High-Fat Diet Linked to Alzheimer's

A high-fat diet may play a role in the development of Alzheimer's disease, a new animal study suggests. A diet rich in animal fat and low in omega-3 fatty acids reportedly increased brain markers linked to Alzheimer's disease.

The researchers genetically altered mice to produce two proteins that are found in the brains of Alzheimer's patients: tau proteins and amyloid-beta proteins. Tau proteins prevent nerve cells (called neurons) from functioning properly, while amyloid-beta proteins have been linked to the formation of abnormal deposits in the brain called senile plaques. The mice received either a regular diet or a high-fat diet low in omega-3 fatty acids for nine months.

The mice that ate high-fat diets had 1.5 times more tau protein and 8.7 times more amyloid-beta protein than mice in the control group. The high-fat diet also decreased levels of drebrin protein in the brain, which is another sign of Alzheimer's disease.

"Our findings lead us to believe that a diet containing more omega-3s and less saturated fat could prevent the development of Alzheimer's, at the very least among people genetically predisposed to the disease," said lead author Dr. Frédéric Calon. "We cannot state with any certainty that what we have observed among transgenic mice also occurs in humans, but there is no harm in eating less fat and more omega-3s," he added.

Some of the most recent research indicates that taking steps to improve heart health, such as losing weight, exercising and controlling high blood pressure and high cholesterol, may also help prevent Alzheimer's disease.

In addition, strong evidence suggests that ginkgo may be beneficial in people with early-stage Alzheimer's disease. In fact, some research has shown that it may be as effective as acetylcholinesterase inhibitor drugs such as donepezil (Aricept®).

For more information about integrative therapies for Alzheimer’s disease, please visit Natural Standard's Comparative Effectiveness database.

Comments

[Paul]

Are these genetic makers -- tau proteins and amyloid-beta proteins -- being tracked in living mice or is it by autopsy? If it can be done in mice, could it be done in humans? If not, would it be possible to do a study via autopsy in humans with Alzheimer's disease who had various eating habits? What about people who already eat a low-fat diet, high in omega-3, is there a lower prevalence of Alzheimer's disease among them?

[Sophia]

It is proven that a healthier diet, low in saturated fats and high in omega fatty acids, has beneficial effects on the heart. I would expect it to also improve overall health. Seeing data, though in mice, that a healthier diet may decrease the chances (and proteins involved) in Alzheimer’s confirms that as a society, we need to move forward and press for healthier lifestyles.

[trish]

This study is another proven fact to the benefit of omega-3 and the health risks of saturated fats, including the link to Alzheimer’s.

[susan allport]

Thought you would be interested in this short omega-3 video: http://www.youtube.com/watch?v=eIgNpsbvcVM

[Elizabeth Smith]

I have to say, this article does not surprise me. High-Fat diets are linked to so many health problems that this is just another one to add to the list. I didn’t realize that ginkgo could possibly help Alzheimer’s.

I think Americans as a whole have to start watching what they eat. Fats are essential in our diets, but what types of fats, and how much is what we have to learn more about.

If a person with Alzheimer’s started eating a low-fat diet and incorporating ginkgo, would their memory improve, or is the damage already done? That would be interesting to test on the rats.

[Timothy]

Tau proteins and amyloid-beta proteins can be tested by a sample of the cerebral spinal fluid (CSF). This study could be done in humans, but it may be difficult to enroll Alzheimer's patients who are willing to receive a spinal tap periodically for testing. If the study was not done to confirm the relationship of these proteins and low-fat, high-omega-3 diets, patients could still adopt that eating habit because it would not hurt them and may bring them some possible benefits.

[Becca]

Interesting studies in mice show that a diet rich in animal fat and poor in omega-3 fat increase tau proteins, amyloid beta and drebin protein concentrations, which are coupled with Alzheimer’s disease-like neuropathology. Diets high in animal fat could affect the inflammatory response of the brain.

[S. Shah]

I agree with Elizabeth, and I'm not surprised that an unhealthy diet full of fatty foods would cause the plaques and dysfunctional neurons seen in Alzheimer’s. People may find it surprising that the content of their foods can cause such direct effects on the brain, but what we eat is carried all throughout our bodies and affects all aspects of how we function. This article reinforced this idea for me, and I hope people begin to understand the crucial importance of a healthy diet.

[Evan]

I think society is definitely more conscious about what foods are healthy and at the very least, know that fatty foods are not good for one’s cardiovascular health. It’s not that the public doesn’t know this, it’s because the public continues to eat unhealthily despite the fact. These data about high-fat and Alzheimer’s confirms what is generally understood about saturated fats. It’s great that there’s more and newer information about the relationship of high-fat diets and morbid conditions. More importantly, the push should be lifestyle modifications!

[liz]

A high-fat diet has been linked to many health issues, while a diet low in fat and high in omega-3s is good for overall health

[Betty Johnson]

Interesting on the fats...following this same chain of thought, I wonder what effects medications that are highly fat soluble would have on the causation of Alzheimer's. For example, some of the statin medications: Could the presence of a drug to treat cholesterol actually cause the formulation and accumulation of these proteins? How about patients or the general public who are exposed to THC? There is some evidence that cognition is negatively affected, but could this also involve expediting the onset of Alzheimer's in some patients? More data are needed.

