Can Alzheimer’s Disease Be Reversed with a Plant-Based Diet?

5/5 - (146 votes)

Dr. Dean Ornish publishes the first randomized controlled trial investigating whether a plant-based diet and lifestyle program may reverse the course of early-stage Alzheimer’s disease.

Discuss
Republish

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Dr. Dean Ornish was the first to show, in a randomized controlled trial, that a plant-based diet and lifestyle program could apparently reverse the progression of our number one killer, heart disease––opening up arteries without drugs, and without surgery.

Then, he showed the same plant-based program could potentially reverse the course of early-stage prostate cancer and elongate our telomeres, suggesting an anti-aging effect as well.  But when he told me he was going to try to reverse Alzheimer’s disease, I was skeptical. Surely, he was biting off a little more than he could chew.

Dementia is the most feared condition of later life. There’s a common misconception that we have no control over whether we develop dementia, but there is good news: although Alzheimer’s may be incurable, it is at least preventable.

There is an emerging consensus that “what’s good for our hearts is also good for our heads,” because clogging of the arteries inside the brain with atherosclerotic plaque is thought to play a role in the development of Alzheimer’s dementia. This is what our cerebral arteries should look like: open, clean, and allowing blood to flow throughout our brain. This is what atherosclerosis in our head looks like: clogged with cholesterol, closing off our arteries, and clamping down on blood flow. What kind of brain arteries do you want in your head?

Too much cholesterol in our blood is unanimously recognized to be a risk factor for the development of Alzheimer’s disease.  Those with a total cholesterol of 225 or more may have nearly 25 times the odds of ending up with amyloid plaques in their brain 10 to 15 years later. After all, what is the Alzheimer’s gene, APOE? It codes for the major cholesterol carrier inside the brain.

This may explain the so-called Nigerian paradox: they have among the highest rates of the Alzheimer’s gene, but some of the lowest rates of Alzheimer’s disease. How is that possible? Genes load the gun, but lifestyle pulls the trigger. The paradox may be explained by their low cholesterol levels, probably due to their diets low in animal fat.

So, in terms of dietary guidelines for the prevention of Alzheimer’s, we should center our diets around vegetables, legumes, fruits, and whole grains. In other words, the dietary pillar of lifestyle medicine: whole food, plant-based nutrition. Or, if that’s too complicated, plants, plants, and more plants. That may help explain why vegetarians may be up to three times less likely to become demented later in life. But it’s not all-or-nothing. Even just substituting five percent of animal protein with plant protein appears to significantly reduce the risk of dying from dementia.

But prevention isn’t sexy. When prevention works, nothing happens. But the same diet and lifestyle that help prevent heart disease were proven to help reverse it. Until then, it was believed that heart disease progression could only be slowed, not stopped or reversed––which is similar to how Alzheimer’s disease is viewed today. So, what if you put people with Alzheimer’s on the same plant-based program? You don’t know until you put it to the test.

Dr. Ornish and his team conducted a randomized, controlled, phase 2 clinical trial to see if the progression of Alzheimer’s disease may be slowed, stopped, or perhaps even reversed. They randomized about 50 men and women diagnosed with early-stage Alzheimer’s to either make no lifestyle changes for 20 weeks, or eat a whole food, plant-based diet (with supplements like vitamin B12), exercise moderately (like walking half an hour a day), practicing stress management (like relaxing with breathing exercises), and getting group support (over Zoom).

The researchers measured standard tests of cognition and function before and after in each group, as well as objective experimental biomarkers of disease progression. On the Clinical Dementia Rating Global scale, which is used to stage the severity of dementia, the control group continued to get worse, but the diet and lifestyle group started to get better. People diagnosed with Alzheimer’s getting better? The same seemed to happen when measured with the Alzheimer’s Disease Assessment Scale, though that did not reach statistical significance. Using what’s called the Clinical Dementia Rating Sum of Boxes scoring, both groups continued to decline, but the decline was significantly less in the healthy living group. Overall, using what’s called the Clinical Global Impression of Change scoring, most of the people in the control group kept getting worse, and none showed any improvement, whereas about 40 percent of those in the diet and lifestyle group appeared to be getting better within five months of eating and living more healthfully. Why did some get better and others not? Well, the more the study participants complied with the recommendations, the greater the beneficial impact on their cognition and function. This helps to explain why studies of less-intensive lifestyle interventions were not sufficient to stop disease progression, let alone actually improve cognition and function.

