by Holly Lucille, ND, RN
In India, Alzheimer's disease is relatively uncommon. People over the age of 65 living in certain rural areas of India have a less than 1 percent (0.84%) chance of developing the disease. In the larger cities and rural areas of India, the risk is just 2.4 percent.(1,2)
Compare these findings to people over the age of 65 living in the United States. Again, depending on where we are living, our chances of developing Alzheimer's disease range from a little under 5 percent to an astonishing 17 percent.(3,4)
So what are people who are living in India doing that we aren't doing here in the US to account for these dramatic differences? The answer seems to be curry, that zesty spice and staple of Indian foods. Research has shown that a compound in curry not only prevents changes in the brain that lead to Alzheimer's disease, it actually reverses some of the damage already present.(5)
- How can curry prevent these changes in the brain? Isn't that a lot to expect from a spice?
Evidently, it's not too much to expect from this spice. Curry comes from the turmeric plant - Curcuma longa is the plant's official name. Curcumin, a plant compound in turmeric, is the source of curry's instantly recognizable bright yellow pigment. When it comes to the scientific research of Curcuma longa, the terms curcumin and turmeric are both used. Both refer to the same thing - turmeric extract.(6)
There have been more than 1300 studies on turmeric and its health benefits for humans. Research has shown turmeric is able to help the body get rid of cancer-causing toxins. Turmeric also blocks estrogen receptors and enzymes that promote cancer. And it's been found to stop the growth of new blood vessels in cancerous tumors - an important factor in keeping cancer from getting larger and spreading throughout the body.(7-9)
But one of turmeric's most exciting health benefits is its ability to reduce, prevent, and stop inflammation. While inflammation is a normal and needed response to injury or disease, chronic inflammation can cause damage to tissues. And researchers are now finding inflammation plays a huge role in Alzheimer's disease.
- I've always heard that Alzheimer's disease was caused by complex growths in the brain called plaques and tangles. How can simple inflammation cause such a devastating disease?
You are right. Plaques and tangles are indeed the hallmarks of Alzheimer's disease. But researchers looking at the brain damage caused by Alzheimer's have always noted the presence of inflammation wherever plaques and tangles form.(10) In the past, this inflammation was thought to be simply a consequence of Alzheimer's disease. Now scientists believe the inflammation itself starts a chain reaction ultimately contributing to the development of Alzheimer's disease.(11)
When cells in the brain are disrupted by inflammation, amyloid, a protein normally found in the brain, begins to act chaotically. This chaos results in the creation of beta-amyloid, a protein that is toxic to cells in the brain. Sticky deposits of beta-amyloid build up and collect around the cells, making dense clumps or plaques. Because the brain can't break the plaques down or get rid of them, they stay right where they are and slowly accumulate.(10,12,13)
Tangles result when long protein fibers that act like scaffolding for brain cells begin to twist and tangle. The cell is damaged and eventually dies. But the tangled proteins remain in the brain even after the dead neuron has been cleared away.(10,14) And inflammation might be the culprit causing the long protein fibers to start tangling.(15)
The consequence of these abnormalities of protein in the brain is more than the cell death they cause. They also act as roadblocks, interfering with electrochemcial messengers being shot from cell to cell. Therefore, the remaining healthy cells’ activity is diminished as well.
Research of identical twins has repeatedly shown that if one twin has Alzheimer's disease, the other has a 60% chance of developing the disease, too. Scientists from the Karolinska Institute in Stockholm, Sweden, looked at information from 20,000 twins collected in the 1960s and found 109 pairs of siblings where only one twin had been diagnosed with Alzheimer's. When the Swedish researchers analyzed data about the twins' health, they found the twin with Alzheimer's disease almost always had chronic gum disease. While bleeding gums are definitely not the cause of Alzheimer's disease, the inflammation that plays a large part of chronic gum disease may signal an inflammatory process stuck in overdrive.(16)
In fact, the inflammatory process might occur years before the onset of Alzheimer's, and be the result of any number of infections people can contract. That's why current research is searching for ways to protect brain cells from inflammation. And why some countries have low rates of Alzheimer's disease, like India.
- Why curry? Couldn't other lifestyle differences account for the low rates of Alzheimer's disease in India?
