Thursday, September 15, 2011

Harvard's Brain Trust

The folks at Harvard are thinking about energy, and specifically, your energy.  But they don't see to understand where it comes from or how to optimize it.
http://view.mail.health.harvard.edu/?j=fe6116777167007c7111&m=febb15747d630d7a&ls=fde81d737062077c7d12757c&l=fe57157677630c7b7217&s=fe28167076600174771278&jb=ffcf14&ju=fe321771706c067c741173&r=0

Their thought process: 
The tried-and-true advice for healthful eating also applies to keeping your energy level high: eat a balanced diet that includes a variety of unrefined carbohydrates, proteins, and fats, with an emphasis on vegetables, whole grains, and healthy oils. Taking a daily multivitamin will ensure that you get the vitamins and minerals you need, but taking extra amounts of individual nutrients won’t give you more energy. In addition, eating certain types of foods in particular amounts can help prevent fatigue.

They are inexplicably uninformed about the glycemic properties of "whole grains":
Because different kinds of foods are converted to energy at different rates, some — such as candy and other simple sugars — can give you a quick lift, while others — such as whole grains and healthy unsaturated fats — supply the reserves you’ll need to draw on throughout the day. But limit the refined sugar and white starches to only occasional treats. While you may get a quick boost, that feeling fades quickly and can leave you depleted and craving more sweets.

Here's a useful bit of opinion by which one can prevent blood sugar crashes (but where tested, it has not proved helpful for weight loss).  Interestingly, though, it implies your body is unable to regulate blood sugars unless it is fed more or less continuously (perhaps because they eat all those whole grains?):
Where energy is the issue, it’s better to eat small meals and snacks every few hours than three large meals a day. This approach can reduce your perception of fatigue because your brain, which has very few energy reserves of its own, needs a steady supply of nutrients. Some people begin feeling sluggish after just a few hours without food. But it doesn’t take much to feed your brain. A piece of fruit or a few nuts is adequate.

Harvard is right on the money as regards drinking water.  They also state the obvious, which is you won't get an "energy boost" from drinking sugary drinks, or eating most "power bar" style energy bars, unless you have first put yourself into reactive hypoglycemia.  And that brings me to the most important point.

You can have all the energy you need, all day, without eating food all the time, and without having to feel dependent on food to avoid those nasty blood sugar crashes.

How?  Train your body to run on fat, of which you have enough stored already to last for weeks, perhaps more than a month, even if you are not carrying excess weight.

The best way to develop this metabolic flexibility is to restrict carbohydrate intake to less than 100g/day - and follow Mike Eades' advice about how to make the transition to a fat burning metabolism.

When you have the metabolic flexibility to run on fat, the body naturally runs most of you on fat, and saves the glucose needed by the brain.  Or, if needed, it makes more glucose from protein.  And if that's not enough, it also makes "brain food" (ketones, a glucose substitute) when needed by liver action on fat.  These processes are all normal, and far healthier than the mess that results when you stuff yourself with sugar all day via the never ending small meals. 

The only way the "multi small meals" advice is useful is if you can't tolerate enough fat to support true low carb eating (aka, you lost your gall bladder or some other medical issue, and cannot substitute coconut oil, which most in this category can).  But if you have concluded that low fat is good, and "whole grains" are good, you probably will have to eat the "multi small meal" way, as these Harvard writers have apparently discovered.

No comments:

Post a Comment