The Effects of Weight Loss on the Brain
It is becoming more and more clear that the brain plays a crucial regulatory role in determining glucose homeostasis, energy homeostasis, eating behaviour, weight control, and obesity. People who are overweight typically have elevated levels of brain activity in (sub)cortical neuronal networks related to homeostatic control and hedonic responses. We don't know if dietary changes can affect these functional changes at this time. The current study set out to answer the question, "Does prolonged fasting and/or weight loss affect neuronal brain activity in obese people?" amongst those who fall into the latter category.
The study found the following.
The BOLD signal in regions of the brain involved in salience, sensory motor control, and executive control was reduced after an 8-week weight loss intervention. The level of leptin and the number of extra pounds a person carried were related to the BOLD signal in these regions.
Reduced brain activity in regions responsible for eating and evaluating rewards has been linked to successful weight loss. These findings suggest that changes in neuronal activity associated with obesity are related to excess body weight and may be reversed following successful weight loss.
Though most of the attention from the health and fitness community is focused on the physical effects of being overweight, such as insulin resistance, cardiovascular effects, bone and joint health, cancer risk, metabolic syndrome, and more, it's important to remember that weight can also have an impact on the brain.
One study, for instance, suggests that the increased risk of cognitive difficulties in children is due in part to the links between obesity and diabetes, hypertension, depression, and inflammation, and that these difficulties may persist into adulthood.
Does this mean that those who successfully lose weight also improve their intelligence and concentration? Not possible, I'm afraid. Certain short-term changes in the brain that occur during weight loss will not feel good. Recognizing the significance of the brain-body connection is helpful, as is being aware of how weight loss may affect mental processing.
If you've recently noticed a weight loss, this could explain it:
1) Your brain enters a sabotage mode when you're trying to lose weight.
You've decided to use YogPathWellness as a tool for keeping track of the foods you eat in order to help you reach your fitness goals. However, your mind continually warns you to take it easy while walking down the bakery aisle. How common is that?
Certainly worthy of note, academics. One study found that people who lost 10% of their body weight had lower levels of leptin than those who hadn't lost weight. Fat cells secrete a hormone called leptin, which signals satiety and causes you to stop eating. When body fat percentage is lowered, or fat cells are reduced in size, the body responds by decreasing leptin release to signal energy deficiency to the brain. When leptin levels drop, the brain reacts by trying to increase calorie intake, leading to a craving for fatty, high-calorie foods.
Extra sleep may help when this occurs.
Dr. Darria Long Gillespie, clinical assistant professor of emergency medicine at the University of Tennessee, says, "Sleep deprivation throws your leptin out of whack, and it's not helpful for your other hormones either." Improved hormone health can be achieved through a combination of sleep, exercise, reduced sugar consumption, and stress management.
2) You could physically gain weight in the head
Mark Hamer, PhD, of Loughborough University in England, points out that having a higher body mass index is associated with a smaller brain volume, which may cause cognitive decline with age. Those with excessive body fat around their middles felt this effect the most.
Possible explanation: cytokines, which are produced by your belly fat, are small proteins involved in cell signalling that become inflammatory when there are too many of them. A smaller brain size is a possibility if this occurs, as it can have a deleterious effect on several classes of neurotransmitters, as noted by Hamer. He also says that more research is needed to determine the extent to which weight loss can increase volume, but that getting rid of excess fat can reduce inflammation, which in turn likely affects brain volume.
According to Matthew Capolongo, NASM performance enhancement specialist and coach at New York's Professional Athletic Performance Center, losing weight due to cardiovascular exercise can also increase brain volume. He mentions that there is evidence linking this type of exercise, particularly high-intensity activity, to increased brain volume.
He says that if you have more brain tissue, your hippocampus, which is responsible for memory and learning, will grow, and that this could improve your ability to perform complex tasks, problem solve, and process information.
3) Dropping a few pounds refreshes your brain.
Women who underwent bariatric surgery reported improved performance on tests of executive function compared to results obtained before the procedure. This indicates that they were superior in the areas of strategy, organisation, and planning.
Dr. Cintia Cercato of the University of Sao Paulo, a co-author on the study, hypothesises that the women's increased brain sugar metabolism may explain the findings. Brain metabolic rates reverted to a lower, more normal level once the patients had lost weight following surgery.
Dr. Cercato stresses that the women did not start out lacking executive function skills; rather, their brains had to work harder because of the extra weight they were carrying. Thus, they found that losing weight was analogous to giving their brains a "tune-up," allowing them to function better.
On a concluding note,
The brain-body connection is complex in many ways, but one thing is certain: losing weight has an effect on your ability to think, remember, and process information.
Memory, focus, and problem-solving abilities of people who underwent weight-loss surgery improved in as little as three months, according to several studies.
In addition, fMRI studies show that people who successfully lost weight and kept it off for 9 months have altered responses to visual cues of high-calorie foods.
Areas of the brain involved in self-control showed increased activity, while those involved in processing rewards, motivation, and taste showed reduced responses.
Therefore, it may be easier to manage cravings if they are fought off at an earlier stage. As it turns out, like any other skill, mastering the art of weight loss takes time and effort.