By Annie Hauser

People with diabetes have a higher risk of dementia. But could dementia actually be a type of diabetes?

Some researchers say yes. The disease that affects millions of Americans -- Alzheimer's -- is actually "type 3" diabetes, not a separate condition, some say.

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In clinical practice today, there are three types of diabetes: type 1, which has no known cause or cure and is typically diagnosed in childhood; type 2, called the "lifestyle" diabetes, though it is also caused by ethnicity and family history; and gestational, which strikes pregnant women and in 90 percent of cases goes away after women give birth.

But as food writer and health advocate Mark Bittman writes in a recent New York Times op-ed, the idea that Alzheimer's is actually just another form of diet-induced diabetes was introduced in 2005 by neuropathologist and professor at Brown Medical School, Suzanne de la Monte, MD, MPH. In her research, de la Monte demonstrated that levels of insulin and its receptors diminish significantly in the brain during early Alzheimer's -- and this trend continues as the disease progresses.

"And many of the unexplained features of Alzheimer's, such as cell death and tangles in the brain, appear to be linked to abnormalities in insulin signaling. This demonstrates that the disease is most likely a neuroendocrine disorder, or another type of diabetes," she wrote in a press release when the study was published in the Journal of Alzheimer's Disease.

The "why" makes sense once you know how insulin works. Insulin is how your body regulates blood sugar -- it prompts cells to pick up sugar from your blood and use that sugar as energy. When you eat a high-fat, high-sugar diet (as many Americans do), the cells are overwhelmed by all the sugar and stop reacting well to insulin. This is called insulin resistance, a condition that if left untreated, leads to type 2 diabetes.

All the sugar that's left in your blood stream by insulin resistance then wreaks havoc over the rest of your body, causing heart disease, nerve damage, eye damage, and more. When this damage reaches your brain cells, you lose memory function and become disoriented. Or in other words, some researchers say, you develop Alzheimer's.

Alzheimer's and diabetes rates are both on the rise. And as the population ages, Alzheimer's disease rates will "escalate rapidly in coming years," the Alzheimer's Association reports. It's believed that Alzheimer's is brought on by a combination of genetics, environmental, and lifestyle factors -- but the type 3 diabetes idea adds new credence to the suggestion that diet and exercise, more than any other factor, can prevent Alzheimer's.

The omega-3 fatty acids found in fish, walnuts, and flaxseed have been shown to decrease risk of cognitive decline, as have the antioxidants in fruits, vegetables, and tea -- foods that have all been shown to help prevent type 2 diabetes. The answer, healthy eating advocates like Bittman say, is adopting a "sane" diet full of plants, and low in saturated fat and sugar to head off cognitive decline, diabetes, and the host of negative side effects that come with.

Also on HuffPost:

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  • Daily Chores And Exercise

    A recent study in the <a href="http://www.neurology.org/content/early/2012/04/18/WNL.0b013e3182535f0e.extract" target="_hplink">journal <em>Neurology</em></a> showed that simple activities like <a href="http://www.huffingtonpost.com/2012/04/20/chores-alzheimers-exercise-_n_1440969.html" target="_hplink">cooking, cleaning and washing the dishes</a> -- as well as good, old-fashioned exercise -- is associated with a decreased Alzheimer's disease risk, even among people who are age 80 and older. <br> <br> Researchers found that the people who were the least active each day -- in the bottom 10th percentile in the study -- were two times more likely to go on to develop Alzheimer's disease, compared with people who were in the top 10th percentile for daily activity. <br> <br> The results were even more marked when evaluating the intensity of physical activity: Those who were in the bottom 10th percentile for physical activity intensity were three times more likely to develop Alzheimer's, compared with those in the top 10th percentile.

  • Speak Two Languages

    Being bilingual could strengthen your brainpower and protect against dementia, according to a recent study published in the <a href="http://www.cell.com/trends/cognitive-sciences/" target="_hplink">journal <em>Trends in Cognitive Sciences</em></a>. <br> <br> HuffPost Canada Living <a href="http://www.huffingtonpost.ca/2012/04/02/benefits-of-being-bilingual_n_1396671.html" target="_hplink">explains why</a>: <br> <br> <blockquote>The anticipation of having to speak one of two language at any given time forces the brain to run continually, and results in an experience that helps avoid a mental conflict between languages.</blockquote> <br> <br> "It is rather like a reserve tank in a car. When you run out of fuel, you can keep going for longer because there is a bit more in the safety tank," study researcher Dr. Ellen Bialystok <a href="http://www.guardian.co.uk/science/2011/feb/18/bilingual-alzheimers-brain-power-multitasking" target="_hplink">told <em>The Guardian</em></a>.

