Could eating a diet rich in flavanols lead to fat burning?
Research team investigates the effects of flavan-3-ols on fat metabolism.
As of 2013, 28.6% of the US population was obese (1). Obesity is not isolated to America. By 2030 40% of the world is expected to be overweight, and 20% obese (1).
Unfortunately, this is affecting children too. The number of overweight and obese children is expected to increase by more than half by the year 2025 (2). This has led to a greater number of children with Type 2 diabetes (2).
Doctors and researchers have worked to understand the mechanisms behind how the body stores fat. Once thought to be just a storage of reserved energy, scientists are discovering that fat tissue is an active endocrine organ (2).
Fat tissue also comes in different types. White fat tissue is the energy storage location (3). However, there is also brown fat tissue, which burns energy to create heat (2, 3). Humans have both white and brown fat tissues, but research has shown that brown fat tissue contains a large number of mitochondria, which help the body to metabolize fat (3). Brown fat tissue is metabolized with the help of a mitochondrial uncoupling protein 1 (Ucp-1) (4).
Scientists determined that the body can convert white fat tissue to brown fat tissue. Exposure to cold temperatures, exercise, and calorie restriction cause white fat tissue to convert to brown (4). Further, it was determined that activation of the sympathetic nervous system (SNS) was the root cause of the white fat tissues “browning” (4).
Another potential avenue for white fat browning is through diet (4). Scientists from the Graduate School of Engineering and Science, Shibaura Institute of Technology, Japan recently conducted a study of the effect of dietary polyphenols on activating brown fat tissue. Their results were published in the journal, Nutrients.
Dietary polyphenols are well known because they have been shown to provide health benefits (5). Flavan-3-ols are a type of polyphenol that behaves as an antioxidant, which may help prevent cardiovascular disease and lower cholesterol (5). They are commonly found in foods such as cocoa, green tea, cranberries, grape-seed oil, apples, and blueberries (5). Some studies have even shown flavan-3-ols may have a protective effect against various cancers (5).
The Shibaura Institute research team used flavan-3-ols derived from cocoa in two sets of experiments. In the first, mice were fed a single dose of flavan-3-ols, and their urine was collected and tested (4). In the second group, the mice were fed flavan-3-ols repeatedly over a two week period. Their fat tissue was then examined to determine the amount of white and brown fat tissue (4).
In the single dose experiment, the researchers found molecules which suggest the sympathetic nervous system was activated by the single dose of flavan-3-ols (4). In the multi-dose experiment, the results showed that some white fat tissue was converted to brown fat tissue (4).
The research team would like to conduct further research into how the white fat cells are converted to brown fat cells after eating foods high in flavan-3-ols.
- Meldrum DR, Morris MA, Gambone JC. Obesity pandemic: causes, consequences, and solutions—but do we have the will? Fertility and Sterility. 2017;107(4):833-839. doi:10.1016/j.fertnstert.2017.02.104
- Cypess AM, Kahn CR. Brown fat as a therapy for obesity and diabetes. Current Opinion in Endocrinology, Diabetes and Obesity. 2010;17(2):143-149. doi:10.1097/med.0b013e328337a81f
- Lazar MA. DEVELOPMENTAL BIOLOGY: How Now, Brown Fat? Science. 2008;321(5892):1048-1049. doi:10.1126/science.1164094
- Ishii Y, Muta O, Teshima T, et al. Repeated Oral Administration of Flavan-3-ols Induces Browning in Mice Adipose Tissues through Sympathetic Nerve Activation. Nutrients. 2021;13(12):4214. doi:10.3390/nu13124214
- Aron PM, Kennedy JA. Flavan-3-ols: nature, occurrence and biological activity. Molecular nutrition & food research. 2008;52(1):79-104. doi:10.1002/mnfr.200700137
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