"Brain shrinkage" sounds scary enough. Seriously, who wants a shrinking brain?

But in reality, all our brains shrink a little over the years -- and in most cases it's nothing to worry about.

Some brains, however, shrink faster than others -- and since this rapid loss of gray matter is often a warning sign of dementia and Alzheimer's disease, you want to limit your own shrinkage as much as possible.

And the best way to do that is with the vitamins you should be getting anyway.

I've told you how B vitamins can help slow the shrinkage linked to dementia and stop or even reverse cognitive decline. Now, blood tests on 104 seniors with an average age of 87 finds that those with the highest levels of vitamins B, C, D and E have the biggest brains.

Not coincidentally, seniors with high levels of these key nutrients also did the best on tests that measured certain cognitive functions -- specifically, the ability to think, plan and solve problems. They also did better on tests measuring visuospatial skills and global cognitive function.

In plain talk, that means these vitamins can help keep your brain sharp enough to chase dementia away.

Along with those nutrients, make sure you get your share of omega-3 fatty acids -- because the same study found that seniors with the highest levels of these essential fats had better cognitive function and less damage to the white matter of the brain.

And don't forget while omega-3s can protect the brain, there's another type of fat than can rot it from the inside: the dangerous trans fats used in so-called "healthy" products like margarine.

Seniors with the highest levels of those trans fats, which you'll find in everything from coffee creamers to snack cakes, had smaller brains and did poorly on cognitive tests.

Keep in mind that food makers are allowed to round "low" levels of trans fats down to zero -- so don't trust the ingredients panel. Any product that has partially hydrogenated vegetable oils will have trans fats -- so avoid them, even if it says "trans fat free" on the label.

It's not the first study to show that nutrients can slow or stop dementia. As I mentioned earlier, B vitamins have proven time and again to prevent shrinkage, reduce inflammation and boost brainpower.

And while a good diet will include most of the vitamins you need to keep your brain sharp the exception to the rule is those Bs. You'll need more of those than what you'll find in food, so be sure to add a quality B complex to your regimen today.