Type 2 diabetes mellitus (T2DM) is one of the leading causes of death in the world. The number of patients with this disease has dramatically increased, especially in developing countries. The International Diabetes Federation estimated that the diabetes population will reach 380 million globally by 2025.
Perhaps as a result of increased bad diet habits and physical inactivity, the prevalence of obesity as well as T2DM had increased in past decades.
The International Diabetes Federation proposed that the causes of increase in diabetes prevalence were because of population ageing, unhealthy diet, obesity and a sedentary lifestyle. Evidence also found that psychosocial stress, depression and environmental pollutants may affect the risk for T2DM.
A study conducted in China and several other studies have demonstrated the inverse association between coffee consumption and T2DM prevalence and fasting glucose levels. They have found that coffee consumption protects against T2DM in a dose response manner. Different mechanisms have been proposed to explain the association between coffee consumption and T2DM. Some of them are:
- Magnesium: a component of coffee and higher magnesium intake from food can improve insulin resistance, glycemic control and reduce the risk of T2DM. In the Chinese study they saw that serum magnesium levels increased with frequency of coffee intake and subjects without diabetes had greater serum magnesium levels than subjects with diabetes.
- Stimulation of thermogenesis and increased energy expenditure: this can result in weight reduction.
- Antioxidants: they promote insulin sensitivity, thus preventing or delaying the development of T2DM.
- Chlorogenic acid, quinic acid, trigonelline: these substances have been reported to improve glucose metabolism.
- Reduction of subclinical inflammation: which represents a potential link between coffee and diabetes risk.
How much coffee is considered protective?
- According to this study, coffee consumption of more than seven times per week is associated with a 63% lower risk for T2DM.
- Another study made in Singapore found that coffee intake of more than 4 cups per day reduced diabetes risk by 30%.
Source: Lin, W.-Y., Xaiver Pi-Sunyer, et al. Coffee consumption is inversely associated with type 2 diabetes in Chinese. European Journal of Clinical Investigation, 41(6), 659–666.