[Metu]

An interesting, VERY preliminary study. Just because a diet low in omega-3s (and high in fat) increased plaques, it doesn't necessarily mean that a diet high in omega-3s would decrease plaque formation. It may be the simply the lack of dietary fat is sufficient alone (i.e., omega-3s may not have any effect). I wonder why they didn't have another group of mice that were fed a diet that was just high in omega-3s. It seems to be a rather obvious omission.

[lilian]

This is a really interesting study! There is still so much more to learn about Alzheimer’s disease, and it is great to see positive findings. Omega-3 fatty acids are associated with numerous health benefits and should be included in everyone’s daily diet.

[K.K.]

I agree with Dr. Calon that more omega-3s and less fat in our diets can keep us healthy longer. If someone could identify an enzyme that would break down the tau and amyloid-beta proteins we might have a treatment for Alzheimer’s disease.

[Lance B.]

It is really easy to talk about lifestyle changes, exercising and eating healthy, but actually doing it is difficult. Eating habits are called so because they are habits, and humans are creatures of habits, and habits are hard to break. To stop eating something that you have been eating for years and changing to something else would take a long time, it's not something that can be done just like that. Yes, low-fat diets high in omega-3 fatty acids are good for overall health and in preventing diseases like Alzheimer's, but more should be done to help Americans in the transition.

[SUMA]

According to a study done by Lichtenstein AH, Kennedy E, Barrier P, et al., “dietary guidelines have emerged over the past 30 years recommending that Americans limit their consumption of total fat and saturated fat as one way to reduce the risk of a range of chronic diseases. A low-fat diet is not a no-fat diet. Dietary fat clearly serves a number of essential functions. The association between dietary fat and CHD has been extensively studied. Diets high in saturated fatty acids and trans fatty acids increase LDL cholesterol levels, and in turn, the risk of heart disease. The majority of individuals--regardless of age--do not report consuming a diet that meets the levels of fat and saturated fatty acids recommended by the Dietary Guidelines for Americans. On a relative basis, saturated fat intake has gone down less than has total fat intake.”

According to the Alzheimer’s Association Web site, “Alzheimer’s is a progressive and fatal brain disease. As many as five million Americans are living with Alzheimer’s. Alzheimer’s destroys brain cells and causes problems with memory, thinking and behavior severe enough to affect work, social life or lifelong hobbies. Alzheimer’s gets worse over time, and it is fatal. Today, it is the sixth-leading cause of death in the United States. Anyone who has watched a love one suffer from this disease has to be moved by these statistics. The results of this study hold promise for those people genetically predisposed to the disease. I agree with the authors who state these results may not be applicable to humans, but there is no harm in eating less fat and more omega-3s. More studies need to be done to evaluate if these results can be applied to humans

[Marie]

Alzheimer’s disease affects one of the most intricate and complex human organs. There is still so much to learn about this devastating disease, and this study may provide some insight on its pathology. Omega-3 fatty acids have many health beneficial affects, and this study once again proves the importance of integrating omega-3s in our diets.

[Shaily]

Metu, I agree with you about how an increase omega-3s doesn't necessarily lead to less plaque formation. More research is definitely needed to narrow in on this causation, but at least this adds to the wealth of research that concludes that omega-3s are an important part of our diets.

[Anna H.]

The first segment describing the effects of high-fat diet on the increased levels to tau and amyloid beta proteins in rats is apt, but verification of a parallel response in humans is necessary, where Alzheimer's disease is more prevalent.

The second part of study states the significance of exercise. There is a relationship between a healthier heart and a healthier brain (i.e. reduced proneness to get the fatal disease).

[tony]

Eating high-fat diets, especially with saturated fats, has been shown to cause atherosclerosis and other complications. Omega-3 has been noted to improve memory and help with cardiac health. I think everyone should be cautious of high-fat diets and have more omega-3 for their general health.

[Adam]

I am not surprised by the findings of this study. However, I am surprised they did not included an omega-3 only group to compare to the other groups, this way the beneficial effect of omega-3 would be more obvious. Even though fat (in moderation) is necessary for neurological development, excessive amounts, especially of saturated fats, can be harmful. This study further validates the beneficial effects of omega-3. Not only has it been shown to be beneficial for heart health, but it has also been shown to help with memory and enhance thinking. So I am not surprised to learn that it can help people with Alzheimer.

[MHD]

Although I am familiar with the protective effects of omega-3 against cancer and lowering triglyceride levels, this is the first time I have encountered a study that has reported a decrease in Alzheimer's risks. A similar study was published in 2005 that correlated a decrease in Alzheimer's risks with the Mediterranean diet, which involves consuming mostly fish, vegetables, olive oil and whole grains. Fish is one of the most abundant sources of omega-3 fat. It could be that there is a link between these two studies. Perhaps eating fish, and essentially omega-3 fats, can lead to a decreased risk in Alzheimer's.