Figure 3. Coffee and Diabetes Risk. Individuals who cut down their coffee consumption by 1 cup a day had a 17% higher risk of developing diabetes. Meanwhile, individuals who increased their coffee consumption by at least 1 cup had an 11% lower risk of developing diabetes. This data was obtained from 48,464 women in the Nurses' Health Study and 27,759 men in the HPFS study. Researchers used self-reported data over approximately 20 years.
Several studies have shown that coffee can decrease the risk of diabetes.
In one of the largest studies of its kind, researchers followed thousands of patients to see whether there was a connection between coffee and diabetes on the population level.
They found that individuals who began drinking more coffee per day had an 11% lower risk of diabetes.
Meanwhile, cutting down on your coffee consumption by around 1 cup per day correlated with a 17% higher risk of diabetes.
Researchers followed 7006 individuals in the National Health and Nutrition Examination Survey to see whether drinking coffee and drinking tea regularly had any effect on diabetes risk.
A second study found that this effect may be strongest in those who are already losing weight. Coffee drinkers who were already losing weight had a 65% lower risk of diabetes. Weight loss in general reduces your risk of diabetes. Drinking coffee appears to help.
Caffeine has been shown to be most healthy for your body and mind. There are certain negative effects that have come up in studies, however they are mostly specific to individuals with certain conditions such as anxiety and migraine headaches.
A small double-blind controlled trial, one of the best types of clinical studies, looked at how healthy individuals respond to caffeine intake. Participants were given capsules containing either a placebo (sugar pill), 100mg of caffeine, 200mg of caffeine, or 400mg of caffeine. Their metabolic rates were then measured by collecting their blood and their breath.
This data shows a strong correlation between coffee intake and diabetes. But, is there a plausible biological reason behind this?
One key reason behind this may be the effect of coffee on weight loss. One of the best prevention and treatment for diabetes happens to be weight loss.
Type 2 Diabetes is a disease driven by weight gain. Eating and drinking lots of calories can cause overwhelm your body's ability to deal with glucose. This causes glucose to build up in your blood, which is a condition that we call diabetes.
Based on the data showing that coffee helps burn calories, may help with weight loss, and that coffee reduces the risk of diabetes, it’s likely that coffee is beneficial for diabetes.
So far, the data shows evidence on the population level and the physiological level.
However, this research still has unanswered questions. As with any such research, it is possible that we are seeing a correlation rather than a causal relationship. For example, coffee drinkers may be inherently healthier people with or without any effects from coffee.
Of note, this study only looked at correlations, which do not imply causation. While causal relationships are correlated, correlated events are not necessarily causal. One common example is the link between churches and crime. The number of churches in a square mile is significantly correlated with crime. However, this is not evidence that churches cause crime. Rather, it reflects that fact areas with many churches have a higher populations.