Many people with gut issues suffer from cogitative issues and body-wide symptoms, along with the gastrointestinal hell they’re going through. One of the reasons is often high levels of D-lactic acid.
A few definitions
- acidosis – an abnormal decrease in pH levels. If systemic this is usually only a tenth of a pH level, or so, high.
- lactic acid (lactate) – an organic compound formed from fermentation, as well as by humans during normal metabolism and exercise. There are two main types discussed here D-lactic acid and L-lactic acid (two mirror-image isomers), DL-lactic acid is a mixture of the two in equal amounts. See Wikipedia for more information on D&L chirality prefixes.
- L-lactic acid – the type produced in the human body and the primary type found in the human diet. This form is easy for the body and rarely accumulates at a rate higher than the bodies ability to remove it. Short term acidosis is possible from l-lactic acid with extended strenuous exercise, but is usually cleared within a few hours. Acidosis can also occur with organ failure and other illness.
- D-lactic acid – this type is mostly foreign to the body and difficult to remove. It can easily build up, when it does this is called lactic acidosis. This article will refer it to as d-lactic acidosis to distinguish
- Lactate – In this context – the conjugate base of lactic acid, the two terms are used interchangeably.
Lactic acid actually isn’t the real culprit that causes the fatigue, brain fog, etc. (see below for symptoms). When lactic acid is formed in the body (by us during exercise, or by bacteria) hydrogen ions are formed, hydrogen ions lower the pH (make it acidic), hydrogen is the true culprit. Excess hydrogen causes problems of its own, but the increased systemic acidity is what causes many of the symptoms. If you’ve had a SIBO breath test you already know that hydrogen is a product of bacterial fermentation as the test measures both hydrogen and methane.
Normally the body can clear L-lactic acid in real time, this is done by the liver, kidneys and through respiration (through the lungs). Only if someone is really sick (e.g. cirrhosis of live, lung disease) or they’re exercising so strenuously, over time, that the body just can’t keep up. Even after strenuous non-stop exercise l-lactic acid is cleared from the body in about 60 minutes. But the muscle pain and fatigue of exceeding the bodies ability to remove l-lactic acid can go on for days! This is due to the inflammation it brought on. If you want to know more about l-lactic acidosis talk to a long distance runner, they can probably talk your ear off about it.
Symptoms of l-lactic acidosis include: a burning feeling in your muscles (inflammation), cramps, nausea, weakness, and feeling exhausted.
The above summarizes “normal” L-lactic acidosis; so what is D-lactic acidosis? This is where certain bacteria (see the partial list below) produce D-lactic acid. The body has a very hard time expelling D-lactic acid, therefore it tends to build up in the body quickly, and can linger for days (and remember the runner above? Even after d-lactic acid is cleared, the pain and other symptoms can last for another week after d-lactic acid is cleared!) The favorite fermentable food of D-lactic acid bacteria is simple sugars (including glucose, lactose and fructose). Have you ever felt considerably worse after that big cheat (maybe during the holidays), did you feel bad for a week after? This may have been the affects of D-lactic acid.
Symptoms of D-lactic Acidosis
- lack of muscle coordination (ataxia)
- balance and gait issues
- slurred speech (dysarthria)
- personality changes (grouchy, distant, angry, cold, hostile, aggressive, agitated, rarely – even abusive )
- memory loss (and brain fog, spaciness)
- fatigue (chronic fatigue syndrome-like symptoms, tired, lack of energy)
- “air hunger” (shortness of breath for no apparent reason)
- gas, bloating, distension, GI symptoms (unclear if these may have another common cause (e.g. SIBO) or they’re actually caused by d-lactate)
- symptoms get much worse after eating sugar or carbohydrates
Our brain is very sensitive to D-lactic acidosis (encephalopathy); D-lactate passes freely into the cerebral fluid 1. Common medical tests for lactic acid blood levels test for l-lactate, d-lactate is usually overlooked. D-lactate can also interfere with the body’s ability to utilize L-lactate as a source of fuel; the brain is especially sensitive to this. Research shows that up to 3% of people may have high D-lactate levels, this rate would be much higher in people with SIBO, dysbiosis in the colon, or a carbohydrate malabsorption 2. It is also possible that many of the symptoms people blame on die-off (Herxheimer reaction) may actually be d-lactic acid producing strains starting to proliferate, filling the gap of what ever bacteria you just killed; especially if the symptoms last for more than a couple of days.
