"Grain Brain": How your food choices can impact your brain's destiny

For many Americans, eating healthier will be a top new year's resolution – and one expert says we should start by eliminating gluten and sugars. Dr. David Perlmutter claims eating foods high in carbohydrates causes brain inflammation and can trigger neurological disorders like anxiety, depression and ADHD.

"I think it's really important to understand that the choices we make today while we're younger are going to have an effect on the brain as we get older. And once that happens, there's actually very little we can do. So prevention is the mantra of the day," Perlmutter said Tuesday on "CBS This Morning."  

The neurologist revised and updated his best-selling 2013 book, "Grain Brain: The Surprising Truth About Wheat, Carbs and Sugar — Your Brain's Silent Killers." He said simple sugars are the biggest issue – "anything that's going to raise your blood sugar." 

"There's a perfect correlation between even subtle elevations of your blood sugar, well below the range of diabetes, and future risks of becoming an Alzheimer's patient," Perlmutter said, adding that Type 2 diabetes patients quadruple their risk for Alzheimer's.  

"The bottom line is we know Alzheimer's is to a great extent a preventable disease. And a disease for which we have no treatment. So my mission has been for decades to really get that information out to you and the rest of the world, that our lifestyle choices are fundamentally important in terms of determining your brain's destiny," he said.  

In a statement to CBS News, the Sugar Association said it "believes that sugar is best enjoyed in moderation, and decades of research support this fact."

Perlmutter suggested three steps you could take to start your preventative routine.

"Get the sugar out of your diet, increase your dietary fat. Who knew? Fat is your friend," Perlmutter said. "Eat things like olive oil, nuts and seeds. Fat was taken off the table as we know for the wrong reasons 30 years ago. Reality is your brain needs fat."

Lastly, don't forget aerobic exercise, he said.