Supercharge Your Brain On A Low Carb Diet

  • It is generally believed that our brains need sugar to operate at peak efficiency. 
  • This argument has been one of the strongest indictments of low carb diets such as the Atkins Diet.
  • It may also be totally false.

In fact, according to a study published in the FASEB Journal, your brain, just like your muscles, works harder when fueled by lactate instead of glucose.

The Study

v021 Supercharge Your Brain On A Low Carb DietIn this study, researchers subjected their volunteers to strenuous exercise while looking at the blood running to and from their brains.

Specifically, they were trying to see what happened to the large amounts of lactate that are produced in the body as a by-product of exercise. Analyzing the blood entering and exiting the brain, the researchers found that “the brain was not storing the lactate which had come from the muscles during exercise, but rather using it as fuel”.

  • In fact, the brain helped to clear lactate from the body, shifting the supply of glucose towards the hard working muscles.
  • In addition, the data also showed that brain activity increased significantly during the study.
  • The brain was thriving on the diet of lactate.

From an evolutionary perspective, this isn’t surprising. If our prehistoric ancestors had not been able to think and react while evading four legged predators, they might literally have lost their heads.

Being able to use lactate as “brain food” allowed our ancestors to survive and evolve.

 Supercharge Your Brain On A Low Carb Diet

Doug Robb is a personal trainer, a fitness blogger and author, a competitive athlete, a social media nerd and a student of nutrition and exercise science. Since 2008, Doug has brought his real-world experience online via his health & fitness blog, Health Habits.

11 Comments

  1. Andrea Watson

    April 30, 2010 at 9:14 pm

    Low Carb diet is really the best diet if you want to reduce weight and also to maintain a healthy body.`-“

  2. Heart and Style Woman

    October 24, 2008 at 3:04 pm

    DR,

    Thanks for stopping by and commenting on my Diet Wars article. I’ve browsed through your site and appreciate the well-written, evidence-based posts.

    This a really interesting study. Wondering how this translates to the average person? Are there dietary recommendations from the study to maximize performance during exercise?

  3. DR

    October 22, 2008 at 4:22 pm

    Bloggy,

    Keep coming with the questions.

    Yours is exactly the attitude that we need when it comes to public policy concerning our health in general and our obesity problem in particular.

    A good scientist is skeptical…they don’t try to back up their beliefs by ignoring research or massaging test results to support their hypotheses.

    I am sure there is a lot more to this research.

    It may very well turn out to be completely wrong.

    But, then again…

  4. monica

    October 22, 2008 at 6:16 am

    There may be some debate around the glucose/lactate brain fuel research, but one thing is for sure: that Fox Trot is right on. =)

  5. McBloggenstein

    October 21, 2008 at 11:13 pm

    I agree that the argument that low-carb is bad for the brain is not a great one.

    I did not mean to imply that the research for lactate is not good.

    I was really just asking (because I don’t know) is what levels lactate are at when we are not exercising?

    The reason I ask this is because if the levels are very low between times of anaerobic exercise, then the brains of people that never exercise would not be getting this fuel that seems to be better than glucose, and this finding would only benefit those that exercise regularly.

    Which, of course, is a good reason to exercise. That doesn’t mean it’s a good reason to eat low-carb with the purpose of “supercharging” one’s brain.

    This is what I meant by saying “perhaps there is more to it”.

  6. Brian

    October 21, 2008 at 7:27 pm

    Thanks DR. I was just hoping to get out of a trip to the library :).

  7. Mark Salinas

    October 21, 2008 at 4:08 pm

    A very interesting article. McBloggenstein makes a valid point and your response is right on!

  8. DR

    October 21, 2008 at 3:05 pm

    Brian,

    I don’t have online access, but I read (and copied) the article from the journal at the U of Toronto medical library.

  9. DR

    October 21, 2008 at 3:03 pm

    Bloggy,

    This study is not the definitive word on neurobiology.

    It is simply the first step towards refuting the commonly held belief that the brain can’t function without glucose.

    The current RDI for carbs is based on this belief that our brains need 130 gms of glucose per day to function properly.

    This study opens doors to entirely new areas of brain research related to understanding lactate’s specific neurological effects.

    Researchers are now looking at lactate as a treatment modality for various brain ailments.

    Never mind the fact that it challenges one of the strongest arguments that mainstream obesity researchers rely on to refute a low carb approach to weight loss.

    I hope that this study allows mainstream researchers to feel free to investigate all avenues of weight loss research and not feel pressured into following the company line – calories in v.s calories out.

    Obesity research has become very politicized over the 50-100 years. This is not how we get good science.

    Good scientists should never set out to prove their argument. They should begin with a hypothesis, test that hypothesis, report the findings and begin again.

    Research into low carb has been marginalized for years. As a result, funding is hard to come by, and when it does, the research is criticized politically, not scientifically.

    I am hoping that research such as this serves to level the playing field

  10. Brian

    October 21, 2008 at 1:36 pm

    Great finds…Foxtrot and the article. BTW, do you have full access?

    McBloggenstein:
    Perhaps there is more to it than this. But does there have to be? And does it matter how long lactate is the primary fuel? If lactate is being produced, the time to exhaustion is shorter. So whatever we get is a bonus, no? And no, we are not anaerobically exercising all the time, which is why the brain uses glucose and/or ketone bodies.

    There is some research which suggests the brain performs better on ketones than glucose. So maybe the point regarding title of the post is to think about what the research is saying rather than just dismissing it.

  11. McBloggenstein

    October 21, 2008 at 2:48 am

    Perhaps there is more to it than this?

    I would say you should be more specific in how long lactate remains the primary fuel for the brain after a person is through exercising. What I mean is, we are not anaerobically exercising all of the time.

    So our brain is not feasting on lactate 24/7. What about other times? If weight lifting raised our lactate levels for long after exercise time is over, I would point that out.

    Otherwise, I feel as though your title suggests that a low carb diet is good for the brain, although I know you are just saying that the brain has “alternative fuels”.