Exploring the Link: Does Drinking Milk Cause Lactic Acidosis?

October 17, 2025 •

4 min read

Lactic acidosis is a serious medical condition stemming from severe underlying health issues, not dietary intake. Despite the shared term 'lactic,' the short answer to the question, does drinking milk cause lactic acidosis?, is no for the vast majority of healthy individuals.

Quick Summary

Drinking milk does not cause lactic acidosis, a severe metabolic condition resulting from impaired oxygenation or underlying disease, not dietary intake. Confusion often arises from lactose intolerance, where bacterial fermentation produces harmless lactic acid, and from the lactic acid created during intense exercise. In healthy people, the body effectively manages and clears lactate.

Key Points

No Causal Link: Drinking milk does not cause lactic acidosis in healthy people; it is a serious medical condition caused by underlying diseases or impaired oxygen delivery.
Lactose vs. Lactic Acid: Lactose is milk sugar, while lactic acid is an organic compound the body produces from glucose, especially during exercise, and can also be produced by bacteria during fermentation.
Lactose Intolerance is Different: Lactose intolerance is a manageable digestive issue where the body lacks the lactase enzyme. It causes gut-related symptoms, not a systemic blood pH problem.
Body's Natural Buffering: The human body has robust systems to regulate blood pH, and the mildly acidic nature of milk has no significant impact on this balance.
Rare Exceptions: D-lactic acidosis is a rare and specific medical condition associated with short bowel syndrome, not typical milk consumption.

The Fundamental Difference Between Lactose and Lactic Acid

To understand why milk does not cause lactic acidosis, it's crucial to distinguish between lactose and lactic acid. Lactose is the natural sugar found in milk, also known as "milk sugar." It is a disaccharide, or a double sugar, that the body breaks down into simpler sugars (glucose and galactose) using the enzyme lactase.

Lactic acid, on the other hand, is a three-carbon organic compound. In the human body, it is a byproduct of anaerobic metabolism, the process cells use to create energy when oxygen levels are low, such as during intense exercise. A temporary and harmless buildup of lactic acid can occur in muscles during a tough workout. Lactic acid is also produced by bacteria during the fermentation of lactose, which is how products like yogurt and cheese are made.

What is Lactic Acidosis, Really?

Lactic acidosis is a severe medical condition involving a dangerous buildup of lactic acid in the bloodstream, leading to an acidic blood pH. It is not a dietary issue caused by drinking milk but a symptom of a significant, underlying health problem.

Causes of lactic acidosis are complex and primarily fall into two categories:

Type A Lactic Acidosis: Caused by poor tissue oxygenation (hypoxia) due to severe medical conditions, including:
- Sepsis or severe infection
- Shock (cardiogenic or hypovolemic)
- Respiratory failure
- Heart failure
Type B Lactic Acidosis: Occurs without significant tissue hypoxia and can be caused by:
- Liver disease or kidney failure, which impairs the body's ability to clear lactate
- Certain medications (e.g., metformin, certain HIV drugs)
- Toxins or poisons (e.g., alcohol, cyanide)
- Specific inborn errors of metabolism

Gut Bacteria and D-Lactic Acidosis

There is a very rare and distinct condition called D-lactic acidosis, which involves a buildup of the D-lactate form of lactic acid, produced by intestinal bacteria. This is not caused by normal milk consumption but typically occurs in individuals with short bowel syndrome or other conditions that lead to bacterial overgrowth in the colon. The excess D-lactate is absorbed into the bloodstream, but this is a specific medical pathology, not a common dairy concern.

Understanding Lactose Intolerance vs. Lactic Acidosis

Confusion often arises because the term "lactic" is present in both lactose intolerance and lactic acidosis. It is vital to understand they are entirely different issues. Lactose intolerance is a digestive issue, while lactic acidosis is a severe metabolic disorder.


