In a study conducted at Duke-NUS Medical School, scientists found that B vitamins may treat non-alcoholic fatty liver disease in overweight and obese individuals. In particular, they discovered that vitamin B12 and folic acid might reverse the effects of non-alcoholic fatty liver disease.  

Nearly 25% of adults suffer from non-alcoholic fatty liver disease (NAFLD), the most common cause of liver disease in the United States. Meanwhile, almost 80% of obese individuals have NAFLD, which confirms the correlation between NAFLD and diabetes/obesity due to inflammation in the body. 

Non-Alcoholic Fatty Liver Disease 

Non-alcoholic fatty liver disease is a condition in which an individual has excess fat stored in the liver cells. As the name suggests, this type of fatty liver disease is not caused by excessive alcohol consumption but by excess weight. Non-alcoholic fatty liver disease is quickly becoming the most common form of liver disease. It coincides with other metabolic disorders such as obesity, insulin resistance, diabetes, hypertension, and cardiovascular disease.

Obesity contributes to NAFLD due to the inflammation caused by being overweight and excess insulin production in diabetic patients. Excess fat contributes to insulin resistance that forces the pancreas to produce more insulin to manage glucose levels, which is why diabetes is common in overweight individuals.

The increased insulin production causes excessive glycogen storage in the liver, ultimately increasing the presence of fat in the liver cells. Combined with the behavior of adipose tissue in overweight and obese individuals, where often the metabolism and rate of caloric burn have decreased due to fad dieting, the correlation between non-alcoholic fatty liver disease and obesity is significant.

If NALFD has not been discovered, monitored, and treated, it can lead to non-alcoholic steatohepatitis (NASH), an aggressive form of fatty liver disease. NASH is defined as inflammation in the liver and, if left untreated, could lead to an increased risk of liver cancer or liver failure.

Currently, there are no treatments for NASH, aside from a liver transplant, since scientists don't fully understand the mechanisms of this disease. 

B Vitamins

The B vitamins include: 

• B1 (thiamin)
• B2 (riboflavin)
• B3 (niacin)
• B5 (pantothenic acid)
• B6 (pyridoxine)
• B7 (biotin)
• B9 (folate [folic acid])
• B12 (cobalamin)

Vitamins B1, B2, B5, and B6, are critical for healthy skin, hair, muscles, nervous system, and brain function. These B vitamins are also essential in converting carbohydrates into energy.

Vitamin B9, otherwise known as folate or folic acid, is an essential nutrient in the production of DNA. B12 is one of the most common vitamin deficiencies after bariatric surgery. B12 is an essential nutrient for metabolic and nervous system health and helps break down fatty acids and amino acids to provide you with energy.

How B Vitamins May Treat Non-Alcoholic Fatty Liver Disease 

There are eight B vitamins, yet only three have been studied as a treatment option for non-alcoholic fatty liver disease—vitamins B3 (niacin), B9 (folate/folic acid), and B12 (cyanocobalamin).

Vitamin B3 plays an important role in lipid metabolization. In one study, it was found that B3 supplementation could result in decreased liver fibrosis. Conversely, another study found that B3 supplementation could lead to insulin resistance, exacerbating the effects of NAFLD. 

Despite the inconclusive results of B3 and its effects on NAFLD, vitamin B9 has shown positive results in treating this disease. A study on how B vitamins may treat non-alcoholic fatty liver disease found that low B9 (folic acid) levels could lead to an increased risk of NASH, while another study found that a folic acid deficiency was more significant in patients who had NAFLD. However, “it is not confirmed if this vitamin deficiency contributes to the incidence, exacerbation, and persistence of fatty liver disease.” Increasing folic acid levels has been shown to restore insulin resistance and hyperglycemia, which supports the statement that folic acid, a form of B vitamins, may treat non-alcoholic fatty liver disease. 

Finally, vitamin B12 influences DNA synthesis and repair often damaged in patients with NAFLD. The liver is the primary storage site of Vitamin B12, which suggests that elevated levels of B12 may help manage NAFLD. 

Ultimately, several studies have concluded that supplementing the diet with B vitamins may treat non-alcoholic fatty liver disease and end-stage liver disorders. Notably, vitamin B9 (folic acid) and vitamin B12 are found to slow the progression of NASH and reverse any liver inflammation. 

Dr. Brijesh Singh, a co-author of the Duke-NUS Medical School study, said, “Our findings are both exciting and important because they suggest that a relatively inexpensive therapy, vitamin B12 and folic acid, could be used to prevent and/or delay the progression of NASH.”