One of the most surprising things I learned in nursing school was that the human body and the way it works is not always logical. Sure, when you drill down deep enough, the sciences of biology and chemistry make the body more understandable, but science has continued to change it's understanding of our bodies and the world since we were all in high school.

Much of the old science and health information you were taught (and which, unfortunately, is still being taught in some places) is no longer considered true by those who are up-to-date with current nutritional research. This means that some of your so-called "healthy" habits might actually be hurting your brain.

Here are 3 persistent food myths that could be sabotaging your productivity:

1. Eating FAT is BAD for your health.

Your brain is 60% fat, so when you don't get enough dietary fat, you're actually denying your brain. Let's think back to when fat started getting it's bad rap--it was in the days when people believed in "better living through chemistry" and no one worried about trans fats, hydrogenated vegetables oils, and overly processed, "fake" foods.

Fats such as coconut oil and olive oil have been correlated with neuroprotective (i.e. brain-protecting) benefits and since it appears they can decrease the risk of Alzheimer's and dementia later in life, why not bring these healthy fats into your diet now? (It's easier to prevent than it is to cure.)

And for those of you worried about cardiovascular health and dietary fats, see what the New England Journal of Medicine reported about the benefits of a Mediterranean diet supplemented with additional fats. (Bottom line: they stopped the trial after 4.8 years, because the low-fat diet was clearly correlated with a higher incidence of heart attacks, strokes, or deaths from other cardiovascular disorders.)

2. Sugar is okay in moderation.

This one really depends on what you mean by moderation. One pastry each morning with your coffee is not moderation; one a month could be.

The problem is that sugar is an addictive substance that has an opiate-like effect on the brain. It has been shown to worsen mental health issues (including depression and anxiety), and decrease learning and memory.

David DiSalvo, a science writer whose articles have appeared in Forbes, Psychology Today, The Wall Street Journal and other publications concludes this about sugar:

"What these and other studies strongly suggest is that most of us are seriously damaging ourselves with processed foods high in added sugar, and the damage begins with our brains. Seen in this light, chronic added-sugar consumption is no less a problem than smoking or alcoholism."

And no, you can't replace your sugary soda with a diet one. Aspartame is neurotoxic, and has been shown to cause problems from "fuzzy thinking" to seizures since the 1980's.

3. That cup of coffee counts towards your recommended daily water intake.

Nope, sorry. Anything that dehydrates you (such as caffeine), can't count towards your daily water intake. In fact, if you're drinking caffeinated or dehydrating beverages (like alcohol), you need to drink more water than your recommended daily amount (one common formula is 1/2 of your body weight in ounces, so a 200-pound person would need 100 ounces of water daily), to make up for the dehydration.

According to Daniel Amen, MD, author, and well-known brain researcher, "anything that dehydrates you is bad for the brain, such as alcohol, caffeine, excess salt or not drinking enough fluids."

* * *

In business, your brain is one of your best resources. Just like we update our software and computer technology, it's critical to update our understanding of how our bodies function. Keep your brain running with today's best recommendations: get lots of sleep, eat more healthy fats, limit sugar/ sweeteners/ processed foods, and drink plenty of water!

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Published on: Dec 29, 2014
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