In the study, the famed Dr. Dean Ornish (who is best known for a 1990 study that used a similar intervention to reduce heart attack risk) at the University of California San Francisco took patients with early-stage dementia and divided them into a control group (who didn’t do anything in particular) and a study group who received an intensive lifestyle intervention that consisted of:
A low-fat vegan diet
Regular meditation and yoga for stress reduction
Daily “cardio” type exercise
Prioritizing good quality sleep
The results after 40 weeks were that the people in the control group got worse (as expected), whereas in the people receiving the intervention, 46% improved and 37% stabilized on a series of cognitive tests. Put another way, 83% of people doing the lifestyle program did a lot better than the people not doing the lifestyle program.
As with any study, there are some limitations to this one. But before I get into those let me just highlight a few things about this study that I think are really great:
This study adds to a few other studies that show lifestyle changes can be helpful for slowing cognitive decline. The fact that this finding seems to be repeatable across several studies strongly suggests that there really is something to it.
Intuitively, it makes sense that improved diet, exercise, sleep, and stress reduction would be beneficial for the brain, since there is robust evidence for all of those interventions in many other chronic conditions. As a general rule, when a study’s results make sense, they are much more believable.
We don’t have a lot of good treatment options for dementia, so even though this intervention is not a panacea (more on that momentarily), finding anything that might be helpful is a wonderful bit of news.
Finally, there are really no downsides to adopting a healthier lifestyle. If a person were to eat healthier, exercise more, and manage their stress better, the only “side effects” might be things like losing some weight, reducing risk for heart disease and diabetes, and so forth. If you have early stage cognitive issues and try the intervention in the study the “worst case scenario” is that your memory will not be helped but you will in other ways become healthier.
On a further point, this study took people who ALREADY had evidence of early-stage Alzheimer’s and showed improvements. While we can’t say for certain, it’s very likely that a similar intervention would be even more powerful for PREVENTING dementia from happening in the first place, since diseases are almost always easier to prevent than to cure. In other words, a healthy person in their 20s, 30s, or 40s who started implementing the methods in this study would probably reduce their risk for developing dementia later in life.
So in all, I think this study offers a real ray of hope. With that said, it’s way too soon to gloat about the results, so let’s discuss the limitations:
This was a relatively small study with only 26 participants. Small studies are always less trustworthy than large ones for the same reason that if you flip a dime 5 times and it always lands on heads, that probably is just a coincidence, whereas if you flip it 5,000 times and it always lands on heads, you can be pretty confident that you are holding a loaded coin. In real life, weird things happen all the time, and some patients with a diagnosis of dementia don’t progress very rapidly. It’s only when they happen a lot that you can be sure you didn’t just happen to stumble upon a group of people who had a slow moving form of dementia. Ergo, I would love to see this study repeated with at least a few hundred participants, rather than just 26.
17% of the participants did get worse, despite the intervention, and 37% only achieved stabilization, so in the best-case scenario, this is still not a cure-all. Less than half of patients actually improved.
The study was 40 weeks long. It’s great that a substantial number of the participants did better during those 40 weeks, but what will happen to them over the coming year? Two years? 10 years? We don’t know yet. But there’s a good chance that it won’t be anything good. Data showing that the effects could be experienced over a prolonged period of time would be really reassuring.
The folks in the study put in a LOT of time doing exercise and stress reduction work. How many people who are not enrolled in a structured program and who face the real life challenges of work, family commitments, and so forth would be able to sustain such efforts?
On the topic of effort, a notable trend in the study was that the subjects who participated most actively in the program had the best results. One way to look at that is a positive one: the program works so well that, the more it is used, the better the outcome. But another way to view this finding is a more skeptical one, and that is to assume that the people who were least impacted by their illness and had the least severe form of the disease were most able to participate, since apathy and difficulty staying on task are common symptoms of early dementia. Ergo, did the lifestyle intervention help people’s memory, or in a weird way did it select out the people who were already going to do better?
Finally, as with Dr. Ornish’s famous heart study, the participants got a full-court press of interventions. Therefore, it is impossible to tease out which parts of the intervention had the most benefit. Was it the mediation? Yoga? Daily cardiovascular exercise? The vegan diet? Better sleep? We wouldn’t be able to know unless the study was repeated with each of these interventions in isolation.
In sum: I think this study offers some real (and rarely found) hope in the world of dementia, and since there are very few downsides to trying the intervention that Dr. Ornish has devised, it might be worth adopting at least some of these lifestyle habits if you have, or are worried about eventually having, dementia.
But we really need much more research before stating that this particular intervention – or any lifestyle intervention for that matter – can dramatically impact Alzheimer’s outcomes.
