Sugar rush or sugar crash? A meta-analysis of carbohydrate effects on mood

NEUROSCIENCE & BIOBEHAVIORAL REVIEWS

I searched “carbs are the enemy” online and the first page of results attempt to explain why carbohydrates are not the enemy. One claim from Dr. John Berardi over at Percision Nutrition, noted that oversimplification is the enemy, which I think fits into all of nutrition science.

Most carb talk is directed toward weight gain/loss, but today we’re diving into the effects that carbs have on mood.

THE STUDY

31 RCT studies containing 1,259 participants investigated the effects of isolated carb ingestion and mood. They looked at mood changes 0-30 minutes after eating, then 31-60 minutes, and finally 61+ minutes post-meal.

Mood states included calmness, contentedness, anger, confusion, depression, fatigue, tension, vigor, and overall mood.

THE RESULTS

Put the chips away because the results revealed no positive effect of carbohydrates on any aspect of mood at any point following their consumption.

That said, eating a bunch of carbs was actually associated with slightly higher levels of fatigue and less alertness compared with placebo within an hour after eating. This was a small, and somewhat inconsistent finding, but nonetheless warns how snack selection impacts the way you feel.

TAKEAWAY
This study reminds us that a sugar-rush probably won’t improve your mood, but rather lead to a sugar-crash. To be clear, the findings were subtle and lean more towards “carbs don’t affect mood”. Luckily diet is an easy thing to self-experiment with, as we know food tends to affect everyone in different ways.