People at the most risk for D-lactate acidosis are those with Short Bowel Syndrome, have SIBO, or malabsorb any sugars or carbohydrates. The last one is very important as it often goes overlooked and often exists with SIBO and other gut issues. For example, someone can have lactose intolerance without diarrhea; the lactose passes through the small intestine unabsorbed by us (because we may lack the lactase enzyme to breakdown the lactose (milk sugar) down into a usable form). This lactose then passes into the colon where it feeds undesirable (d-lactate producing) bacteria. D-lactate is formed and is absorbed into the blood and systemic environment, where it causes slightly lower pH levels (more acidic) and inflammation. Gas is also formed by the bacteria and can become trapped at the beginning of the colon (especially hydrogen, methane and hydrogen sulfide). This gas causes bloating, distension, and pain. You can also feel crummy for a week or more.
Common Causes of high D-lactate levels
- bacteria is the primary generator of D-lactate in mammals
- short bowel syndrome – where part of the small intestine has been removed or short due to a birth defect
- diabetic ketoacidosis (ketosis from a low carb diet will not raise d-lactate levels)
- diabetic low insulin production
- propylene glycol ingestion (antifreeze)
- roux-en-y gastric bypass surgery
- kidney or liver impairment
- Thiamine (Vitamin B1) deficiency – this is pretty rare in developed countries
- antibiotic use – antibiotics will leave the gut susceptible to opportunistic strains, which often produce large amounts of D-lactate.
What You Can Do About It
- Get SIBO under control – See The Gut Health Protocol many SIBO bacteria strains produce a lot of d-lactic acid, 24 hours per day.
- Fix any dysbiosis in the colon buy eliminating bad bacteria and rebuilding the beneficial bacteria in the microbiome. Again, see The Gut Health Protocol
- Avoid probiotics that contain d-lactic acid producing bacteria (see strains below). This means avoiding yogurt as it will always contain at least two d-lactic acid producing strains. There are few probiotics that meet this criteria. When you consume natural foods, that are naturally fermented without starter cultures (such as homemade kefir), the lactic acid often exists in the “DL” form. This is far less of a problem.
- Carbohydrate restriction, especially sugars
- Adequate hydration (avoid Ringer’s Lactate) – you must be well hydrated to clear D-lactate.
- Mind your malabsorptions! In other words, if you even think you might malabsorb lactose, fructose, sugar alcohols, etc. you must avoid them. Taking enzymes to counteract these malabsorptions (such as lactase for lactose malabsorption) only help, they do not completely eliminate the problem.
- If you can talk your doctor in to it, get tested for “D-lactate”, there is both a urine and plasma test. Both tests have to be sent to the Mayo Clinic for processing. (CPT Code 83605, Urine LOINC=14046-7, Plasma=14045-9). The Genova Organix® Dysbiosis Profile also tests for D-Lactate (available through many NDs, Functional Medicine doctors, etc). Stool tests are actually more likely to detect D-lactate than blood and urine tests as stool is where the producing bacteria are located and not all D-lactate passes into the systemic environment (e.g. blood). Insurance generally doesn’t pay for a D-lactate stool test.
Common D-lactic acid Producing Bacteria
- Opportunistic: Enterococcus faecalis, Streptococcus sanguinis, E. coli, Klebsiella pneumoniae, Streptococcus bovis, Bacteroides fragilis, and Candida freundii
- Common supplements: Lactobacillus acidophilus (yes, found in yogurt!), Lactobacillus bulgaricus (also very common in yogurt), Lactobacillus lactis (found in buttermilk), Lactobacillus buchneri, Lactobacillus delbrueckii subsp. delbrueckii, Lactobacillus delbrueckii subsp. lactis, Lactobacillus delbrueckii subsp.
bulgaricus, Lactobacillus jensenii, Lactobacillus vitulinus
The above is a partial list.
D-lactate Free Probiotic Strains
- L. plantarum – it was once believe to be a d-lactic acid producer. But more recent research shows that it produces both l-lactic acid and D-lactic acid in a racemic mixture (this is when equal amounts of left- and right-handed enantiomers (D&L) basically cancel each other out, at least for this discussion).
- Lactobacillus rhamnosus
- Bifidobacterium longum
- Bifidobacterium longum
- Bacillus subtilis and other Bacillus strains
The above is a partial list.
D-lactic acid symptoms are quite common in people with gut issues. Given that opportunistic bacteria frequently are D-lactate producers there is a good chance that blood levels for D-lactate are at least slightly elevated in these people. Reducing the D-lactate load is very important for these people. Avoidance of probiotic supplements containing these strains is a very good first step; unfortunately this does require avoiding yogurt. Getting rid of the D-lactate strains of bacteria in the gut is the next, and hardest, step. Again, The Gut Health Protocol can help with this.
1 Karton M, Rettmer RL, Lipkin EW. Effect of parenteral
nutrition and enteral feeding on D-lactic acidosis in a
patient with short bowel. JPEN J Parenter Enteral Nutr.
2 Tu1813 Brain Fogginess, Gas, Bloating and Distension: A Link Between SIBO, Probiotics and Metabolic Acidosis – Gastroenterology 2014;146(5):S850-1