How Low-Carb Diets Can Affect the Brain
The Effects of Carbohydrate Restriction on Memory and Learning
Dec 28, 2008
Following a low-carb diet has been shown to have many benefits such as weight loss, reduced cholesterol levels, and lowered blood pressure. However, according to the Institute of Medicine, the brain needs at least 130 grams of carbohydrates per day in order to function properly. Most low-carb diets require fewer than 130 grams of carbohydrates daily, especially during an "induction phase" when it is common for dieters to only consume 20 grams of carbs. Although until recently there has been little research regarding the effects of a low-carb diet on brain functioning, the latest research finds that eating a diet low in carbohydrates does have a negative impact on brain functioning.
Why the Brain Needs Carbohydrates
While the brain's primary source of fuel is glucose, the brain cannot store it. So once carbs are broken down into glucose by the body, the glucose is then carried to the brain by the bloodstream where it is used immediately as energy by nerve cells. The brain uses glucose to perform many functions including thinking, short-term and long-term memory, and communication with other parts of the body. It stands to reason that when carbohydrates in the diet are restricted, the glucose that's available for the brain to use as energy is reduced.
New Research on Low-Carb Diets
The results of a new study to be published in the February 2009 issue of Appetite conducted by researchers from the psychology department of Tufts University show those who follow a low-carb diet perform worse on memory-based tasks and have a slower reaction time than those following a calorie-restricted diet. The findings of the study also show that once carbs are reintroduced into the diet of participants following a low-carb diet, cognitive functioning returns to normal, pre-study levels.
While the study was only conducted over a three-week period of time in total, results suggest that after only one week of severe carbohydrate restriction, a diet low in carbohydrates has a negative impact on brain functions such as memory and learning. More research is needed to determine whether this effect on brain functioning continues as a low-carb diet is continued or whether cognitive functioning returns to normal once the body adjusts to being on a new diet.
For further reading on the health risks of low-carb diets, see: Disadvantages of a Low-Carb Diet. To learn more about the types of carbs to include in a healthy diet, see: Good Carbs vs. Bad Carbs.
 |
