Albert Anker's 1891 painting "Still Life with Coffee, Bread and Potatoes" shows some of what may go into a positive diet for mental improvement: caffeine and wholesome foods. (Public Domain)
It seems caffeine may enhance memory and learning, but not if it is taken before the lesson is to be learned. Research from a few years ago says caffeine should be taken after that important business meeting, crucial college lecture or other knowledge-imparting event you need to recall.
Some studies show a benefit from caffeine on memory, some show none. Same with alcohol. But it seems scientists find with few exceptions that good diets promote healthy minds and bodies.
Researchers led by Daniel Borota from the Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland, published a study in 2014 in the journal Nature Neuroscience stated in their abstract, "We conclude that caffeine enhanced consolidation of long-term memories in humans."
It was a complicated study in which 160 healthy women age 18 to 30 performed what a blog on Scientific American's website calls "a series of learning tasks."
Scientific American summarizes how the study was conducted:
The subjects were handed cards with pictures of various random indoor and outdoor objects (for instance leaves, ducks and handbags) on them and asked to classify the objects as indoor or outdoor. Immediately after the task the volunteers were handed pills, either containing 200 mg of caffeine or placebo. Saliva samples to test for caffeine and its metabolites were collected after 1, 3 and 24 hours.
After 24 hours the researchers tested the participants' recollection of the past day's test. Along with the items in the test ('old') they were presented with new items ('foils') and similar looking items ('lures'), neither of which were part of the task. They were then asked to again classify the items as old, new and similar. There was a statistically significant percentage of volunteers in the caffeinated group that was more likely to mark the 'similar' items as 'similar' rather than 'old'. That is, caffeinated participants were clearly able to distinguish much better between the old and the other items, indicating that they were retaining the memory of the old items much better than the people in the placebo group.
The authors attempted to differentiate between memory retrieval and consolidation by doing another test. Participants were given caffeine one hour before a learning task on the second day. There were no statistical differences between the placebo and caffeine subjects between a 200 mg dose and the 300 mg dose. There was a finding that 200 mg helped memory more than 100, however, suggesting a minimum dose is needed. The author said this warrants more study.
The Harvard Medical School blog had a 2015 posting citing some research that said diet and alcohol and caffeine may play a role in memory. That blog states:
If a study published in this month's Journal of Nutrition is any indication, the caffeine in coffee might offer not just a momentary mental boost but also longer-term effects on thinking skills. Having an alcoholic drink a day might also benefit our mental performance, but the line between just right and too much is uncertain. An even better strategy for maintaining memory and thinking skills with age may be to eat a healthy diet.
In the study, researchers from the National Institute on Aging compared scores on various tests of thinking skills and memory with caffeine, alcohol, and nutrient intake in 727 men and women taking part in the Baltimore Longitudinal Study of Aging. Over all, participants who ranked high on the healthy diet scale did better on 10 tests of memory than those with lower diet scores. The same held true for those who took in more caffeine. The effects for moderate alcohol drinking were mixed.
But if you are older and were hoping you might retain your memory better with a daily dose of caffeine, it does not appear to help, according to one study.
"The Journal of Nutrition study isn't the last word on the subject of caffeine and memory," Harvard Health writes. "It showed that people, particularly those who were ages 70 and over, who took in more caffeine scored better on tests of mental function, but not on memory tests or other measures of mental ability."
Harvard writes that the brain gets a "quick wakeup call after chugging a mug of coffee." The author says caffeine is believed to trick the brain because it is a stimulant in itself and because it blocks adenosine receptors, which normally prevent the brain from releasing more stimulating chemicals. When adenosine is blocked, the brain exciters are produced in greater numbers, giving a burst of energy and perhaps improving cognition.
It's important to note what Harvard says about these studies: "Some previous studies have shown improved long-term memory performance and thinking ability in regular caffeine consumers; others haven't shown any connection."
Benefits from drinking alcohol came only when men had no more than two drinks per day and women one drink per day. More than that and people suffer brain damage and short-term memory loss. One or two drinks a day improved working memory and attention.
It makes sense that this study found a good diet improved mental performance. Harvard wrote:
People who ate foods with plenty of healthful nutrients had better attention and memory than participant with poorer diets. A healthy diet was also linked to good thinking skills in women and participants under age 70. In particular, foods that are part of the Mediterranean diet, fruits, vegetables, nuts, fish, olive oil, and whole grains, show promise for preserving memory and preventing Alzheimer's and other forms of dementia. This study is just one of many linking healthy eating habits with maintaining memory and thinking skills into old age. Continuing a healthy diet, or switching to one, makes sense on many levels. It probably is good for your brain, and it's definitely good for your heart, bones, muscles, and overall health.In terms of memory loss or enhancement, caffeine, diet and drinking, it seems like age-old common sense is a good guide: a lot of good things, but all in moderation.
Is there a big difference between synthetic and natural caffeine? Which gives a stronger jolt? Does it even matter?
Natural caffeine in coffee, tea, and chocolate is much less common than the synthetic caffeine found in so many other products.
Caffeine is found in plant species such as the more popular ones like Coffea arabica and Coffea robusta, as well as tea leaves, kola nuts, cacao beans, Yerba mate and guarana berries.
Not only does naturally-occurring caffeine from said plants keep your cognitive functions at their peak, but it also contains antioxidants that help you fight illnesses like cancer and Alzheimer’s.