Scientists at the University of Illinois at Urbana-Champaign fed rats a high-fat, high-sugar diet. They then gave some of the rodents caffeine extracted from tea and decaffeinated tea.


Caffeine: Study Results

The rats that consumed the caffeine extract gained 16% less weight and 22% less body fat compared to the control groups.

The weight reduction effects were similar among rats that consumed either synthetic, real  or decaffeinated caffeine.


Six groups of rats were fed a high-fat, high-sugar diet for 28 days. In addition, five of the groups were given one of the following:

  • synthetic caffeine,
  • tea containing this stimulant,
  • caffeine extracted from tea,
  • caffeine extracted from coffee,
  • decaffeinated tea.

The amounts were equivalent to that of humans drinking 4 cups of coffee per day.

After 28 days, there was a marked difference in lean body mass among the six groups of rats. The rats that had consumed caffeine from any source gained less body fat than the the control group.

There was a significant link between the storage of lipids in fat cells, the gain in body weight, and the increase in body fat.


Caffeine: How It Reduces Weight

Researchers also investigated the effects in cell cultures.

Fat cells from mice were exposed to all three types: synthetic, coffee extracted, and tea extracted.

Lipid buildup in fat cells decreased by 20–41%, across all groups.

It also reduced the ability of cells to produce long-chain fatty acids by 31 to 70 percent.


The imbalance between calorie intake and energy used by the body triggers storage of excessive triglycerides in fat tissues. The result is weight gain.

The World Health Organization (WHO) defines overweight and obesity as “excessive fat accumulation that may impair health.”


Why Obesity Is Dangerous

Obesity is a major health challenge worldwide. Once confined to higher-income nations, it is now also a growing health problem in middle- and low-income countries. At least 2.8 million deaths per year result from obesity and overweight.

Overweight and obesity are major risk factors for many chronic health conditions, including type 2 diabetes, fatty liver disease, and cardio-metabolic diseases.