For years, scientists have wondered about a possible link between Alzheimer's and Parkinson's disease, either in terms of genetics or environmental factors.


But a new study[1] shows that the two diseases do not appear to share a common genetic risk.


The study, by Dr. Valentina Moskvina of the Cardiff University School of Medicine [2] in Wales, examined genetic data from 3,177 patients with Alzheimer's and 7,277 control patients, as well as 5,333 patients with Parkinson's and 12,298 control patients. The gene-based analyses found no significant evidence supporting the presence of loci -- or the specific locations of genes -- that were associated with increased risk for both Alzheimer's and Parkinson's.


"Our findings therefore imply that loci that increase the risk of both Parkinson's and Alzheimer's are not widespread and that the pathological overlap could instead be 'downstream' of the primary susceptibility genes that increase the risk of each disease," the study authors concluded in a press release.


More than 5 million Americans are living with Alzheimer's disease, while Parkinson's affects 1 in every 500 people.

[3] [4]



Earlier on HuffPost50:




Loading Slideshow...



  • Make Your Meals A Rainbow


    That doesn't mean you should pour out a bag of Skittles at each meal. Try to eat foods of a variety of natural colors to gain antioxidants, said Dr. Amen.




  • Avoid These Fruits


    Just because something is a fruit, doesn't mean you should chow down on it, according to Dr. Daniel Amen, author of "Use Your Brain To Change Your Age." For brain health, Dr. Amen recommends food with a low glycemic index -- which measures how quickly food increases blood sugar -- and a lot of fiber, which benefits your intestinal tract. Certain fruit like pineapple and watermelon have high glycemic indexes and should be avoided, advises Dr. Amen. Instead, incorporate fruits like blueberries, apples, oranges, cherries, kiwi, strawberries and raspberries. When it comes to fiber, consider adding coconut to your diet. <em>Correction: In a previous version of this slide, "blood pressure" was incorrectly inserted where "blood sugar" is.</em>




  • You Need Fat


    Don't eliminate all of the fat in your diet. Instead, focus on incorporating good fats. In fact, if your cholesterol drops too low, you may be at greater risk for depression, according to Amen <a href="http://www.psychologytoday.com/blog/the-breakthrough-depression-solution/201106/low-cholesterol-and-its-psychological-effects" target="_hplink"> and several studies on low cholesterol</a>.

    So what exactly are "good fats"? Dr. Amen advises people to eat foods rich in omega-3s to promote brain health, including almonds, walnuts, brazil nuts, fish, lamb, avocados and green leafy vegetables.

    Another added benefit of eating good fats? "Your vitamins are actually absorbed better when you eat them with a little bit of fat," said Dr. Amen.




  • Choose Your Meat Wisely


    While you generally want to avoid bad fats, if you choose to eat steak, "you want to go with grass-fed, hormone-free, free-range meats" rather than grain-fed meats, said Dr. Amen. "When you feed the animals the high-glycemic foods, they actually produce less of the good fat and more of the bad fat. So they're not as good for you."

    In other words, what your food eats affects your health too, according to Dr. Amen.

    <em>Photo courtesy of <a href="http://www.flickr.com/photos/mdid/" target="_hplink">mdid</a></em>




  • Herbs And Spices Don't Just Add Flavor


    Next time you're whipping up some grub, turn to your spice rack for an extra brain boost. Spices and herbs may do more for your health than you realize. According to Dr. Amen, cinnamon balances blood sugar; garlic, oregano and rosemary increase blood flow to the brain; curry acts as an anti-inflammatory; and saffron can have anti-depressant effects.

    <em>Photo courtesy of <a href="http://www.flickr.com/photos/spence_sir/" target="_hplink">S. Diddy</a></em>




  • Pour Out That Juice


    Next time you're craving a cold glass of juice with your breakfast, think again. "Juice is sugar that is unwrapped from its fiber source, and whenever you unwrap sugar from its fiber source, it can turn toxic in your body," said Dr. Amen.

    <em>Photo courtesy of <a href="http://www.flickr.com/photos/mamchenkov/" target="_hplink">Leonid Mamchenkov</a></em>




  • What You Eat For Breakfast Matters


    You may be dreaming about that delicious breakfast muffin all night, but you should probably steer clear of the breakfast pastries. "There's way too much bad fat and sugar," said Dr. Amen. Instead, he recommends a protein-heavy breakfast like a few boiled eggs, nuts and an apple. While Dr. Amen suggests eating lean protein at each meal, he believes it is "especially important in the morning because it helps you focus," he said.

    <em>Photo courtesy of <a href="http://www.flickr.com/photos/15216811@N06/" target="_hplink">Nicola since 1972</a></em>




  • Find Supportive Friends


    The last thing you need when you're trying to eat healthy are friends who try to coerce you to be unhealthy. "You have to deal with the food pushers in your life because they'll steal your health," said Dr. Amen. "The health of the people you spend time with will often determine your longevity."

    Make sure your friends understand and support your decision to eat healthier, and try to find other people who who are on the same healthy path as you.




  • Related Video: Nutrition And Brain Health