Outpatients of suspected metabolic syndrome with
normal liver enzymes, no excessive alcohol intake, negative for hepatitis B and
hepatitis C, no cirrhosis or chronic liver disease were subjected to liver
ultrasound to estimate the presence and degree of fatty liver disease. 25(OH) vitamin D levels were measured to
estimate any deficiency of vitamin D.
researchers found that patients with NAFLD had low levels of 25(OH) vitamin
D. They also found that the lower
25(OH) vitamin D levels, the worse is the degree of fatty liver disease
. This association was independent of other possible influencing
factors like age, sex, triglycerides, HDL and fasting blood glucose
Vitamin D suppresses fibroblast (cell from which
connective tissue develops) proliferation and collagen production, thus acting
as an immune-modulator. It also appears
to have a beneficial effect in patients with hepatitis C on treatment with
Vitamin D normally plays a role in the metabolism of
free fatty acids. Thus, the researchers suggest that in people with low vitamin D levels,
the excess free fatty acids flow in the blood stream. These deposit in the liver, resulting in NAFLD. Vitamin D's anti-inflammatory properties and
reduction in insulin resistance could also play an important role.
Further studies are warranted to evaluate whether
administration of vitamin D in patients with NAFLD could help to treat it, thus
firmly establishing the association between fatty liver disease and vitamin D.
Barchetta I et al Strong association between non alcoholic fatty liver
disease (NAFLD) and low 25(OH) vitamin D levels in an adult population with
normal serum liver enzymes; BMC Medicine 2011; 9:85.