That's a good question. When researchers begin studying a disease, like Alzheimer's, they look for trends to help them determine how and why the disease occurs. For example, we all now know the connection between cigarette smoking and lung cancer. But, it wasn't until the 1930's that doctors noticed the trend for cigarette smokers to have more lung cancer than people who didn't smoke.(17)
So it has been with researchers studying Alzheimer's disease. They know Alzheimer's disease has an important connection to inflammation. They also know turmeric reduces inflammation. And when researchers noticed these trends - that people in India eat high amounts of curry from turmeric and have very little Alzheimer's disease - they began to theorize that turmeric might be able to prevent or even treat the illness. And the research they designed around these trends has unequivocally found turmeric to be one common denominator.(18-21)
- What have the turmeric studies shown so far?
Simply amazing findings are coming from curry research. Not only does turmeric slow down cancer growth, it's also been found to correct the cystic fibrosis defect in mice, help prevent the onset of alcoholic liver disease, and may slow down other serious brain diseases like multiple sclerosis.(22)
Researchers from the University of California Los Angeles (UCLA) studying turmeric have found it to be more effective than the drugs currently being investigated for Alzheimer's disease treatment and prevention. The researchers have discovered the actual structure and shape of turmeric allows it to penetrate the blood-brain barrier effectively and bind to beta amyloid.(23) Other research findings shows turmeric helps remove beta-amyloid that's already built up in the neurons.(24) Turmeric helps maintain healthy brain cellular metabolism, helps the cells repair themselves, and keeps the cells connected to each other.(25,26) In other words, turmeric helps brain cells stay healthy.
And now the UCLA Alzheimer's Disease Research Center (ADRC) is using turmeric in clinical trials and studying the effect of this powerful spice in patients diagnosed with this devastating disease. Clinical trials are the gold standard of medical research. But it's rare in Alzheimer's disease. And it's even more rare when all-natural herbs and spices like turmeric are used in hopes that positive benefits will be discovered. The head of UCLA's research team was recently interviewed and stated that setting out to hopefully prove turmeric's ability to prevent and treat Alzheimer's disease was “tremendously exciting.”(27)
- I recently read that one of the nonsteroidal anti-inflammatory drugs (NSAID) was found to prevent Alzheimer's disease. Is this true?
Scientists recently studied ibuprofen, one of the NSAIDs investigated for Alzheimer's Disease Prevention.(28) Ibuprofen belongs to a family of drugs that includes naproxen, indomethacin, nabumetone, and several others. These drugs are used most often to get rid of headaches, mild arthritis, and other kinds of pain and inflammation.(29) In the studies, the average dose of ibuprofen was 800mg a day. Patients took the product for two years. While the results suggested that ibuprofen might reduce the risk of developing Alzheimer's, ibuprofen's side effects are too harmful to be a valid lifelong prevention aid treatment.(28) Ibuprofen, like other NSAIDs, can cause gastrointestinal bleeding when used at high dosages over a long period of time. Long term use of ibuprofen can also lead to analgesic nephropathy, a kind of kidney damage caused by NSAIDs.(29)
As we discussed earlier, turmeric appears to block and break up brain plaques that cause the disease and helps reverse some of the damage already present.(19,21,26) Ibuprofen does not provide any protection against free radical damage. No anti-inflammatory medicine can do this.(29)
- If I eat curry will I be protected against Alzheimer's disease? There aren't many foods or recipes I make that require curry, do I need to eat it every day? And how much do I need?
If you enjoy Indian cuisine, by all means, enjoy these delicious foods. You'll benefit your brain and your appetite. But you make a good point, American meals rarely contain curry. That's why supplements that contain extracts are suddenly quite popular. In fact, there are numerous turmeric/curcumin supplements on the market today.
But like all nutritional supplements, some turmeric supplements are superior to others. You need to read their labels to make sure the turmeric extract you are buying will provide the protection you need. Look for high-potency turmeric extract from turmeric (Curcuma longa) rhizome. And make sure the extract is standardized to contain 90% curcuminoids, the active ingredient in turmeric responsible for the positive research findings.
Researchers once thought that preventing for Alzheimer's disease would elude them for decades. In fact, several scientists privately speculated the disease might never be ameliorated. They thought the origin of the disease was too complex and the symptoms of the disease were too profound. That's why the ongoing research on turmeric is so exciting. A safe, natural, and effective way to protect against Alzheimer's disease almost seems too good to be true. But, the nation of India and its low incidence of Alzheimer's disease are proof these are not just fluke findings - making turmeric extract a supplement to remember.
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