The world's most commonly used psychostimulant is caffeine. For many of us that first cup of coffee helps us to get up in the morning. For some it becomes a ritual of sourcing the very best coffee beans roasted to perfection. For others, grabbing a coffee on the way to work, to meetings or for a break is just part and parcel of everyday life
The question is, apart from keeping our brain alert; does caffeine have any other benefit to our brains?
The research suggests yes it does and findings from a recent study suggest it could even be protective against the development of Alzheimer's disease.
When teaching brain fitness classes, one of the key lifestyle areas I discuss is nutrition and how adhering closely to the Mediterranean diet is best for helping to preserve memory and other cognitive skills. This diet includes leafy green vegetables, lean protein especially fresh fish, fruit, whole-grains, seeds and nuts and relatively little dairy. The extras to also add in include turmeric, green tea, dark chocolate, red wine and... coffee.
What's the evidence?
The research as part of an Alzheimer's research study was conducted in Florida and examined two groups of 124 people aged 65 and older. The participants all underwent cognitive evaluation at the start of the study along with blood levels for plasma caffeine and 11 different biomarker cytokines. The study continued with the participants being monitored cognitively over a 2-4 year period. Each participant was placed into one of five groups:
- Initial normal cognition and remained normal
- Initial normal cognition and then developed MCI*
- Initially had MCI and remained so
- Initially had MCI and converted to dementia
- Initially had dementia and remained so
(*MCI is mild cognitive impairment where a person has significant memory problems but has not declined to the level where a diagnosis of dementia has been made.)
The plasma caffeine levels checked at the first visit were found to be significantly lower in those categorised as having initial MCI compared to those with normal cognition. There was also a difference between those with dementia compared to those who did not, but this difference was not statistically significant.
In those who converted from MCI to dementia over the course of the study they were found to have initial plasma caffeine levels 51% below the levels of those who had MCI and who maintained so.
In both cohorts, having a baseline level of plasma caffeine greater than 1200ng/ml if you already had MCI, was associated with a 100% chance of avoiding progressing to dementia during the 2-4 year follow up.
So how much coffee drinking will produce the 1200ng/ml level?
This will depend on the strength of the coffee, but an average of 3-5 cups a day will provide 500mgs of caffeine.
Previous animal studies showed that drinking 100-200mgs of caffeine a day did not produce this dementia saving effect.
However it is of course important to realise that drinking coffee alone is not the holy grail of dementia prevention. There are a number of different environmental and genetic factors at play. Caffeine consumption is another factor to consider along with: being physically active, managing other risk factors such as blood pressure, cholesterol and diabetes and getting lots of antioxidants from fresh fruit and vegetables.
There are a number of people who are quite sensitive to caffeine who would not be able to tolerate this amount of coffee on a regular basis without running the risk of bouncing off the walls or experiencing unpleasant palpitations and jitteryness. If this is you, then obviously caffeine is not something you would choose in your arsenal of dementia protection. However for those who can tolerate greater quantities it could be a way to help maintain cognition.
Caffeine can be taken as an enjoyable way for us to obtain some valuable antioxidants and anti-inflammatory compounds.
It has also been shown to suppress certain brain enzymes involved in stimulating amyloid production and increasing certain plasma cytokines required to stimulate new synaptic connections and neurogenesis.
So there are certainly benefits to our brain function from drinking coffee.
This is an interesting study that highlights that many components of what we do, what we eat and drink; how we choose to live our lives contribute to our likelihood or not of developing dementia as we age.
But, this is only a single study on a relatively small population, so the findings while interesting require further follow up to determine how much protection coffee drinking really does afford and how this all fits in with everything else.
Meanwhile I shall continue to indulge in my enjoyment of a good cup of coffee in the mornings.
Chuanhai Cao, David A. Loewenstein, Xiaoyang Lin, Chi Zhang, Li Wang, Ranjan Duara, Yougui Wu, Alessandra Giannini, Ge Bai, Jianfeng Cai, Maria Greig, Elizabeth Schofield, Raj Ashok, Brent Small, Huntington Potter, Gary W. Arendash High Blood Caffeine Levels in MCI Linked to Lack of Progression to Dementia Journal Of Alzheimer's Disease. Volume 30, Number 3, June 2012 Pages 559-572