If the world seems crazier these days, it just may be.
Our brains are not impervious to 21st century revolutions in eating, environment and entertainment. In the case of the latter two, industrial pollution and synthetic chemicals in our midst (environment) as well as screens and comfy couches by which to passively observe (entertainment) have emerged as stark meddlers in our biology.
Food has changed drastically too.
One hundred years ago, most of mankind ate meat, fish, rice, potatoes, beans and vegetables from the garden. Honey was a special treat left for holidays.
Today, the menu of sweets is endless, with sugar infusing most processed foods, even things like pizza.
Sugar-stuffed pizza makes us rounder for sure but does it also make our brains fuzzier?
Earlier evidence from the scientific literature reveals:
- Diet can change the microbiota
- And microbiota can change brain and behavior
Putting it together, scientists then asked this question:
Can diet-induced changes in the gut microbes contribute to anxiety, memory or “cognitive flexibility”?
The study appears in Neuroscience in August 2015 as Relationships between diet-related changes in the gut microbiome and cognitive flexibility by K.R. Magnusson and colleagues.
- Mice were assigned to one of three groups: high-fat, high-sucrose or normal chow.
- An array of challenges was used: water maze, novel object and novel location testing were used to assess behavioral changes.
- High sugar group was impaired in both short and long-term memory compared to mice on normal chow.
- Both high-sugar and high-fat groups showed less cognitive flexibility by increasing focus on a former platform position.
- No differences were seen in step-down, exploration or novel recognitions.
A link was seen between microbes and cognitive flexibility: The authors conclude that “Higher percentages of Clostridiales and lower expression of Bacteroidales in high-energy diets were related to the poorer cognitive flexibility in the reversal trials.”
Takeaway? Munching on candy and washing it down with a venti frappe may not be the best way to study for exams. Sugar isn’t always so sweet.