Recruiting

Potassium Intake

Sponsor:

Florida State University

Code:

NCT07649005

Conditions

Healthy Older Adults

Eligibility Criteria

Sex: All

Age: 55 - 70+

Healthy Volunteers: Accepted

Interventions

low sodium/low potassium diet

high sodium/low potassium diet

high sodium/high potassium diet

Study Details

Brief summary:

The goal of this clinical trial is to determine if a high potassium intake can counteract the harmful effects of excess sodium on endothelial function in older adults with no history of cardiometabolic disease. The main questions it aims to answer are:

1. Can a high potassium intake attenuate dietary sodium-induced endothelial dysfunction in older adults.
2. Do changes in endothelial function in response to alterations in sodium and potassium intake differ by sex.

Participants will participants will consume three controlled diets for 10 days each with a minimum 14-day washout between interventions. The order in which participants consume the diets will be randomized. The study diets will vary in sodium and potassium content. Measures of cardiovascular health (blood pressure, arterial stiffness, endothelial function) will be assessed at the end of each diet.

Conditions

Healthy Older Adults

Study ID

NCT07649005

Start date

Mar 24, 2026

Status verified date

Jun, 2026

Completion date

Jun 30, 2027

Anticipated

Primary completion date

Jun 30, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 55 - 70+

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Adults ages 55-75 years
  • At least one-year post-menopause (females)
  • Willing and able to attend laboratory visits

Exclusion Criteria:

  • BMI ≥35 kg/m2
  • Seated blood pressure >135/85 mmHg
  • Current diagnosis or history of cardiovascular disease, diabetes, renal disease, cancer, or major cardiovascular event (e.g. heart attack or stroke)
  • Taking exogenous hormones or hormone replacement therapy
  • Following a vegan or gluten free diet
  • Significant weight loss (>10% of body weight) in the last 6 months, or actively trying to lose weight
  • Current or recent use of a diuretic (within the past 6 months) (e.g. spironolactone, eplerenone)
  • Current or recent use of a potassium binding medication (within the past 6 months)
  • Current use of blood pressure lowering medications (e.g. ACE inhibitors, calcium channel blockers, diuretics, vasodilators, beta blockers, AngII receptor blockers)
  • Current or recent use of the medication trimethoprim
  • Elevated blood lipids (LDL cholesterol ≥190 mg/dL)
  • Elevated serum potassium level (>5.1 mmol/L)
  • Elevated BUN (>22 mg/dL)
  • Elevated creatinine (>1.2 mg/dL)
  • Low eGFR (<90 mL/min/1.73 m²)
  • Current or recent use of tobacco, nicotine, or illicit drugs
  • Radical hysterectomy or oophorectomy (females)

Study Design

Enrollment

30 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Prevention

Interventions and Outcome Measures

Arms

experimental: low Na/low K, high Na/low K, high Na/high K

Three 10-day controlled diets in randomized order, each varying in sodium and potassium content. There is a minimum 2-week washout between diets.

experimental: low Na/low K, high Na/high K, high Na/low K

Three 10-day controlled diets in randomized order, each varying in sodium and potassium content. There is a minimum 2-week washout between diets.

experimental: high Na/high K, low Na/low K, high Na/low K

Three 10-day controlled diets in randomized order, each varying in sodium and potassium content. There is a minimum 2-week washout between diets.

experimental: high Na/high K, high Na/low K, low Na/low K

Three 10-day controlled diets in randomized order, each varying in sodium and potassium content. There is a minimum 2-week washout between diets.

experimental: high Na/low K, low Na/low K, high Na/high K

Three 10-day controlled diets in randomized order, each varying in sodium and potassium content. There is a minimum 2-week washout between diets.

experimental: high Na/low K, high Na/high K, low Na/low K

Three 10-day controlled diets in randomized order, each varying in sodium and potassium content. There is a minimum 2-week washout between diets.

Interventions

low sodium/low potassium diet

On this intervention, participants will be given a diet that provides 2,000 mg Na/day and 2,000 mg K/day

high sodium/low potassium diet

On this intervention, participants will be given a diet that provides 4,700 mg Na/day and 2,000 mg K/day

high sodium/high potassium diet

On this intervention, participants will be given a diet that provides 4,700 mg Na/day and 4,700 mg K/day

Primary outcome measure

  • Endothelial function [ Time Frame: "Day 11" after each of the three 10-day dietary interventions ]
  • Blood pressure [ Time Frame: "Day 11" after each of the three 10-day dietary interventions ]
  • Arterial stiffness [ Time Frame: "Day 11" after each of the three 10-day dietary interventions ]

Central Contacts and Locations

Central contacts

Andrea Lobene

850-644-1829alobene@fsu.edu

FSU Ann's College

850-644-6685

Locations

Florida State University

Recruiting

Tallahassee, Florida, United States, 32306

Contacts

Andrea Lobene

850-644-1829alobene@fsu.edu

More Information

Sponsor

Florida State University

Last update posted

Jun 15, 2026

Last verified

Jun, 2026

Keywords

  • sodium
  • potassium
  • endothelial function
  • cardiovascular disease risk factors

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Florida State University on 2026-06-15.