Key points
- Caffeine can increase ketone production, thereby helping people to achieve and stay in ketosis
- Caffeine can reduce insulin sensitivity and increase glucose but long-term studies show a net benefit of caffeine-containing drinks on diabetes incidence
- Caffeine can help to reduce migraine and headache pain but might possibly increase pain in some pain disorders
- Caffeine is a well-known cognitive enhancer that is also likely to have benefits to longer-term neural health
- [See out other coffee/caffeine articles for potential risks of caffeine]
Coffee and other caffeine-containing beverages are known to have a range of health benefits but the health and adverse effects result from a combination of chemicals within these plants and not just from caffeine.
Caffeine itself is mostly considered ‘ergogenic’ (performance-enhancing) but it may have some interesting health benefits aside from those in the beverages and foods in which it is found.
Caffeine and keto
Caffeine increases ketone production. Participants in a study evaluating the effect of caffeine on ketogenesis were given either 2.5 mg/kg or 5 mg/kg caffeine (approx. 1.5-4 cups of coffee depending on the participant body weight) or placebo and given a distinctly non-ketogenic diet of two pieces of toast with raspberry jam, a piece of cheese, applesauce and 100 ml of juice. Interestingly, even with this very non-keto meal, the caffeine groups achieved around 0.2 mmol/L BOHB compared to the control group who achieved only 0.1 mmol/L.1 Although this doesn’t mean caffeine will put you into ‘ketosis’ (NK) it does show that caffeine has a BIG effect on increasing ketone production, and so, has value for those trying to boost ketone levels.
Caffeine increases ketone production
Caffeine and diabetes
While 400-500 mg of caffeine has been demonstrated to increase blood glucose concentration (post-ingestion) by around 22% and insulin by around 33% (while also transiently reducing insulin sensitivity2),3 for a short time after consuming, it is unlikely to be a causative factor for diabetes as systematic reviews consistently show a correlation between coffee intake (containing caffeine) and a reduced risk of diabetes.4-7
Systematic reviews consistently show a correlation between coffee intake (containing caffeine) and a reduced risk of diabetes
Caffeine and pain
Caffeine is well known to be effective for helping to reduce migraine and headache pain but its effect on other pain disorders is unclear.8
Caffeine, brain health, and cognition
Caffeine is a well-known cognitive enhancer. Reviews of the evidence show that caffeine improves attention, vigilance, reaction times, and problem-solving (especially in sleep-deprived people).9, 10 Large scale reviews of the evidence show significant benefits from caffeine for positive mood and lower perceived fatigue. Doses of 12.5 mg up to 400-600 mg (<1 to 4-6 cups per day of coffee) provide a positive effect,10, 11 however, greater doses do not always provide greater benefits to cognition and mood, and typically, the first cup provides the majority of benefits.11 Interestingly, habitual users appear to experience greater cognitive or mood effects compared with low/non‐users.11 In addition to its acute effect on mood and cognition, caffeine-containing beverages may be protective against cognitive decline and dementia.12
Caffeine is a well-known cognitive enhancer
References
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