Feature	Lactose Intolerance	Lactic Acidosis
Cause	Insufficient production of the enzyme lactase, preventing the proper digestion of milk sugar (lactose).	Underlying medical conditions leading to a dangerous buildup of lactate in the blood.
Symptoms	Gastrointestinal distress, including bloating, gas, stomach cramps, and diarrhea, after consuming dairy.	Severe systemic symptoms, such as rapid breathing, fatigue, jaundice, confusion, and abdominal pain.
Mechanism	Undigested lactose reaches the large intestine, where bacteria ferment it, producing gas and small amounts of lactic acid, causing discomfort.	Impaired oxygen delivery or metabolic dysfunction causes the body to produce or fail to clear lactate, overwhelming the bloodstream's buffering capacity.
Severity	A manageable digestive discomfort that is not life-threatening.	A serious, potentially fatal medical emergency that requires immediate medical intervention.
Solution	Managing dietary intake of lactose through avoidance, lactose-free products, or lactase enzyme supplements.	Treatment of the underlying medical condition, often in a hospital setting.

Milk's Minimal Impact on Blood pH

Another myth is that milk consumption significantly alters the body's acid-base balance. The human body has highly effective regulatory systems, primarily involving the lungs and kidneys, to maintain blood pH within a very narrow, healthy range. Fresh milk is only slightly acidic (with a pH between 6.5 and 6.7) and is not considered an acid-producing food in a way that would trigger systemic acidosis. The idea that dietary factors like milk consumption can drastically shift the body's pH is a misconception not supported by medical science.

Why Does the Confusion Exist?

Several factors contribute to the persistence of this myth:

Confusing Terminology: The similar-sounding terms “lactic acid” and “lactose” often cause confusion, leading to an incorrect mental link between milk and lactic acidosis.
Internet Misinformation: Misleading online content sometimes promotes false connections between common foods like milk and serious medical conditions, feeding into public health anxiety.
Lactose Intolerance Symptoms: The very real and uncomfortable gastrointestinal symptoms of lactose intolerance, including bacterial production of lactic acid in the gut, might be misinterpreted as a more severe, systemic acid problem.
Fitness Misconceptions: The well-known association between strenuous exercise and temporary muscle soreness, which was once falsely attributed to lactic acid buildup, may also contribute to the misconception that lactic acid from any source is harmful.

Conclusion: A Clear Distinction for Your Diet

For healthy individuals, drinking milk does not cause lactic acidosis. The medical condition is a severe complication of underlying systemic issues and has no relation to normal dairy consumption. The discomfort associated with lactose intolerance is a digestive issue, not a metabolic one. Milk is a nutrient-dense food that provides important vitamins and minerals for most people. For those with lactose intolerance, consuming dairy alternatives or fermented products like yogurt can help them enjoy the benefits without the discomfort. If you have concerns about unexplained symptoms like rapid breathing, severe fatigue, or confusion, consult a medical professional immediately, as these could be signs of a serious underlying condition.

For more detailed information on metabolic health and acidosis, you can consult authoritative medical resources like the Cleveland Clinic or MedlinePlus.

Frequently Asked Questions

No, your blood pH is tightly regulated by your body's respiratory and renal systems. The small amount of lactic acid produced by bacterial fermentation during lactose digestion or the mildly acidic nature of fresh milk does not significantly alter your blood's overall pH.

The 'lactic acid' in fermented milk products like yogurt is produced by bacteria breaking down lactose. The lactic acid produced in muscles during intense exercise is a byproduct of anaerobic metabolism within your body's own cells.

No, being lactose intolerant will not cause lactic acidosis. The discomfort from lactose intolerance is a digestive issue caused by bacterial fermentation in the colon, which is completely different and much less severe than the metabolic failure seen in lactic acidosis.

The real causes of lactic acidosis are serious medical conditions, including severe infections (sepsis), shock, heart failure, liver or kidney disease, or certain medications.

No, fermented dairy products contain lactic acid produced by beneficial bacteria, but this does not cause lactic acidosis. In fact, fermented products often have less lactose and are easier for some lactose-intolerant individuals to digest.

The myth likely stems from a confusion between the words 'lactic' and 'lactose,' and a misunderstanding of how the body regulates pH and processes lactate. Misinformation and the distinct, though mild, symptoms of lactose intolerance also play a role.

For a healthy person, dietary intake does not influence lactate levels in a way that causes concern. Your liver and kidneys efficiently manage and clear lactate produced by both diet and exercise. Elevated blood lactate is a sign of a serious medical condition, not a dietary concern.