Blood bicarbonate levels are maintained primarily by your kidneys and lungs working together, and the normal range for adults falls between 22 and 26 mEq/L. If your levels are low, several strategies can help raise them, from dietary changes to supplementation to medical treatment, depending on the underlying cause and how far below normal you’ve dropped.
How Your Body Regulates Bicarbonate
Bicarbonate is your blood’s main chemical buffer. It neutralizes acids produced by normal metabolism, keeping your blood pH in the narrow range needed for oxygen delivery, enzyme function, and cellular chemistry. The system works through a simple chemical reaction: carbon dioxide combines with water to form carbonic acid, which then splits into bicarbonate and hydrogen ions. Your body constantly adjusts both sides of this equation.
Your lungs control the carbon dioxide side. Breathe faster and you blow off more CO2, which shifts the balance and can raise pH. Your kidneys handle the bicarbonate side directly. They reabsorb bicarbonate back into the blood when levels are low and excrete it in urine when levels are too high. This kidney response is slower, taking several hours to kick in, but it’s the more powerful long-term regulator. When bicarbonate drops below 22 mEq/L, it typically means either your kidneys aren’t reclaiming enough bicarbonate, your body is producing too much acid (from kidney disease, uncontrolled diabetes, severe diarrhea, or other conditions), or both.
Eat More Alkaline-Forming Foods
Every food you eat produces either a net acid or net alkaline load once your body metabolizes it. This is measured by something called the Potential Renal Acid Load, or PRAL score. Foods with negative PRAL scores reduce the acid burden on your kidneys, allowing them to retain more bicarbonate. Foods with positive scores (meat, grains, cheese) do the opposite.
The most powerfully alkaline-forming everyday foods are leafy greens and certain fruits. Spinach has a PRAL score of -14.0 per 100 grams, meaning it significantly reduces your body’s acid load. Other strong performers include raisins (-14.4), bananas (-5.5), sweet potatoes (-6.5), kale (-7.8), avocados (-8.2), and beets (-5.8). Dates are particularly alkaline at -13.6. Even carrots (-5.7), potatoes (-4.0), and celery (-5.2) contribute meaningfully.
Fruits across the board tend to be alkaline-forming despite tasting acidic. Oranges, lemons, grapefruits, and berries all carry negative PRAL scores because their organic acids are metabolized into bicarbonate. Drinking orange juice (-3.6), vegetable juice (-3.8), or coconut water (-5.1) can also help. On the flip side, reducing high-PRAL foods like processed meats, hard cheeses, and refined grains lowers the acid your kidneys need to clear, indirectly supporting bicarbonate retention.
Dietary changes alone won’t correct a serious bicarbonate deficiency, but for people with mildly low levels or chronic kidney disease where the kidneys struggle to keep up with acid production, shifting toward more vegetables, fruits, and fewer animal proteins can make a measurable difference over weeks and months.
Oral Sodium Bicarbonate Supplementation
Sodium bicarbonate, ordinary baking soda, is the most direct way to raise blood bicarbonate outside a hospital. It’s inexpensive and available over the counter. For people with chronic kidney disease or mild metabolic acidosis, doctors sometimes prescribe oral sodium bicarbonate tablets to keep levels in the normal range. The goal is typically to bring serum bicarbonate above 22 mEq/L.
If you’re considering this route, the dose matters enormously. Too little does nothing; too much pushes you into metabolic alkalosis, where bicarbonate climbs above 26 mEq/L. Symptoms of excess bicarbonate include nausea, vomiting, muscle twitching, numbness or tingling in the hands and face, confusion, and prolonged muscle spasms. Severe cases can cause irregular heart rhythms, dangerously low potassium, and even coma. This is why supplementation should be guided by blood tests, not guesswork.
The sodium content is another consideration. Each dose of sodium bicarbonate delivers a significant amount of sodium, which can raise blood pressure and cause fluid retention. People with heart failure, high blood pressure, or kidney disease need to account for this added sodium load carefully.
Potassium Citrate as an Alternative
Potassium citrate works similarly to sodium bicarbonate in raising blood alkalinity, but without the sodium load. Your body converts citrate into bicarbonate through normal metabolism. It’s commonly prescribed for kidney stone prevention, where keeping urine more alkaline prevents certain types of stones from forming. A typical prescription dose is 40 mEq per day, split into two doses. The trade-off is cost: potassium citrate is a prescription medication and significantly more expensive than baking soda, which is one reason researchers are actively comparing the two head to head.
Bicarbonate Loading for Athletic Performance
Athletes use sodium bicarbonate to buffer the lactic acid that builds up during high-intensity exercise. The extra bicarbonate in the blood helps neutralize acid as muscles produce it, delaying the burn and fatigue that force you to slow down. The Australian Institute of Sport classifies sodium bicarbonate as a proven performance supplement.
The standard protocol is 200 to 400 mg per kilogram of body weight, taken with a small carbohydrate-rich meal about 2 to 2.5 hours before exercise. For a 70 kg (154 lb) person, that works out to roughly 14 to 28 grams. At the higher end of that range, blood bicarbonate typically rises by 5 to 6 mmol/L above baseline, and this elevated buffering capacity lasts 3 to 4 hours. Taking it in capsule form spread out over the pre-exercise window, rather than all at once, reduces the gastrointestinal distress that is the most common side effect (bloating, nausea, diarrhea).
An alternative approach for competition involves a multi-day loading protocol: 500 mg per kilogram of body weight per day, divided into five even doses taken with meals and snacks, for up to five days before the event plus the day of competition. This builds up buffering capacity more gradually and can be easier on the stomach. Either way, athletes should trial their protocol during training well before race day to gauge their individual tolerance.
Breathing Patterns and CO2
Because bicarbonate and carbon dioxide exist in a chemical balance, your breathing rate directly affects the equation. Chronic hyperventilation, whether from anxiety, pain, or habit, blows off excess CO2 and initially raises blood pH. But the kidneys respond by excreting more bicarbonate to compensate, which can leave your baseline bicarbonate lower over time. Slow, relaxed breathing patterns help maintain normal CO2 levels, which in turn supports normal bicarbonate retention by the kidneys.
This isn’t a primary treatment for low bicarbonate, but it’s worth knowing that chronically fast or shallow breathing can work against you. Practices that emphasize slow diaphragmatic breathing may support the overall acid-base balance your body is trying to maintain.
Risks of Raising Bicarbonate Too High
Pushing bicarbonate above the normal range creates its own problems. Metabolic alkalosis, defined as too much bicarbonate in the blood, causes symptoms that can range from mild (lightheadedness, nausea, tingling in the fingers and around the mouth) to severe (confusion progressing to coma, heart rhythm disturbances, and dangerous drops in potassium). Low potassium is especially concerning because it can trigger cardiac arrhythmias independently.
The people most at risk for overcorrection are those who supplement aggressively without monitoring, those who combine multiple alkalinizing agents, and those with kidney impairment that prevents the body from excreting excess bicarbonate normally. If you have a known bicarbonate deficit, periodic blood work to check your levels and electrolytes is the safest way to ensure you’re correcting without overshooting.