Sorry for the over the top headline, but the answer to the question appears to be yes…and please read this whole post, there is something really good at the end.
How Being Overweight Affects The Brain
Researchers at the University of Pittsburgh scanned the brains of 94 people over the age of 70. They were looking to see the differences in the brains of people who were of normal weight (BMI under 25), overweight (BMI 25-30), and obese (BMI over 30).
If you are 5 foot 10 and you weigh 220, you have a BMI of 31.6 and would be considered obese. If you are 5 foot 10 and weigh 180, your BMI is 25.8 and you would be considered overweight for purposes of the study. There are certain athletes with lot of muscle mass that make the BMI inaccurate, but for the rest of us it is a valid measurement.
If you are 5 foot 5 and weigh 155 pounds, you would be considered overweight. At 185, you would be considered obese.
Don’t let the fact that all participants were over 70 distract you; this shows the effects of being overweight over time.
The Scary Results
It turns out that Obese people have 8% less brain tissue than people of normal weight. Overweight people have 4% less brain tissue than people of normal weight.
According to Dr. Paul Thompson, a UCLA professor of neurology, “This represents ‘severe’ brain degeneration, that’s a big loss of tissue and it depletes your cognitive reserves, putting you at a much greater risk of Alzheimer’s and other diseases that attack the brain… But you can greatly reduce your risk for Alzheimer’s, if you can eat healthy and keep your weight under control.”
*Source: Raji CA, Ho AJ, Parikshak NN, Becker JT, Lopez OL, Kuller LH, Hua X, Leow AD, Toga AW, Thompson PM. Brain structure and obesity, Hum Brain Mapp 2009 Aug 6
Losing Weight is not Just About Looking Good
It is kind of sad that “looking good” is the number one motivation for losing weight, but if that does the trick, then great.
However, to me, this new research is way more important. There is nothing more important than having a brain that works. It affects everything in your life, especially the people around you.
There are also a plethora of studies showing that being overweight decreases short term memory, and for lack of better words – can make you stupider and lazier than you otherwise would be.
And in case you forgot, being overweight also increases your risk of heart disease, Type 2 diabetes, hypertension, and has been shown to inhibit sexual performance.
More Bad News
The parts of the brain that degenerated for overweight people are very important, it wasn’t brain mass that we can spare.
Here are the areas effected:
- Frontal and temporal lobes: Critical for planning and memory
- Anterior cingulate gyrus: Responsible for attention and executive functions
- Hippocampus: Important for long-term memory
- Basal ganglia: Essential for proper movement and coordination
Furthermore, the brains of overweight people looked 8 years older than those of people of normal weight, and the brains of obese people looked a whopping 16 years older!
It is All About Eating
I hope that this article has helped motivate you to get to a normal weight if you aren’t already there. I think you probably know that there is really only one thing you can do in order to get there, and that is to eat the right foods at the right portions.
Exercise can help, but recent research demonstrates that exercise plays a much smaller role than calorie consumption. In fact, it can hurt your weight loss efforts if you aren’t careful because people seem to overestimate how much more they can eat after exercising.
So when you do exercise, make sure to track the calories burned and do not eat any more “extra” than what you have used. I am not saying not to exercise – just don’t exaggerate the effects in your mind.
Do You Have the Willpower?
If you have the desire to get to a normal weight and for whatever reason just can’t seem to get yourself to eat right, then you are not alone. Only about 5% succeed in losing weight over the long term.
These habits are hard to break, and we just aren’t designed to “not eat” the food that is around us. In this case, abundance is a double edge sword!
Furthermore, willpower is kind of a myth. We consciously only have the ability to exhibit conscious self control in one area at a time. I have written about the cookie study before, but I think it is worth repeating (in a very short form).
Subjects were brought into a room and asked to solve some brain puzzles. Another group was brought into the same room and asked to solve the same brain puzzles, but in this case they had a plate of cookies in front of them – and were told that they could not eat them!
The group that had to “not eat the cookies” performed dramatically worse than the group without cookies.
*Source: RE Baumeister, E Bratslavsky, M Muraven, and DM Tice. “Ego Depletion: Is the Active Self a Limited Resource?” Journal of Personality and Social Psychology, vol. 74, 1998.
This means that when you are trying to avoid “bad” foods, it affects just about every other aspect of your day. So when a bit of stress hits, bye, bye diet.
So unless you have a stress free life, or amazing self control – changing your eating habits consciously is a tough road.
There is Hope
This is leading somewhere! If you can’t make the change consciously, then you have to make these changes unconsciously. A great strategy for nudging your unconscious mind in the right direction is to control your environment. Get rid of the bad foods in your house and workplace. Put reminders on the refrigerator, plan and prepare your meals ahead of time, etc… the more you can do with your environment to prime your unconscious mind the better.
And if this isn’t enough, try hypnosis. Hypnosis is the ONLY scientifically validated method for training your unconscious mind to eat right (and this is without using willpower – which just doesn’t work). Hypnosis works at a totally different level in the brain. It actually works at the level of self image.
A Tool You Can UseAfter reading this post, I thought you would be interested in being able to find your own BMI. Here is a great resource. Just type in your height and weight.
http://www.nhlbisupport.com/bmi/
Also, please comment on the research at the beginning of this article – I respond to all posts.


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