There are many dietary supplement strategies that can be used to support and promote your weight loss efforts in the gym and while you're dieting. Some of these strategies are old, and some are more recent; but rarely can you find a dietary supplement ingredient that approaches the issue of weight loss from an entirely new angle. Consequently, it's been very interesting for me to research and write about blueberry leaf extract.

Glucose And Fat Storage
To understand the contribution that Blueberry leaf can make to weight loss, we must first discuss the role of glucose (blood sugar) in relation to weight gain. First of all, glucose is obtained from sugars and other carbohydrates in our diet. All carbohydrates (except for fiber) are generally converted into glucose in our livers.1 The glucose is then used as a fuel in energy metabolism to help power our bodies. But what happens if our energy needs are already met; what does our body do with the glucose? Basically, a healthy body has two choices: it can convert a limited amount of it into glycogen (muscle sugar), and it can convert unlimited amounts of it into body fat which can be stored for an extended period of time.2 As a matter of fact, a small protein in liver cells is largely dedicated to helping convert excess dietary carbohydrates into fat stores.3

So, besides the obvious avoidance of excessive carbohydrates and sugar-laden foods, what can be done to inhibit this process of converting carbs into fat? There are three strategies, which can be used:

  • Reduce glucose absorption from the diet,
  • Reduce glucose synthesis in the liver,
  • Accelerate glucose metabolism.

Ideally, the most effective strategy would be to achieve all three at the same time.

Chlorogenic and Hydroxycinnamic Acids
Recent research has identified two unique natural compounds that appear to do just that. The two compounds are: chlorogenic and hydroxycinnamic acids. New studies suggest that taken together these two unique compounds:

  • May help to reduce dietary glucose absorption in the intestines,
  • Help reduce glucose synthesis in the liver, and
  • Speed up the metabolism of glucose—simultaneously.

Here's how it works: The enzyme glucose-6-phosphatase (G6P) plays a major role in the formation of glucose in our body. Chlorogenic acid was recently discovered to specifically inhibit the activity of this key enzyme. Inhibition of G6P activity in the liver results in a reduction of liver glucose production—which in turn may help reduce high rates of glucose output by the liver.4,5

In fact, both chlorogenic acid and hydroxycinnamic acid (aka, caffeic acid) are involved in the glucose reduction in our body. Research of Dr. Welsch and his colleges at Rutgers University reveals that glucose absorption in the intestines was reduced to 80 percent in the presence of chlorogenic acid and 30–40 percent in the presence of caffeic acid. These results suggest that both chlorogenic and caffeic acids are involved in the regulation of glucose level including the unique ability to inhibit dietary glucose absorption in intestines.6 Other recent research also indicates that the presence of caffeic acid accelerated the metabolism of glucose, which can reduce the total glucose concentration in circulating blood.7 Results of other studies provide further evidence that caffeic acid is involved in the reduction of blood glucose in diabetic animals.8

Pharmaceutical companies also actively interested in this important area of research have already synthesized several synthetic analogs of chlorogenic acid. These compounds are potent inhibitors of the glucose-6- phosphatase activity in the human liver.9 Other evidence has also confirmed that chlorogenic acid derivatives reduce blood glucose in animals, which also confirms the blood glucose lowering properties of chlorogenic acid.10,11

Therefore, it is strongly suggested from all the above that the effectiveness of chlorogenic and caffeic in glucose reduction will depend on whether these compounds are taken simultaneously and in sufficient amounts.

Blueberry Leaves

So, what does all this have to do with Blueberry leaves? Surprisingly enough, concentrations of chlorogenic and caffeic acids have recently been discovered in the Blueberry leaves (Vaccinium arctostaphylos L) found in the Caucasian Mountains of the northern region in the Republic of Georgia (in the previous Soviet Union). Interestingly, Caucasians have been using medicinal teas infused with leaves of the blueberry for the self-treatment of diabetes for literally centuries. In light of the previous information about chlorogenic and caffeic acids and their effect on blood glucose levels, this folk use of Blueberry leaves for diabetes makes sense.

Caucasian blueberry has a legendary reputation as aid to diabetics. Decoctions and infusions of the leaves are used in folk medicine as hypoglycemic agents and are usual major component of "anti-diabetes teas." Even more impressive, in Russia, a standardized blueberry leaf extract, known as "Diabetic Chai Cherniki" was effectively used for the treatment of diabetes, gastric colitis and high cholesterol, and has been repeatedly shown to contain pharmaceutically significant levels of both chlorogenic and caffeic acids.12

Now back to the concept of using Blueberry leaves extract as a strategy for weight loss. The logic is fairly simple: if you can reduce the amount of glucose that is absorbed, reduce the amount that is manufactured in the liver, and increase the rate at which glucose is metabolized, the result is that you'll likely be able to reduce the conversion of glucose into body fat. Of course, this does not mean that Blueberry leaves extract is a license to eat as much sugary and carbohydrate-rich foods as you'd like, but rather that if you're making an effort to eat a healthy, balanced diet, that Blueberry leaves extract can help prevent the carbohydrates that you are consuming into being converted to body fat. A good dose of blueberry extract is 200 mg.


  1. Whitney E, Cataldo C, Rolfes S. Understanding Normal and Clinical Nutrition, Fifth Edition (1998) West/Wadsworth, Belmont, California. pp. 114.
  2. Whitney E, Cataldo C, Rolfes S. Understanding Normal and Clinical Nutrition, Fifth Edition (1998) West/Wadsworth, Belmont, California. pp. 116–8.
  3. Yamashita H, et al. Proceedings of the National Academy of Sciences USA 2001;98:9116.
  4. Arion WJ, et al. Arch Biochem Biophys (1997) 15; 339(2):315–22.
  5. Hemmele H, et al. J Med Chem (1997) 17; 40(2):137–45.
  6. Welsch, et al. J Nutr (1989) 119(11):1698–704.
  7. Cheng JT, Liu IM. Naunyn Schmiedebergs Arch Pharmacol (2000) 362 (2):122–7.
  8. Hsu FL, Chen YC, Cheng JT. Planta Med (2000) 66(3): 228–30.
  9. Simon, et al. Arch Biochem Biophys (2000) 15; 373(2):410–28.
  10. Herling, et al. Eur J Pharmacol (1999) 386(1):75–82.
  11. Mshavanadze VV. Bulletin of the Georgian Academy of Science (1971a) 62:189–92.
  12. Mshavanadze VV. Bulletin of the Georgian Academy of Science (1971b) 62:446–7.

Gene Bruno, MS, MHS

Gene Bruno is the Dean of Academics and Professor of Dietary Supplement Science for Huntington College of Health Sciences (a nationally accredited distance learning college offering diplomas and degrees in nutrition and other health science related subjects. Gene has two undergraduate Diplomas in Nutrition, a Bachelor’s in Nutrition, a Master’s in Nutrition, a Graduate Diploma in Herbal Medicine, and a Master’s in Herbal Medicine. As a 32 year veteran of the Dietary Supplement industry, Gene has educated and trained natural product retailers and health care professionals, has researched and formulated natural products for dozens of dietary supplement companies, and has written articles on nutrition, herbal medicine, nutraceuticals and integrative health issues for trade, consumer magazines, and peer-reviewed publications. Gene's latest book, A Guide to Complimentary Treatments for Diabetes, is available on, and other fine retailers.