The biggest limitation of the study is that, unlike drug trials where you can give people a disguised placebo sugar pill, when a study involves major diet and lifestyle changes, you can’t rule out the placebo effect, especially for self-reported, subjective questions like “How’s your memory been?” But the researchers also measured objective investigational biomarkers of disease progression and saw the same kind of trajectory—improvements in the interventional group and worsening in the control group, with the same apparent dose-response effect, meaning the more they improved their diet and lifestyle, the more dramatic the effect.

Compare that to the latest Alzheimer’s drugs, which may even not work at all.  All you may get for your $56,000  is a one-in-three chance of swelling or bleeding in your brain. When the U.S. Food and Drug Administration approved the drug anyway, the head of the American Geriatrics Society replied, “My head just exploded.”

The bottom line is there is only one diet that has been shown to help reverse our leading cause of death, heart disease, in the majority of patients: a plant-based diet. If that’s all a plant-based diet could do—reverse the number one killer of men and women, then shouldn’t that be the default diet until proven otherwise? And the fact that it can also be effective in preventing, arresting, and reversing the progression of other leading killers, like high blood pressure, type 2 diabetes, and now maybe even early-stage Alzheimer’s disease, would seem to make the case for plant-based eating simply overwhelming.

Please consider volunteering to help out on the site.

Motion graphics by Avo Media

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Dr. Dean Ornish was the first to show, in a randomized controlled trial, that a plant-based diet and lifestyle program could apparently reverse the progression of our number one killer, heart disease––opening up arteries without drugs, and without surgery.

Then, he showed the same plant-based program could potentially reverse the course of early-stage prostate cancer and elongate our telomeres, suggesting an anti-aging effect as well.  But when he told me he was going to try to reverse Alzheimer’s disease, I was skeptical. Surely, he was biting off a little more than he could chew.

Dementia is the most feared condition of later life. There’s a common misconception that we have no control over whether we develop dementia, but there is good news: although Alzheimer’s may be incurable, it is at least preventable.

There is an emerging consensus that “what’s good for our hearts is also good for our heads,” because clogging of the arteries inside the brain with atherosclerotic plaque is thought to play a role in the development of Alzheimer’s dementia. This is what our cerebral arteries should look like: open, clean, and allowing blood to flow throughout our brain. This is what atherosclerosis in our head looks like: clogged with cholesterol, closing off our arteries, and clamping down on blood flow. What kind of brain arteries do you want in your head?

Too much cholesterol in our blood is unanimously recognized to be a risk factor for the development of Alzheimer’s disease.  Those with a total cholesterol of 225 or more may have nearly 25 times the odds of ending up with amyloid plaques in their brain 10 to 15 years later. After all, what is the Alzheimer’s gene, APOE? It codes for the major cholesterol carrier inside the brain.

This may explain the so-called Nigerian paradox: they have among the highest rates of the Alzheimer’s gene, but some of the lowest rates of Alzheimer’s disease. How is that possible? Genes load the gun, but lifestyle pulls the trigger. The paradox may be explained by their low cholesterol levels, probably due to their diets low in animal fat.

So, in terms of dietary guidelines for the prevention of Alzheimer’s, we should center our diets around vegetables, legumes, fruits, and whole grains. In other words, the dietary pillar of lifestyle medicine: whole food, plant-based nutrition. Or, if that’s too complicated, plants, plants, and more plants. That may help explain why vegetarians may be up to three times less likely to become demented later in life. But it’s not all-or-nothing. Even just substituting five percent of animal protein with plant protein appears to significantly reduce the risk of dying from dementia.

But prevention isn’t sexy. When prevention works, nothing happens. But the same diet and lifestyle that help prevent heart disease were proven to help reverse it. Until then, it was believed that heart disease progression could only be slowed, not stopped or reversed––which is similar to how Alzheimer’s disease is viewed today. So, what if you put people with Alzheimer’s on the same plant-based program? You don’t know until you put it to the test.

