The good and the bad
While the brain-protective promises of blueberry smoothies and omega-3-rich wild salmon may be seductive, the secret to staving off cognitive decline may be more fundamental and far less sexy. "I don't care how much you like blackberries," says Carol Greenwood, a professor at the University of Toronto and chair of an Institute of Aging committee at the Canadian Institutes of Health Research. "There is no nutritional 'magic bullet' for protecting brain function."
Instead, Greenwood focuses on risk factors that could lead to more than just lost keys. She points an incriminating finger at a culprit known more for hardening arteries and weakening hearts: obesity. "If you are obese, chances are you'll experience more rapid cognitive decline as you age and will be at higher risk for dementia."
In 2005, Greenwood and her colleagues fattened rats with a rodent version of a high-calorie North American diet. When tested, the obese rats displayed impaired thinking and were left in the dust by their leaner, quick-thinking counterparts. More recently, research has shown that an obese midsection may saddle you with a threefold increased risk for dementia. "We're not talking about someone who becomes obese in their seventies as being at such risk," explains Greenwood. "It's individuals who are obese in midlife who are at the greatest risk."
Your brain: the good, the bad and the bizarre
The good- Semantic memory improves with age and life experience, which enhances your ability to accumulate world knowledge, retain or learn vocabulary, and say, "I told you so"
- You maintain emotional regulation. In other words, your freak-out factor doesn't go up and you may even develop a more positive outlook
- The brain remains adaptable and is capable of cherry-picking different networks to compensate for memory loss elsewhere
- If memory tests are administered to older adults during their peak time (morning) and ask individuals to remember things they're actually interested in (the contents of the international buffet on an Alaskan cruise package, for instance), the elders can score as well as the young 'uns
- Exercise may encourage the growth of new brain cells
The bad
- Working memory can decline (affecting your ability to remember the prices of all your favourite cereals at the supermarket, long enough to require you to crunch the numbers to find the best deal by weight, for example)
- Episodic memory may fade (affecting your ability to remember exactly what you did three birthdays ago, and how your partner got you new splash mats for your car and that the congealed filet came two hours late. Maybe some things are best forgotten)
- It becomes harder to maintain focus without distraction
