Insulin resistance during pregnancy can lead to gestational diabetes, which affects about 5-10 per cent of pregnancies. According to the American Diabetes Association, about a third of women who suffered from gestational diabetes during pregnancy develop type-2 diabetes in the following years.
Blood levels of the vitamin-like substance L-carnitine are already significantly reduced by the 12th week of pregnancy, and are reduced further before birth.
According to findings published in the Journal for Obstetrics and Gynecology (Gynakologisch-geburtshilfliche Rundschau), daily supplements with two grams of L-Carnitine in the form of Lonza’s Carnipure tartrate during pregnancy may reduce levels of free fatty acids in the blood, high levels of which are thought to be the main cause of insulin resistance that increases the risk of developing gestational diabetes.
“Carnipure tartrate has clear benefits for pregnant women. It not only maintains normal L-carnitine levels but also decreases plasma free fatty acids, thus potentially decreasing the risk for developing insulin resistance,” said lead researcher Prof. Alfred Lohninger from the Medical University of Vienna.
L-carnitine occurs naturally in the human body and is essential for turning fat into energy. It is frequently used as a dietary supplement by physically active people to help with post-exercise recovery.
Lonza, which claims to be the world's largest manufacturer of L-Carnitine, has said that extensive scientific research shows the supplement promotes cardiovascular health and that other studies suggest the nutrient may be useful in weight management.
In terms of pregnancy, it has already been shown that levels of carnitine decrease during pregnancy, while the reason is unknown. A study published in the European Journal of Clinical Nutrition, suggested that this may be due to a decrease in the rate of carnitine biosynthesis, which may be due to an inadequate iron status in the women (Vol. 63, pp. 1098-1105).
Prof. Lohninger and his co-workers recruited 30 pregnant women in the 20th week of gestation and divided them into two groups: One groups received the L-carnitine supplements (2 grams per day) until week 38 of pregnancy, while the other group received a placebo. Twenty non-pregnant women also received placebo to act as an additional control group.
Results showed that pregnant women who received the L-carnitine supplements exhibited significant increases in the expression of carnitine acyltransferase enzymes, which play a role in the oxidation of fatty acids in the mitochondria – low expression of these enzymes are associated with increased levels of free fatty acids
Pregnant women in the placebo group however experienced increases in levels of free fatty acids.
“The present study showed that supplementation with 2 grams of L-carnitine per day resulted in a 5- to 10-fold increase in the relative mRNA levels of carnitine acyltransferases […], thus reaching values which were found in non-pregnant healthy adults,” wrote the researchers.
Source: Gynäkologisch-geburtshilfliche Rundschau (Journal for Obstetrics and Gynecology) Volume 49, Pages 230-235, doi:10.1159/000301075
“Relationship between Carnitine, Fatty Acids and Insulin Resistance”
Authors: A. Lohninger, U. Radler, S. Jinniate, S. Lohninger, H. Karlic, S. Lechner, D. Mascher, A. Tammaa, H. Salzer, H.