Penn State researcher Jack Vanden Heuvel has found that conjugated linoleic acid (CLA) given to mice successfully treats type 2 diabetes in a manner similar to that of antidiabetic drugs.
CLA is a fatty acid found in dairy products and meat, formed by the bacteria that exist within the cattle from which these products are derived. Earlier research involving CLA has shown that it helps prevent several cancers in mice, as well as reduces cholesterol and inflammation similar to the latest synthetic diabetes pharmaceuticals. "We wondered if CLA was using the same mechanism, in which case it could be used as an antidiabetes drug," Dr Vanden Heuvel stated.
Dr Vanden Heuvel, who is a professor of molecular toxicology at Penn State's College of Agricultural Sciences and codirector of Penn State's Center of Excellence in Nutrigenomics tested CLA on mice that develop adult onset diabetes, and observed an improvement in insulin action and a reduction in circulating glucose. He found that CLA turns on peroxisome proliferator activated receptors which interact with DNA. This results in a greater number of enzymes that process fatty acids, as well as an increase in insulin sensitivity--the same mechanism as that employed by diabetes medications.
"Antidiabetes drugs act the same way. They mimic the natural activators of the receptors by getting into the cell and interacting with the PPARs to regulate glucose and fat metabolism,” Dr Vanden Heuvel explained.
"And compared to the synthetic drugs used to treated this disease, CLA does not cause weight gain and may in fact decrease overall body fat," he added.
Doctor Vanden Heuvel cautioned that adopting a diet that is high in dairy and meat products to obtain CLA will also increase the intake of undesirable dietary fats. He suggests instead the use of dietary supplements containing CLA or products to which CLA has been added.
Related Health Concern: Obesity
Recent advances in dietary science have highlighted the crucial role of insulin in weight gain. Produced in the pancreas, insulin is a critical hormone for the control of blood sugar (glucose). Its job is to transport glucose into cells, where the glucose is burned as fuel. While this process is necessary for life, abnormalities in the insulin-glucose system caused by aging, lack of exercise and poor diet can cause major health problems. In aging, cells become more resistant to the effects of insulin. As cells become increasingly insulin resistant, the body compensates by increasing the number of insulin receptors on cells and secreting more insulin in an attempt to drive more blood sugar into muscle and liver cells (Fulop 2003).
Insulin resistance is a dangerous condition. Research suggests that adipose tissue (fat) is a source of pro-inflammatory chemicals that have a role in the development of insulin resistance (Sharma AM et al 2005). Insulin resistance is associated with obesity (in particular, abdominal obesity) (Greenfield JR et al. 2004).
This increase in insulin (called hyperinsulinemia) and decreased insulin sensitivity have a number of harmful effects, including contributing to diseases associated with being overweight (Zeman et al 2005; Garveyet al 1998)
Over time, high insulin and insulin resistance may lead to type 2 diabetes in susceptible individuals, a major risk factor for heart disease.
Many studies support the anticancer, antiobesity, antidiabetic, and antiatherogenic properties of CLA (Lee et al 1994; Park et al 1997, 1999; West et al 1998; Yamasaki et al 2003). Human clinical trials have shown reductions in body fat from CLA supplementation.
- Supplementation with 1.8 g daily of CLA for 12 weeks reduced body fat in healthy, exercising humans of normal body weight (Thom et al 2001).
- Men with abdominal obesity who consumed 4.2 g daily of CLA for 4 weeks decreased their abdominal diameter (Riserus et al 2001).
- Supplementation with 3.4 or 6.8 g of CLA daily for two weeks decreased body fat mass in overweight and obese people, and the trans-10, cis-12 CLA isomer inhibited the activities of the fat-storage enzyme lipoprotein lipase (Pariza et al 2001).
- The cis-9, trans-11 isomer, a specific isomer of CLA, increases metabolic rate and energy production (thermogenesis) (Ryder et al 2001; Brown et al 2003).