Dr. Ornish and his team conducted a randomized, controlled, phase 2 clinical trial to see if the progression of Alzheimer’s disease may be slowed, stopped, or perhaps even reversed. They randomized about 50 men and women diagnosed with early-stage Alzheimer’s to either make no lifestyle changes for 20 weeks, or eat a whole food, plant-based diet (with supplements like vitamin B12), exercise moderately (like walking half an hour a day), practicing stress management (like relaxing with breathing exercises), and getting group support (over Zoom).

The researchers measured standard tests of cognition and function before and after in each group, as well as objective experimental biomarkers of disease progression. On the Clinical Dementia Rating Global scale, which is used to stage the severity of dementia, the control group continued to get worse, but the diet and lifestyle group started to get better. People diagnosed with Alzheimer’s getting better? The same seemed to happen when measured with the Alzheimer’s Disease Assessment Scale, though that did not reach statistical significance. Using what’s called the Clinical Dementia Rating Sum of Boxes scoring, both groups continued to decline, but the decline was significantly less in the healthy living group. Overall, using what’s called the Clinical Global Impression of Change scoring, most of the people in the control group kept getting worse, and none showed any improvement, whereas about 40 percent of those in the diet and lifestyle group appeared to be getting better within five months of eating and living more healthfully. Why did some get better and others not? Well, the more the study participants complied with the recommendations, the greater the beneficial impact on their cognition and function. This helps to explain why studies of less-intensive lifestyle interventions were not sufficient to stop disease progression, let alone actually improve cognition and function.

The biggest limitation of the study is that, unlike drug trials where you can give people a disguised placebo sugar pill, when a study involves major diet and lifestyle changes, you can’t rule out the placebo effect, especially for self-reported, subjective questions like “How’s your memory been?” But the researchers also measured objective investigational biomarkers of disease progression and saw the same kind of trajectory—improvements in the interventional group and worsening in the control group, with the same apparent dose-response effect, meaning the more they improved their diet and lifestyle, the more dramatic the effect.

Compare that to the latest Alzheimer’s drugs, which may even not work at all.  All you may get for your $56,000  is a one-in-three chance of swelling or bleeding in your brain. When the U.S. Food and Drug Administration approved the drug anyway, the head of the American Geriatrics Society replied, “My head just exploded.”

The bottom line is there is only one diet that has been shown to help reverse our leading cause of death, heart disease, in the majority of patients: a plant-based diet. If that’s all a plant-based diet could do—reverse the number one killer of men and women, then shouldn’t that be the default diet until proven otherwise? And the fact that it can also be effective in preventing, arresting, and reversing the progression of other leading killers, like high blood pressure, type 2 diabetes, and now maybe even early-stage Alzheimer’s disease, would seem to make the case for plant-based eating simply overwhelming.

Please consider volunteering to help out on the site.

Motion graphics by Avo Media

Doctor's Note

What does improving the cognition and function of Alzheimer’s patients with lifestyle medicine actually translate to in terms of human impact? Check out the video.

For more on Alzheimer’s disease, see these videos:

For more on Dr. Dean Ornish’s work, check out these videos; for more on heart disease, see these videos

I have more than 500 videos on plant-based diets. You can check them out here

The best available balance of scientific evidence suggests that the healthiest way to eat is a vitamin B12-fortified diet centered around whole plant foods. I go into specifics of the Daily Dozen foods I recommend in Dr. Greger’s Daily Dozen. For a more thorough dive into the science on these foods, check out my New York Times bestselling book, How Not to Die.

Join our Plant-Based Living Series. This resource is a weekly email series that gives you simplified takeaways and actionable tips on healthy eating. Whether you’re new to a whole food, plant-based lifestyle or would benefit from reminders on some of the key aspects of healthy evidence-based nutrition, this series is for you. Expanding on our popular Evidence-Based Eating Guide, this free series features even more tips and information, and you’ll get it delivered straight to your inbox on a weekly basis. (Don’t have your own copy of our Evidence-Based Eating Guide? You can download it as a digital and printable PDF.)

If you haven’t yet, you can subscribe to my videos for free by clicking here. Read our important information about translations here.

Subscribe to our free newsletter and receive our Daily Dozen Meal Planning Guide.

Pin It on Pinterest

Share This