is a kitchen-friendly substitute that's about half potassium chloride. Most patients should get potassium from food, not pills.

Magnesium

The most chronically depleted of the three. Symptoms of low magnesium:

  • Muscle cramps, especially leg cramps at night
  • Difficulty falling asleep
  • Migraines
  • Anxiety
  • Constipation
  • Heart palpitations

Food sources:

  • Almonds, 1 oz (80 mg)
  • Cashews, 1 oz (75 mg)
  • Spinach, cooked, 1 cup (160 mg)
  • Pumpkin seeds, 1 oz (150 mg)
  • Black beans, 1 cup (120 mg)
  • Dark chocolate, 1 oz (65 mg)
  • Avocado (60 mg)

Supplement source:

  • Magnesium glycinate: Best-tolerated form. 200–400 mg before bed. Helps sleep and constipation.
  • Magnesium citrate: Stronger laxative effect. 200–400 mg. Useful if constipation is the main concern.
  • Magnesium oxide: Cheap but poorly absorbed. Skip.
  • Topical magnesium (sprays, oils): Marketing-driven. Stick with oral.

A practical electrolyte day on a GLP-1

Morning (on waking):

  • 16 oz water + LMNT or Liquid IV packet (~1,000 mg sodium, 200 mg potassium)

Breakfast:

  • Greek yogurt + banana (350 mg potassium, 80 mg magnesium)

Lunch:

  • Salmon + sweet potato + spinach (1,500 mg potassium, 200 mg magnesium, 600 mg sodium with salt)

Dinner:

  • Chicken + baked potato with skin + side salad with avocado (1,500 mg potassium, 100 mg magnesium, 500 mg sodium with salt)

Bedtime:

  • 200 mg magnesium glycinate

Total approx: 2,500 mg sodium, 3,500 mg potassium, 600 mg magnesium. On target.

When to call your doctor

  • Severe muscle cramps not responding to electrolytes
  • Heart palpitations or irregular heartbeat
  • Persistent dizziness with standing
  • Confusion or severe weakness
  • If you have kidney disease, heart failure, or take potassium-affecting medications (ACE inhibitors, ARBs, spironolactone), discuss your electrolyte intake with your prescriber before adjusting.

Bottom line

Sodium, potassium, and magnesium are the three electrolytes most GLP-1 patients run short on. Salt your food, eat potassium-rich foods (banana, potato, spinach, salmon), supplement magnesium glycinate at night. Most "I just feel terrible on this medication" complaints resolve within a week of fixing electrolytes.