Low bicarbonate (CO2) on your labs: metabolic acidosis in kidney disease
Dr. Joan J. Morales Lappot, MD3 min read · Leer en español
In briefOn a basic metabolic panel, the line labeled "CO2" or "bicarbonate" tells us about the acid balance of your blood. When kidneys are weaker, that number often drifts low.
What it means
Every day, normal metabolism makes acid, and healthy kidneys remove it while rebuilding bicarbonate, the body's main buffer. In chronic kidney disease the kidneys cannot keep up, so bicarbonate falls. This is called metabolic acidosis. A level persistently below about 22 is worth attention.
Why it matters
- It pulls calcium and buffer from bone, weakening it over time
- It breaks down muscle, which can make you weaker
- It may speed up the loss of kidney function
What helps
Diet comes first. Fruits and vegetables are "base-forming": they help neutralize acid, while large amounts of meat, cheese and processed food add acid. Shifting the plate toward plants can raise bicarbonate on its own, as long as your potassium allows it. If diet is not enough, sodium bicarbonate tablets (yes, the same chemical as baking soda) are a simple, inexpensive treatment. Please do not use kitchen baking soda on your own; the dose and the sodium need to be planned.