Rosemary May Boost Sugar Metabolism to Control Diabetes
Perhaps surprisingly, the woody perennial rosemary plant with blue flowers and a pleasant, pungent, pine fragrance, is a member of the mint family. Its Latin name, Rosmarinus officinalus, means “dew of the sea.” This is because it needs only the water carried by the sea breeze to survive. A firm favorite in the kitchen paired with garlic and lamb, an astringent tea made from the dried leaves also makes an excellent hair treatment, leaving it soft and shiny.
Rosemary – myths and legends
In Greek mythology, fronds of rosemary were draped about the goddess, Aphrodite, when she emerged from the foamy sea. According to a Christian legend, when the Holy Family fled to Egypt, a weary Virgin Mary spread her cloak over a white-bloomed rosemary bush to rest. The flowers turned from white to the same shade of blue as her cloak.
In ancient times, rosemary was believed to strengthen memory. For this reason, Greek scholars would wear the herb in their hair. In Australia and New Zealand, the association of rosemary with remembrance is observed every year on ANZAC day when, as the British wear poppies on Remembrance Day, Australians and New Zealanders wear a sprig of rosemary to commemorate their brothers and sisters who served and died in armed conflicts.
Rosemary and metabolism
Rosemary has long been under the microscope in animal studies as a potential player in helping to lower blood sugar levels and promote weight loss. Adding a simple extract of rosemary leaves to a high-fat diet fed to mice actually resulted in weight loss1
More recently, scientists in Maryland applied rosemary extract to the culture medium on Hep G2 cells, derived from a liver tumor in a 15 year-old Caucasian male2. This was an attempt to elucidate the biochemical mechanism by which the plant exercises its helpful effects on metabolism. Extract was infused at 2, 10 and 50 micrograms/millilitre and compared with a standard concentration of the diabetes drug, metformin. The rosemary extract increased glucose metabolism in the cells in a dose-dependent fashion, with the highest concentration being almost as effective as the metformin (21% versus 22%). The extract was shown to have several effects:
- Phosphorylation of AMP-activated protein kinase (AMPK) and its substrate, acetyl Coenzyme A carboxylate (ACC)
- Transcriptional regulation of several genes involved in glucose metabolism; namely, SIRT1, PPARγ coactivator 1a (PGC1α), ACC, low-density lipoprotein receptor (LDLR) and glucose-6-phosphatase.
This tedious list of genes was offered to introduce the interesting fact that the effect of rosemary on one of them, PGC1α, was reversed by a specific PPARγ antagonist.
What does this mean for you?
Let’s suppose you want to replicate the mouse experiments and use rosemary extract to counteract your high-fat diet. At 200 mg/kg, a 65 kg individual would need to use 13 grams of rosemary leaves every day for 50 days. Before embarking on this plan, make sure (a) you consult your doctor and (b) make room in your garden for several rosemary bushes.
Other ways of deriving the metabolic benefits of rosemary include slow cooking it in stews, soups and sauces, or popping a few sprigs into a bottle of vinegar and using it in salad dressings. A strong tea may be prepared using dried leaves and employing it as a hair rinse or even in a homemade shampoo. It is unclear how much would actually seep through the scalp to regulate your blood sugar, but you would have clean, shiny, sweet-smelling hair.
1 Harachi T, “Rosemary (Rosmarinus officinalis L.) leaf extract limits weight gain and liver steatosis in mice fed a high-fat diet.” Planta Medica. 2010.
2 Tu, Zheng, “Rosemary (Rosmarinus officinalis L.) Extract Regulates Glucose and Lipid Metabolism by Activating AMPK and PPAR Pathways in HepG2 Cells.”