  • Consume Curcumin

    Research in flies suggests that the main compound in turmeric, called curcumin, could have powers against Alzheimer's. <br> <br> <em>The Telegraph</em> reported on a study in the journal <em>PLoS ONE</em>, which suggested that <a href="http://www.telegraph.co.uk/health/healthnews/9084973/Having-a-curry-could-help-ward-off-dementia.html" target="_hplink">curcumin may work</a> by reducing the amount of oligomers, which are the "precursor" forms of amyloid plaques in the brain. <br> <br> A previous study in the journal <em>Annals of Indian Academy of Neurology</em> discussed the possible <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2781139/" target="_hplink">effects of curcumin on Alzheimer's</a>. Researchers wrote: <br> <br> <blockquote>Due to various effects of curcumin, such as decreased Beta-amyloid plaques, delayed degradation of neurons, metal-chelation, anti-inflammatory, antioxidant and decreased microglia formation, the overall memory in patients with AD has improved.</blockquote>

  • Do Puzzles

    <a href="http://www.huffingtonpost.co.uk/2011/12/01/puzzles-and-exercise-help-beat-dementia-symptoms_n_1122502.html" target="_hplink">Doing some puzzles</a> and playing games every day could ward off mental decline, according to a recent study in the journal <em>BMC Medicine</em>. <br> <br> Researchers from the University of Erlangen conducted a study in dementia patients in nursing homes, and had the study participants do exercises like bowling and solving puzzles together, the Press Association reported. They also spent some time doing things like woodwork and gardening. <br> <br> The researchers found that all of these activities seemed to have the same effect on the study participants' <a href="http://www.huffingtonpost.co.uk/2011/12/01/puzzles-and-exercise-help-beat-dementia-symptoms_n_1122502.html" target="_hplink">brain functioning</a>, compared with the typical dementia medication, the Press Association reported. <br> <br> Another recent study in the journal <em>Archives of Neurology</em> showed that life-long reading and game-playing could <a href="http://www.medicinenet.com/script/main/art.asp?articlekey=153901" target="_hplink">decrease beta amyloid levels</a> in the brain, which are considered a "hallmark of the condition," MedicineNet reported. <br> <br> "Staying cognitively active over the lifetime may reduce the risk of Alzheimer's by preventing the accumulation of Alzheimer's-related pathology," study researcher Susan Landau, a research scientist at the Helen Wills Neuroscience Institute at the University of California, Berkeley, <a href="http://www.medicinenet.com/script/main/art.asp?articlekey=153901" target="_hplink">told MedicineNet</a>.

  • Walk!

    Elderly people who <a href="http://www.bbc.co.uk/news/health-11537068" target="_hplink">walk six to nine miles a week</a> could decrease their risk of dementia and brain functioning problems, BBC News reported. <br> <br> The 2009 study in <em>Neurology</em> included 299 people whose average age was 78. Researchers found that people who walked the most in the study -- six to nine miles a week -- had a halved risk of developing the brain problems as people who walked the least in the study, according to BBC News. <br> <br> Similarly, a 2007 study that also appeared in the journal <em>Neurology</em> showed that people age 65 and older who regularly exercise have a <a href="http://www.eurekalert.org/pub_releases/2007-12/aaon-wam121107.php" target="_hplink">decreased risk of vascular dementia</a>. That study included 749 people.

  • Eat Your Fish And Nuts

    Researchers from Columbia University Medical Center found that eating a <a href="http://www.huffingtonpost.com/2012/05/06/omega-3-fatty-acids-alzheimers-memory-brain_n_1475806.html" target="_hplink">diet high in omega-3 fatty acids</a> -- such as fish, nuts and chicken -- is linked with lower levels of of beta-amyloid protein, which is linked with Alzheimer's disease. <br> <br> The study, published in the journal Neurology, included 1,219 people age 65 and older who didn't have dementia. The researchers found that the higher their consumption of the omega-3 fatty acids, the lower the beta-amyloid in the blood.

  • Drink Green Tea

    That refreshing green brew could have powers against Alzheimer's disease, according to research from Newcastle University. <br> <br> WebMD reported that when <a href="http://www.webmd.com/alzheimers/news/20110106/green-tea-may-help-prevent-alzheimers-disease" target="_hplink">green tea is digested</a>, the released compounds have protective effects against Alzheimer's. <br> <br> "When green tea is digested by enzymes in the gut, the resulting chemicals are actually more effective against key triggers of Alzheimer's development than the undigested form of the tea," study researcher Ed Okello <a href="http://www.guardian.co.uk/society/2011/jan/06/green-tea-alzheimers-cancer" target="_hplink">told <em>The Guardian</em></a>.

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